the relationship between board gender diversity and firm ... · the upper echelons theory (uet) is...
TRANSCRIPT
The Relationship between Board Gender Diversity and Firm Performance: A
Comprehensive Evaluation
J.D Jayaraman, Ph.D.
Associate Professor
Department of Finance
New Jersey City University
Prathibha Amand.
Verisk Analytics, Inc.
Address for correspondence:
J.D Jayaraman, Ph.D.
Department of Finance
School of Business
New Jersey City University
Harborside 2, Jersey City, NJ 07311
Email: [email protected]
Phone: 917-514-4277
Prathibha Amand
Verisk Analytics, Inc.
545 Washington Blvd, Jersey City, NJ 07310
2
The Relationship between Board Gender Diversity and Firm Performance: A
Comprehensive Evaluation
Abstract
In the recent past board gender diversity has garnered significant academic and media interest.
Whether increasing gender diversity on boards leads to better firm financial performance is still
an open question. We investigated the relationship between board gender diversity (BGD) and
firm performance (FP) using a large sample of the firms in the Russell 3000, S&P Europe 350,
and S&P Asia 50 indices, over the most recent 11 years (2008 – 2018). To identify the effect of
BGD on firm performance we used a dynamic panel model that accounts for the endogeneity
biases that are inherent in the BGD-FP relationship. We do not find evidence of any relationship
between BGD-FP. We also investigated the existence of a critical mass of 30% women directors
beyond which firm performance begins to improve, suggesting a “U” shaped relationship
between BGD and FP. We found no evidence of a critical mass nor a “U” shaped relationship.
Our results were robust and held up under extensive robustness checks.
Keywords: Board gender diversity, corporate governance, women on board, critical mass
3
Introduction
The composition of a company’s board of directors has long been an important area of
corporate governance research. Corporate boards make important decisions that impact the lives
of not only the company’s employees, but also the community, country and the global market.
In the recent past there has been increased focus on gender diversity in corporate boards and a
move towards increasing the proportion of women on corporate boards. Many countries (e.g.
Norway, Spain, Belgium, and India) have imposed quotas for women on the board. In this
current environment of heightened interest in board gender diversification, whether gender
diversity on boards impacts firm performance becomes an important research question.
Although there is a fairly large body of literature on board gender diversity (BGD) and
firm performance (FP), the debate on whether higher board gender diversity leads to better firm
performance is anything but settled. Empirical evidence for the relationship between BGD and
FP is inconsistent and inconclusive. One set of studies suggest that women directors add value
and have a positive impact on the firm’s financial performance (Nguyen & Faff, 2012; Singh,
Vinnicombe, & Johnson, 2001; Erhardt, Werbel, & Shrader, 2003, Campbell & Mínguez-Vera,
2008; Carter, Simkins, & Simpson, 2003; Francoeur, Labelle, & Sinclair-Desgagné, 2008) while
another stream of literature finds exactly the opposite - a negative relationship between BGD and
FP (Darmadi, 2011; Minguez-Vera & Martin, 2011; Bøhren & Strøm, 2010; Adams & Ferreira,
2009; Haslam, Ryan, Kulich, Trojanowski, & Atkins, 2010). A third stream of literature finds no
relationship between BGD and FP (Carter, D'Souza, Simkins, & Simpson, 2010; Rose, 2007;
Shrader, Blackburn, & Iles, 1997). Thus, the impact of board gender diversity on firm
performance is still an open question that warrants further research.
4
The other question that has been less extensively explored in the literature is whether
there is a critical mass of women directors beyond which there is a positive impact of BGD on
FP. The argument is that there is a threshold number of women directors that needs to be
reached to move from tokenism, break gender barriers and reap the benefits of gender diversity.
The current empirical evidence seems to suggest that there is a critical mass of women directors
somewhere around 30% (Wiley & Monllor-Tormos, 2018; Cohen, Broschak, & Haveman, 1998;
Joecks et al., 2013; Kramer et al., 2006). But, these studies use small restricted samples over
short and older time periods (e.g. Joecks et al, 2013 uses a sample of 151 firms in Germany from
2000 to 2005) and most do not account for endogeneity issues that peril empirical investigations
of such relationships. Thus, the existence of a critical mass of women directors is still an open
question and warrants further investigation.
Our study contributes to the BGD – FP relationship literature by investigating the
relationship between board gender diversity and firm performance using a large sample of all the
firms in the Russell 3000 for a period of 11 years (2008 – 2018). The Russell 3000 represents
about 98% of all U.S. incorporated stocks. We also investigate the BGD – FP relationship in
non-U.S. companies using firms in the S&P Europe 350, and S&P Asia 50 indices. We
contribute to the critical mass literature by investigating the existence of a critical mass of
women directors in the large sample described above. We employ a robust statistical
methodology (Dynamic Panel System Generalized Method of Moments) that takes into account
endogeneity biases that makes results questionable if not accounted for (a majority of the extant
literature on BGD and FP is plagued by endogeneity issues). To the best of our knowledge ours
is one of the largest and most comprehensive sample in which BGD – FP relationship and the
5
existence of a critical mass has been investigated using a robust statistical methodology that
accounts for endogeneity issues.
The rest of the paper is organized as follows: We present an overview of the literature
which is followed by the development of the research questions and hypotheses. We then
describe the sample and methodology. Next we present the results and discuss them. Finally we
conclude by discussing some limitations and suggestions for further research.
Literature Review
Empirical evidence of the relationship between board gender diversity and firm financial
performance is ambiguous and inconclusive. All three possibilities – positive, negative, none –
have been found in the literature. We present a brief overview of the key theories that have been
put forth to explain the BGD-FP relationship and then discuss the three strands of literature on
the relationship between BGD and FP.
Board Gender Diversity Theories
The Agency Theory asserts that the separation of ownership and control creates agency
costs due to managers acting in their own interest rather than in the interest of the shareholders.
Boards are one way to mitigate this agency cost. Based on agency theory, researchers have
proposed that greater diversity in the board will lead to greater monitoring of managers and thus
improve firm performance (Carter et al. (2003); Hillman & Dalziel, 2003; Pfeffer & Salancik,
1978). Thus the agency theory suggests a positive relationship between BGD and FP with
increased gender diversity in boards leading to better firm performance. There is some empirical
support for the positive effect of women on the monitoring responsibilities of the board. Women
directors and culturally diverse board members could put forth unique questions (Campbell &
6
Mínguez-Vera, 2008) and introduce new perspectives (Rosener, 1990) that can add value to the
decision making process and increase board independence (Carter et al., 2003).
The Resource Dependence Theory (RDT) is another theory that has been used to explain
the BGD-FP relationship. The crux of this theory is that companies must effectively manage
uncertainity in their environement for them to be successful. Board members help the company
in obtaining resources that may not be otherwise available, through their contacts and
networking. Women on boards help with access to a broader range of stakeholders (Siciliano,
1996). Women board directors increase the legitimacy of an organization (Hillman & Dalziel,
2003) and increase information exchange (Larcker, So, & Wang, 2013), which, in turn, enhances
customer and employee relations (Hillman, Shropshire, & Cannella, 2007) and ultimatley leads
to increased firm performance. Thus, RDT also suggests a positive relationship between BGD
and FP.
The Upper Echelons Theory (UET) is yet another theory that focuses on upper
management and has been used to explain the relationship between BGD and FP. According to
UET, directors have different cognitive frames, and these cognitive frames (information-seeking
and evaluation processes) impact firm performance (Hambrick, 2007). Observable
characteristics of directors such as their race or gender have been used as proxies for cognitive
frames (Dezsö & Ross, 2012; Krishnan & Park, 2005). Female directors are likely to bring
different cognitive frames to a board due to differences in experiences and knowledge. For
example, female directors tend to have more university degrees and are more likely to hold
advanced degrees than male directors (Carter et al., 2010; Hillman, Cannella, & Paetzold, 2000;
Hillman, Cannella, & Harris, 2002) and are stronger in marketing and sales (Groysberg & Bell,
2013). Women board directors are less likely to have been CEOs or COOs and predominantly
7
come from non-business backgrounds (Hillman et al., 2002; Singh et al., 2008). Female
directors are likely to have new and different understandings of consumer markets (Bilimoria &
Wheeler, 2000; Campbell & Minguez-Vera, 2008; Carter, Simkins, & Simpson, 2003) and thus
can enrich the board. Thus, the UET posits a positive relationship between BGD and FP.
There are several theories that suggest a negative relationship between BGD and FP.
Social Identity Theory (Tajfel, 1978; Ashforth & Mael, 1989) suggests that people maintain a
positive identity by associating themselves with similar people, and this can lead to in-group vs
out-of-group friction. Another theory called the Similarity Attraction Theory (Byrne, 1971)
posits that birds of a feather flock together and thus tensions can arise between groups. Yet
another theory called the Self-Categorization Theory (Turner et al., 1987) suggests that people
create social categories based on external characteristics like gender, which leads to inter group
conflicts. The negative group dynamics described by these theories hinders communication
between male and female directors and generates distrust (Jehn, Northcraft, & Neale, 1999;
Milliken & Martins, 1996). Thus, these theories suggest that firm performance will be
negatively impacted with more women on the board.
The Critical Mass Theory (CMT) tries to reconile between the poitive and negative
theories and suggests that a critical mass of women directors are needed before there is a positive
impact on firm performance. For example Konrad et al. (2008) posit that with three or more
women on the board, the focus changes from gender to talent, thus reducing any bias they may
feel (Torchia et al., 2011). Female directors could be perceived as “tokens” and not trusted or
respected when there are only a few of them (Torchia et al., 2011). Thus, the CMT implies a
“U” shaped relationship between BGD and FP.
8
Having summarized the popular theories explaining the BGD-FP relationship, we
proceed to provide an overview of the literature that has found empirical evidence of a positive,
negative or no realtionship between BGD-FP.
Empirical evidence
There have been a plethora of studies that have examined the empirical evidence for the
relationship between BGD and FP. Burke (1997), was one of the first researchers who found
that companies with women on their board had a significant competitive advantage, which
resulted in higher sales. Singh & Vinnicombe (2004) analyzed UK companies and found that
companies with greater BGD had better governance and higher market capitalization. De Luis
Carnicer et al. (2008) found a positive relationship between BGD and accounting returns using a
sample of 2,000 Spanish companies.
Other studies have found a positive relationship between BGD and improved profitability
(Erhardt, Werbel, & Shrader, 2003), higher firm value (Campbell & Mínguez-Vera, 2008;
Carter, Simkins, & Simpson, 2003), and higher abnormal returns (Francoeur, Labelle, &
Sinclair-Desgagné, 2008).
On the other hand there have been several studies that have found a negative relationship
between BGD and FP. Adams and Ferreira (2009) found a negative relationship between BGD
and FP (as measured by Tobin’s Q and ROA) in a sample of U.S.. firms from 1996 to 2003.
Similarly, Haslam, Ryan, Kulich, Trojanowski, and Atkins (2010), in a study of the FTSE 100
companies between 2001 to 2005, found that BGD had a negative influence on ROA and ROE.
Watson and Robinson (2003) found a negative relationship between BGD and FP and attributed
it to women being more risk averse.
9
Contrary to all the above findings many studies found no relationship between BGD and
FP. Carter et al. (2010) studied companies in the S&P 500 from 1998 to 2002 and found no
evedence of a relationship between BGD and FP. Rose (2007) analyzed Danish companies,
excluding banks and insurance companies found no relationship between BGD and Tobin’s Q.
Shrader, Blackburn, & Iles (1997) found that BGD is unrelated to ROI, ROE and ROA.
A succinct summary of the literature from the Oxford Handbook of Strategy
Implementation (Hitt et al., 2017) is shown in Table 1.
---------------------------------
Insert Table 1 about here
---------------------------------
There have been a couple of meta analysis conducted to investigate the relationship
between BGD and FP found in the extant literature. Post and Byron (2015) analyzed the
findings from 140 studies of board gender diversity with a combined sample of more than 90,000
firms from more than 30 countries and found weak evidence of a positive relationship between
BGD and accounting returns. The strength of the relationship was found to be close to zero.
Pletzer, Nikolova, Kedzior, and Voelpel (2015) conducted a meta analysis on 20 studies with
3057 companies and found no relationship between BGD and FP. Thus, the meta analysis
studies, which combine the conflicting findings in the literature to provide an overall effect,
conclude that the relationship between BGD and FP is very weak at best and close to zero.
Now we turn to the literature on the existence of a critical mass in the BGD-FP
relationship. Kramer, Konrad, Erkut, and Hooper (2006) carried out a qualitative study
by interviewing 50 women directors, 12 CEOs, and seven corporate secretaries from Fortune
1000 companies and found that a critical mass of three or more women could enhance corporate
governance. Strydom et al. (2016), in an analysis of Australian firms from 2005 to 2013,
10
suggested the existence of a U-shaped relationship between BGD and earnings and indicated
30% as the tipping point. Joecks et al. (2013) studied 151 German companies over 2000 to 2005
and found that boards with three or more women directors are associated with higher ROE.
Wiley & Monllor-Tormos (2018) found a “U” shaped relationship between number of female
directors and firm performance measured by Tobin’s Q, in a sample of Fortune 500 firms in the
science, technology and finance firms. They also found evidence of critical mass at 30%.
Research Questions and Hypotheses
Although Agency Theory, Resource Dependence Theory, Social Identity Theory,
Similarity Attraction Theory and Self-Categorization Theory have been used to explain the
relationship between BGD and FP, the Upper Echelons Theory (UET) provides a strong and
clear theoretical foundation for connecting board gender diversity and firm performance (Post &
Byron, 2015) and hence we use the UET as the theoretical framework for our hypothesis
development.
One of the research questions that this study attempts to answer is whether there is any
relationship between board gender diversity and firm performance. Based on the Upper
Echelons Theory we propose that women on boards of directors, due to their different cognitive
frames and differences in terms of knowledge, experience, and values, shape both the content
and process of board decision-making and board activities that have a positive impact on firm
financial performance. This leads to our first hypothesis:
Hypothesis 1: Board gender diversity is positively related to firm financial performance. More
specifically, the number of female board directors is positively related to market performance as
measured by Tobin’s Q and accounting returns as measured by ROA and ROE.
We investigate this hypothesis in three regions of the world – U.S., Europe and Asia.
11
The second research question that this study attempts to answer is whether there exists a
critical mass of female directors beyond which there is a positive effect of increased board
gender diversity on firm financial performance. We draw on the Critical Mass Theory (CMT) to
formulate our second hypothesis. CMT suggests that there is a quadratic “U” shaped
relationship between BGD and FP and the empirical evidence suggests that the critical mass is at
30% female directors. This leads us to our second hypothesis:
Hypothesis 2: There exists a quadratic “U” shaped relationship between BGD and FP, with a
critical mass at 30%. More specifically, there exists a quadratic relationship between the
number of female directors on a board and market performance as measured by Tobin’s Q and
accounting returns as measured by ROA and ROE and this relationship is moderated by a
critical mass of 30% female board directors.
Again, we test this hypothesis in three regions of the world – U.S., Europe, Asia.
Methodology
Data
Extant literature on the relationship between BGD and FP has used sample sizes
anywhere from 112 firms over one year (Erhardt et al.,2003) to 1939 firms over eight years
(Adams & Ferriera, 2009). Our study uses all the firms in the Russell 3000 index for the U.S.,
S&P Europe 350 for Europe, S&P Asia 50 for Asia. The choice of time period for the analysis is
important to the results of the study. Many studies in the extant literature use older time frames
that may not be all that relevant in the current environment. The 2008 financial crisis brought
into focus the predominantly male dominated boards of U.S. companies and sparked a debate on
whether greater gender diversity could have prevented certain masculine behavior that allegedly
contributed to the financial crisis (McDowell, 2011; Van Staveren, 2014). There is some
12
evidence that since 2008 the male dominated boardroom culture has begun to change and
become more inclusive, female directors are more likely to be accepted and boardroom gender
bias has decreased (Jonsdottir, Singh, Terjesen, & Vinnicombe, 2015; Ryan & Haslam, 2007;
Sun, Zhu, & Ye, 2015). Hence, we chose a time period of the most recent eleven years from
2008 to 2018 for our study. Corporate governance data and financial performance data were
obtained from 2008 to 2018 from Bloomberg. Thus, our study is one of the most comprehensive
in terms of sample size and most recent in terms of time frame.
Variables
Dependent variables
The dependent variable is firm performance. Firm financial performance can be
measured by accounting returns and market performance. Accounting returns refers to how well
a firm uses its assets and investments to generate returns while market performance refers to the
behavior of a security in the market and reflects the market participant’s perception of the
financial soundness and future growth potential of the company. In this study, following extant
literature, we use Tobin’s Q as a market based measure of frim performance (Adams & Ferreira,
2009; Carter et al., 2003; Carter et al., 2007; Carter et al., 2010; Nguyen et al., 2015). Tobin’s Q
which is defined as the ratio of the market value of the company’s assets to the replacement cost
or book value of the company’s assets is widely considered as the best measure of a firm’s
market value (Dobbin & Jung, 2011). We take the natural log of Tobin’s Q to mitigate the
effects of outliers (Nguyen et al. 2015). We use the accounting measures Return on Assets
(Dobbin & Jung, 2011; Farrell & Hersch, 2005; Shrader et al., 1997) and Return on Equity
(Miller & Triana, 2009; Zahra & Stanton, 1988) for robustness checks.
13
Independent variables
The primary independent variable in our study is board gender diversity. BGD can be
measured by the number of female directors or the proportion of female directors or sometimes
just the presence of female directors on the board. In our study we use the number of female
directors as the primary independent variable (Carter et al., 2010; Dobbin & Jung, 2011). We
also conduct robustness checks using the percentage of female directors as the independent
variable (Adams & Ferreira, 2009; Nguyen et al., 2015).
Control Variables
We used several variables to control for firm characteristics, board characteristics and
macroeconomic factors that could impact firm performance (the dependent variable). The first
set of variables were to control for firm characteristics. These included the number of
employees, number of females in the workforce, number of female executives, and industry type.
The second set of variables were governance variables that involve the characteristics of
the board and its members. These include CEO related variables - CEO pay, CEO duality
(whether or not the CEO is also the chair of the board) , percentage of shares owned by the CEO,
CEO tenure and CEO age (Bhagat & Bolton, 2008; Holm & Scholer, 2010; Singla, George, &
Veliyath, 2010); board related variables - board size, board age, board average tenure (Rose,
Munch- Madsen, & Funch, 2013; Sanders & Carpenter, 1998; Zahra, Priem, & Rasheed, 2007),
independent directorship (Carter et al., 2010), directors who sit on the audit committee (Alderfer,
1986; Carlsson & Karlsson, 1970; Masulis, Wang, & Xie, 2007; Vroom & Pahl, 1971).
Finally, the third set of variables were the macro economic measures - Economic Policy
Uncertainty (EPU) index, which measures policy related economic uncertainty (Baker, Bloom &
Davis, 2015) and the Aruoba-Diebold-Scotti Business Conditions Index, which tracks real
14
business conditions (Aruoba, Diebold & Scotti, 2009). A vast majority of the studies in the
literature do not control for macroeconomic factors that might impact firm performance.
Moderating Variables
Research has indicated that 30% is the critical mass required to unlock the positive
impact of BGD on FP (Joecks et al., 2013). Other research studies have used number of female
directors rather than proportion and indicated that 3 women on the board is required for critical
mass (Konrad et al., 2008; Post et al., 2011). We find the proportion of women on the board to
be more meaningful when it comes to critical mass and hence use a dummy variable that takes a
value of 1 if there are 30% or more women on the board, and 0 otherwise, as our primary
moderating variable. But, we also conduct robustness checks with the absolute number of three
women on the board for critical mass. We also try various other critical mass percentages (20%,
40%, 50%) and number of women on the board (4, 5, 6, 7).
Table 2 provides a list of all the variables used in the study and their definitions.
---------------------------------
Insert Table 2 about here
---------------------------------
Analysis
The relationship between BGD and FP is prone to endogeneity bias (Hermalin &
Weisbach, 2001). High performing companies may be more inclined to bring women on to the
board (Farrell & Hersch, 2005). Board characteristics are also not exogenous random variables
and are chosen endogenously by firms based on their operating environment (Adams & Ferreira,
2007; Coles et al., 2008; Harris & Raviv, 2008). Certain unobservable firm characteristics that
are omitted, referred to as Omitted Variable Bias (OVB), can impact the relationship between
BGD and FP. One such example is corporate attitude towards Corporate Social Responsibility
15
(CSR), which is unobservable and can impact BGD. It is practically impossible for an empirical
model to capture all possible variables that have an impact on BGD and FP. Moreover when
endogenous explanatory variables are used in the model there is the possibility of reverse
causality, where rather than BGD affecting FP, FP might affect BGD. Another issue in such
studies is that the endogeneity is dynamic, in that there may be intertemporal effects between
governance variables and firm performance.
One common technique used to address endogeneity is the use of instrument variables.
One could identify an instrument variable that explains BGD but is exogenous to firm
performance, but it is a challenge to identify such a variable. Number of female connections of
male directors is one such instrument variable that has been commonly used in the literature, but,
studies have shown that this instrument variable is truly not exogenous (Sila, Gonzalez &
Hagendorff, 2016).
Thus, studies investigating the relationship between BGD and FP should control for the
endogenous nature of the BGD-FP relationship in order to obtain reliable estimates (Adams &
Ferreira, 2009; Carter et al., 2010; Dezsö & Ross, 2012; Hermalin & Weisbach, 2001). But,
much of the extant literature does not address endogeneity bias. Studies such as Zahra & Stanton
(1988), Erhardt et al. (2003), Shrader et al. (1997), Farrell & Hersch (2005), and Desvaux,
Devillard- Hoellinger, & Baumgarten (2007) use univariate analysis and do not address any
aspect of endogeneity, while studies such as Adams & Ferreira (2009), Anderson, Reeb,
Upadhyay, & Zhao (2011), Carter et al. (2010), Carter et al. (2003), and Sabatier (2015) only
attempted to control for two endogeneity biases: omitted variable bias and reverse causality.
In our study we employ a Dynamic Panel System Generalized Method of Moments
(DPS-GMM) model proposed by Arellano & Bover (1995) and Blundell & Bond (1998) which
16
allows us to simultaneously address all the endogeneity issues that impact the BGD-FP
relationship. The DPS-GMM estimator addresses reverse causality by instrumenting the
endogenous explanatory variables through their lagged values (Blundell & Bond, 1998). It
controls for dynamic panel bias by adding lags of each dependent variable (Roodman, 2009;
Wintoki et al., 2012). It mitigates omitted variable bias through a fixed effects approach
(Nguyen et al., 2015). Also, the GMM estimator has proven to be the best-performing estimator
for dealing with endogeneity in the field of corporate governance, especially with panel data
(Chapple & Humphrey, 2014; Nguyen et al., 2015; Sila et al., 2016; Wintoki et al., 2012). The
DPS-GMM technique has been used in recent research investigating the relationship between
board composition and firm outcomes (Wintoki et al, 2012; Sila, Gonzalez & Hagendorff, 2015;
Wiley & Monllor-Tormos, 2018).
Following prior research our model specification is below:
𝐹𝑃𝑖𝑡 = 𝛼 + ∑ 𝛾𝑝𝐹𝑃𝑖𝑡−𝑝
𝑝
+ 𝛽𝐶𝐺𝑖𝑡 + 𝛿𝐹𝐶𝑖𝑡 + 𝑦𝑒𝑎𝑟𝑖 + 𝜂𝑖 + 𝜖𝑖𝑡 𝑝 = 1, … . . , 𝑠
The index i in our model specification refers to each firm and the index t refers to the year. FP
are the firm performance variables. CG are the corporate governance variables – the independent
variable of interest (number of female directors) and the other control variables (see table 2) .
FC are the firm characteristics control variables (see table 2). 𝜂𝑖 is a firm-specific time invariant
effect representing unobserved characteristics of the firm influencing its performance, and εit is
the error term. yeari are the year dummy variables.
Results
We first present some descriptive statistics of our sample and then proceed to present the
results from our United States sample, which is the main thrust of our study, followed by the
results from our European and Asian sample.
17
Descriptive Statistics
Table 3 shows the descriptive statistics for our U.S., Europe and Asian samples. About
71% of the firms in our U.S. sample, 94% of the firms in our European sample and 54% of the
firms in our Asia sample, had at least one female director. The maximum number of female
directors in our U.S. sample was 8 while in our European sample it was 9 and in our Asian
sample it was 6. The average female board room representation in Europe was double (24%)
that of the US (12.5%) and was lowest in Asia (8%). The average board size was higher in
Europe and Asia (11) than in the U.S. (9). The mean number of independent directors is similar
between Europe and the U.S. (7) but lower in Asia (5). We also observe large variation in the
financial performance measures especially ROA and ROE. These descriptive statistics are in
line with prior research (e.g. Sila et al, 2016).
---------------------------------
Insert Table 3 about here
---------------------------------
Tables 4 - 6 shows some key statistics by number of female directors for the U.S., Europe
and Asian samples. We find that there are on an average more female directors on larger and
more independent boards in the U.S. and Europe, but the relationship is not very clear in Asia.
This suggests that companies that are more mature might tend to appoint more female directors.
We do not see a clear monotonically increasing relationship between number of female directors
and financial performance measures in any of the regions. Interestingly in the U.S. sample there
seems to be spike in the performance measures when there are 7 female directors on the board,
but there seems to be a decline in performance measures at around 5 female directors in our
European and Asian samples.
---------------------------------
Insert Tables 4 - 6 about here
18
---------------------------------
Tables 7 - 9 shows some key measures by time for the U.S., Europe and Asian samples.
We find that the total number of female directors rises steadily from 2008 to 2018 in all our
samples. The increase is highest in Europe where we see close to a 100 fold increase from 2008
to 2018, while in Asia there is close to a 15 fold increase and in the U.S. the number of female
directors have tripled from 2008 to 2018. But, the mean percentage of female directors seems to
have remained more or less constant in the U.S. and Asia with an uptick only in 2017 and 2018,
while in Europe we see a fivefold increase from 2008 to 2018. The mean percentage of female
executives, mean board size, and mean number of independent directors all remained constant
throughout the 10 year period in the U.S. sample. But, we do see large increases in number of
female CEOs, number of female board chairpersons and CEO duality from 2008 to 2018 in
Europe and U.S. It is interesting to note that the Asian sample seems to indicate that the female
director being a chairperson is a rarity.
---------------------------------
Insert Tables 7 - 9 about here
---------------------------------
The descriptive statistics provide clear evidence of companies increasingly appointing
female directors to the board and increase in women CEOs and board chairpersons in the past
eleven years. This broad trend is in line with numerous research findings and articles in the
popular press. But, caution should be exercised in interpreting our comparative evidence across
regions, as our Asian and European sample sizes are much smaller than our U.S. sample size.
Nevertheless, the descriptive statistics discussed above provide many interesting trends in board
gender diversity and firm characteristics and performance across the U.S., Europe and Asia.
19
Is there a positive relationship between board gender diversity and firm performance in
U.S. firms?
Table 10 presents the results of fitting the DPS-GMM model to our U.S. sample. We use
two lags of the firm performance measures (the dependent variable) in estimating our model. All
independent variables are treated as endogenous, except the year dummies, and are instrumented
by two of their past (lagged) values. We find no evidence of a positive relationship between
number of female board directors and firm performance as measured by Tobin’s Q. The
coefficient is in fact very small and negative, but not statistically significant, thus indicating that
there is no relationship between BGD and FP. We conduct robustness checks using the
accounting measures of ROA and ROE as proxies for firm performance and again find no
evidence of any relationship between BGD and FP.
---------------------------------
Insert Table 10 about here
---------------------------------
Another interesting result to note is that the percentage of female executives and the
presence of a female CEO are statistically significant (p < 0.05) for the market based measure of
performance (Tobin’s Q) but not for the accounting based measures of performance (ROA,
ROE). It is also interesting to note that the coefficient for female CEO is negative, indicating
that firm performance as measured by Tobin’s Q goes down if the company has a female CEO.
We note this finding just as an interesting aside that is not related to our main research question
and caution that further research needs to be conducted before any conclusions can be drawn
regarding the relationship between female CEOs and firm performance.
The results of the Sargan test of overidentifying restrictions, with the null hypothesis that
all the instruments variables are exogenous, shows that the null hypothesis cannot be rejected. In
20
other words the two past values of the independent variables, which were used as instrument
variables, are exogenous. The Arellano-Bond test for autocorrelation shows evidence of strong
first order autocorrelation but not second order autocorrelation in the residuals.
We conduct a robustness check of our results using the percentage of female directors
instead of the absolute number of female directors as our main independent variable. The results
of this analysis is presented in table 11. We again find no evidence of a positive relationship
between percentage of female directors and firm financial performance (Tobin’s Q, ROA, ROE).
Again the coefficient for percentage of female directors is very small, negative and not
statistically significant, indicating no relationship between BGD and FP. We note similar
statistically significant results for percentage of female executives and female CEO as described
earlier.
---------------------------------
Insert Table 11 about here
---------------------------------
Is there a critical mass effect at 30% female directors in the relationship between BGD and
FP in U.S. firms?
To address this question we added a dummy independent variable for 30% critical mass
to our model. We also added an interaction variable between number of female directors and
critical mass. Since some prior research studies (e.g. Wiley & Monllorr-Tormos, 2018) have
reported a “U” shaped nonlinear quadratic relationship between BGD and FP we included the
square of the number of female directors as an independent variable to test for a quadratic
relationship.
Table 12 shows the results of the DPS-GMM model with the above described variables
added. We do not find any evidence of the existence of a critical mass at 30%. The critical mass
21
dummy and the interaction variable are not statistically significant. We do find weak evidence (p
< 0.1) of a nonlinear quadratic relationship between number of female directors and Tobin’s Q.
---------------------------------
Insert Table 12 about here
---------------------------------
We conducted robustness checks using the ROA and ROE as dependent variables and
find similar results (see table 12). The nonlinear relationship is not evidenced with ROA, but
only with Tobin’s Q and ROE and is only weakly significant. We conduct further robustness
checks (table 13) by replacing number of female directors with percentage of female directors
and find exactly the same results. We further tested various levels of critical mass (20%, 40%,
50%) and found no evidence of a critical mass at any of those levels. As discussed previously, in
our descriptive statistics we found an uptick in performance when the number of female directors
was 7, so, we wanted to test whether there is evidence of critical mass at 7 female directors. We
fit our model with dummies for 3,4,5,6, and 7 female directors respectively and found no
evidence of critical mass at any of these levels. For the sake of brevity we have not reported the
results in tabular form for the various levels of critical mass, but, the results are available on
request.
---------------------------------
Insert Table 13 about here
---------------------------------
Thus, we find no evidence of the existence of a critical mass in the BGD-FP relationship,
but we do find weak evidence of a quadratic relationship between BGD and FP.
The analysis of our U.S. sample leads us to reject our hypotheses that a positive
relationship exists between BGD and FP and also that there exists a critical mass at 30% that
22
moderates the BGD-FP relationship. Now we proceed to present the results of our analysis for
the European and Asian samples.
Is there a positive relationship between board gender diversity and firm performance in
European firms?
Table 14 shows the results of fitting the DPS-GMM model described above to our
European sample. Similar to the U.S. we find no evidence of a positive relationship between
BGD and FP. The coefficient (relationship) is positive, unlike in the U.S. sample, but very small
and not statistically significant, indicating no relationship between BGD and FP. The robustness
checks using the accounting measures of ROA and ROE as proxies for firm performance again
find no evidence of a positive relationship between BGD and FP. The coefficients are again
small and not statistically significant indicating that there is no relationship between BGD and
FP. Unlike the U.S. sample we do not find any statistically significant association between
percentage of female executives and female CEO on firm performance.
---------------------------------
Insert Table 14 about here
---------------------------------
The results of the Sargan test of overidentifying restrictions shows that the instrument
variables are exogenous. The Arellano-Bond test for autocorrelation shows evidence of first
order autocorrelation but not as strong as in the U.S. sample.
Robustness checks using percentage of female directors instead of the number of female
directors confirm our finding of no evidence of any relationship between BGD and FP. For
brevity, we do not present a table with the results of this robustness check, but, the results are
available on request.
23
Is there a critical mass effect at 30% female directors in the relationship between BGD and
FP in European firms?
Table 15 presents the results of fitting the critical mass model which includes a dummy
variable for critical mass 30%, an interaction variable between critical mass and BGD and a
number of female directors squared variable. We do not find evidence of a 30% critical mass nor
a “U” shaped relationship between BGD and FP as measured by Tobin’s Q.
---------------------------------
Insert Table 15 about here
---------------------------------
Robustness checks with ROA and ROE as measures of firm performance show no
evidence of critical mass and a quadratic relationship when using ROA as a proxy for firm
performance, but show weak evidence (p < 0.1) of the existence of a critical mass at 30% and a
nonlinear quadratic relationship between BGD and ROE (see table 15).
We conducted further robustness checks by replacing number of female directors with
percentage of female directors and find similar results. We further tested various levels of
critical mass (20%, 40%, 50%) and critical mass of number of female directors (3, 4, 5, 6, 7) and
found no evidence of a critical mass at any of those levels. The results of these robustness
checks are not tabulated but are available on request.
Thus, the results from analyzing our European sample lead us to reject our hypotheses
that a positive relationship exists between BGD and FP and also that there exists a critical mass
at 30% that moderates the BGD-FP relationship. The evidence shows that there is in fact no
relationship between BGD and FP.
24
Is there a positive relationship between board gender diversity and firm performance in
Asian firms?
Table 16 presents the results of fitting our model to the Asian sample. Similar to U.S.
and Europe we find no evidence of a positive relationship between BGD as proxied by number
of female directors and FP as measured by Tobin’s Q. The coefficient of BGD is negative but
not statistically significant, thus indicating no association between BGD and FP.
---------------------------------
Insert Table 16 about here
---------------------------------
Similar to the other samples, the Sargan test confirms that the variables used as
instruments in our model are exogenous and thus valid. Similar to the European sample the first
order autocorrelations are mild and there is no evidence of second order autocorrelation.
The robustness checks using ROA and ROE as proxies for firm performance again find
no evidence of any relationship between BGD and FP (see table 16). In line with the other
samples, robustness checks using percentage of female directors shows very similar results and
confirms our finding of no statistically significant association between BGD and FP in our Asian
sample.
Is there a critical mass effect at 30% female directors in the relationship between BGD and
FP in Asian firms?
Table 17 shows the results of fitting the critical mass model to the Asian sample. We do
not find any evidence of a 30% critical mass nor a “U” shaped relationship between BGD and FP
as measured by Tobin’s Q.
---------------------------------
Insert Table 17 about here
---------------------------------
25
Robustness checks with ROA, ROE, percentage of female directors and various values
for critical mass, all, confirm our finding of no evidence of critical mass nor a “U” shaped
relationship between BGD and FP.
Thus, in summary, we find no evidence of any relationship between BGD and FP across
our U.S., European and Asian samples. We also find no evidence of the existence of a critical
mass at any level in the relationship between BGD and FP. Furthermore we do not find any
evidence of a nonlinear quadratic (U shaped) relationship between BGD and FP.
Discussion
Our study uses one of the largest and the most recent sample that we are aware of in the
literature, to investigate the relationship between board gender diversity and firm performance.
We also use a robust statistical methodology that takes into account endogeneity biases that can
cast doubt on results if not properly accounted for. Our results lead us to reject our hypothesis
that there is a positive relationship between BGD and FP and that the relationship is quadratic
with a moderating critical mass of 30%. We do not find any relationship between BGD and FP
and thus fall into the “neutral” category of the empirical literature on the relationship between
BGD and FP and are consistent with studies such as Carter et al. (2010), Rose (2007), Shrader,
Blackburn, & Iles (1997). We note that our sample size is much larger and more comprehensive
than all of the studies in the “neutral” category of the literature and arguably our methodology is
more robust. Our findings are also in line with the meta-analysis (Post & Byron, 2015; Pletzer,
Nikolova, Kedzior, and Voelpel, 2015) that found close to zero or no relationship between BGD
and FP. Thus, we add to the empirical literature on BGD and FP with a comprehensive analysis
employing robust methodology and using one of the largest, most current samples spanning three
regions of the world. We contribute to the yet unsettled debate on whether increased board
26
gender diversity leads to increased firm performance and bring a more current and
comprehensive answer to this question.
We also add to the less abundant literature on the existence of a critical mass in board
gender diversity. Our finding of no evidence of critical mass contradicts extant literature (Wiley
& Monllor-Tormos, 2018; Strydom et al., 2016; Joecks et al., 2013). All of these studies used
very small sample sizes (in the hundreds) and were also regional or restricted to certain sectors
(one in Germany, another in Australia, another restricted to technology and finance sectors).
These studies also do not use recent data (the most recent in these studies is 2013). To the best
of our knowledge, our study is the largest study to date that address the question of the existence
of a critical mass using the most recent data. Thus we make a significant contribution to the
literature on the existence of a critical mass in the relationship between board gender diversity
and firm performance.
We caution against a broad interpretation of our results as board gender diversity being
undesirable to a company as it does not affect firm financial performance. There are numerous
other non-financial reasons why gender diversity in boards is highly desirable. Moreover, we do
not capture any of the psychological impacts of greater diversity such as employee morale, etc.
in our model. Thus, our study simply points out that there is no evidence of any impact of
increased board gender diversity on firm financial performance based on our methodology in our
large recent sample and does not take any position on whether board gender diversity is desirable
or not.
Limitations and Work in Progress
We discuss some of the limitations of the current study as presented above and outline
the work in progress to address some of these limitations. Our Asian sample and European
27
samples are not as large as our American sample and hence the results we have presented for
Europe and Asia may not be as strong as the ones for the U.S. We are currently in the process of
gathering more data for Asia and Europe to increase our sample size. Though we have included
many control variables (more than most studies in the literature), there is always scope for
improving and expanding the list of control variables. We are working on including other
macroeconomic and firm characteristics variables such as capital expenditure, R&D expenditure
etc. We are also working on extending our analysis to include exploring the relationship
between BGD and FP in various different industries segments and more regions of the world.
Conclusion
In the past decade there has been increasing focus on board gender diversity all over the
world and in particular in the U.S. Many U.S. firms are under increasing pressure to appoint
more female board members and improve gender diversity on boards. Some countries, such as
Norway, have imposed quotas for female directors. Although there presently is no mandatory
gender quota in the US, public opinion, pressure from the media, shareholders and other
stakeholders, along with SEC disclosure rules are likely to drive US firms to continue to increase
board gender diversity. The extant literature provides inconsistent evidence regarding the impact
of increased board gender diversity on firm performance. With a large sample of over 3000
firms and a recent time frame of the past eleven years (2008 – 2018) our comprehensive study
contributes to this debate by investigating the relationship between boardroom gender diversity
and firm financial performance in the U.S., Europe and Asia using a robust statistical method
that takes into account endogeneity bias. We find no evidence of any relationship between board
gender diversity and firm financial performance in any of the three regions. Thus, we conclude
that in our sample there is no relationship between the number of female directors on the board
28
and firm financial performance. Moreover we find no evidence of a critical mass of female
directors beyond which firm performance starts to improve. We stress that our finding of no
empirical evidence of a positive impact on firm performance from increased board gender
diversity does not mean that board gender diversity is undesirable. The case for greater board
gender diversity should also rest on fairness and gender equality rather than on pure economic
and financial considerations.
29
References
Adams, R. B., & Ferreira, D. (2009). Women in the boardroom and their impact on governance and
performance. Journal of Financial Economics, 94, 291-309.
Adams, R. B., & Funk, P. (2012). Beyond the glass ceiling: Does gender matter? Management Science,
58, 219-235.
Adams, R. B., & Kirchmaier, T. (2016). Women on boards in finance and STEM industries. American
Economic Review, 106, 277-281.
Ahern, K. R., & Dittmar, A. K. (2012). The changing of the boards: The impact on firm valuation of
mandated female board representation. Quarterly Journal of Economics, 127, 137-197.
Alderfer, C. P. (1986). The invisible director on corporate boards. Harvard Business Review, 64(6), 38-
50.
Anderson, R. C., Reeb, D. M., Upadhyay, A., & Zhao, W. (2011). The economics of director
heterogeneity. Financial Management, 40(1), 5-38.
Arellano, M., & Bover, O. (1995). Another look at the instrumental variable estimation of error-
components models. Journal of Econometrics, 68, 29-51.
Ashforth, B. E., & Mael, F. (1989). Social identity theory and the organization. Academy of management
review, 14(1), 20-39.
Barroso, C., Villegas, M. M., & Perez-Calero, L. (2011). Board influence on a firm’s internationalization.
Corporate Governance: An International Review, 19, 351-367.
Bart, C., & McQueen, G. (2013). Why women make better directors. International Journal of Business
Governance and Ethics, 8(1), 93-99.
Bedard, J., Chtourou, S. M., & Courteau, L. (2004). The effect of audit committee expertise,
independence, and activity on aggressive earnings management. Auditing: A Journal of Practice &
Theory, 23(2), 13-35.
Berscheid, E., & Walster, E. H. (1969). Interpersonal attraction. Reading, MA: Addison-Wesley.
Bhagat, S., & Bolton, B. (2008). Corporate governance and firm performance. Journal of Corporate
Finance, 14, 257-273.
Bilimoria, D., & Wheeler, J. V. (2000). Women corporate directors: Current research and future
directions. Women in management: Current research issues, 2(10), 138-163.
Blundell, R., & Bond, S. (1998). Initial conditions and moment restrictions in dynamic panel data models.
Journal of Econometrics, 87, 115-143.
Bøhren, Ø., & Strøm, R. Ø. (2010). Governance and politics: Regulating independence and diversity in
the board room. Journal of Business Finance & Accounting, 37(9‐10), 1281-1308.
Brewer, M. B. (1979). In-group bias in the minimal intergroup situation: A cognitive-motivational
analysis. Psychological Bulletin, 86, 307-324.
30
Burgess, Z., & Tharenou, P. (2002). Women board directors: Characteristics of the few. Journal of
Business Ethics, 37, 39-49.
Burke, R. J. (1997). Women on corporate boards of directors: A needed resource. In Women in corporate
management (pp. 37-43). Springer, Dordrecht.e24xc
Byrne, D. E. (1971). The attraction paradigm (Vol. 11). New York, NY: Academic Press.
Campbell, K., & Minguez-Vera, A. (2008). Gender diversity in the boardroom and firm financial
performance. Journal of Business Ethics, 83, 435-451.
Carlsson, G., & Karlsson, K. (1970). Age, cohorts and the generation of generations. American
Sociological Review, 35, 710-718.
Carter, D. A., D’Souza, F., Simkins, B. J., & Simpson, W. G. (2010). The gender and ethnic diversity of
US boards and board committees and firm financial performance. Corporate Governance: An
International Review, 18, 396-414.
Carter, D. A., D’Souza, F., Simkins, B. J., & Simpson, W. G. (2007). The diversity of corporate board
committees and financial performance (Working Paper, 89-154). Stillwater: Oklahoma State University.
Carter, D. A., Simkins, B. J., & Simpson, W. G. (2003). Corporate governance, board diversity, and firm
value. Financial Review, 38(1), 33-53.
Chapple, L., & Humphrey, J. E. (2014). Does board gender diversity have a financial impact? Evidence
using stock portfolioperformance. Journal of Business Ethics, 122, 709-723.
Cohen, L. E., Broschak, J. P., & Haveman, H. A. (1998). And then there were more? The effect of
organizational sex composition on the hiring and promotion of managers. American Sociological Review,
63, 711-727.
Dahlerup, D. (2006). The story of the theory of critical mass. Politics & Gender, 2, 511-522.
Dalton, D. R., & Dalton, C. M. (2010). Women and corporate boards of directors: The promise of
increased, and substantive, participation in the post Sarbanes-Oxley era. Business Horizons, 53, 257-268.
Darmadi, S. (2011). Board diversity and firm performance: the Indonesian evidence. Corporate ownership
and control Journal, 8.
de Luis-Carnicer, P., Martínez-Sánchez, Á., Pérez-Pérez, M., & José Vela-Jiménez, M. (2008). Gender
diversity in management: curvilinear relationships to reconcile findings. Gender in Management: An
International Journal, 23(8), 583-597.
Delis, M. D., Gaganis, C., Hasan, I., & Pasiouras, F. (2017). The effect of board directors from countries
with different genetic diversity levels on corporate performance. Management Science, 63, 231-249.
Desvaux, G., Devillard-Hoellinger, S., & Baumgarten, P. (2007). Women matter: Gender diversity, a
corporate performance driver. McKinsey.
Dezso, C. L., & Ross, D. G. (2012). Does female representation in top management improve firm
performance? A panel data investigation. Strategic Management Journal, 33, 1072-1089.
Dobbin, F., & Jung, J. (2011). Corporate board gender diversity and stock performance: The competence
gap or institutional investor bias. North Carolina Law Review, 89, 809-838.
31
Elkinawy, S., & Stater, M. (2011). Gender differences in executive compensation: Variation with board
gender composition and time. Journal of Economics and Business, 63(1), 23-45.
Erhardt, N. L., Werbel, J. D., & Shrader, C. B. (2003). Board of director diversity and firm financial
performance. Corporate Governance: An International Review, 11(2), 102-111.
Farrell, K. A., & Hersch, P. L. (2005). Additions to corporate boards: The effect of gender. Journal of
Corporate Finance, 11(1), 85-106.
Flannery, M. J., & Hankins, K. W. (2013). Estimating dynamic panel models in corporate finance.
Journal of Corporate Finance, 19(C), 1-19.
Francoeur, C., Labelle, R., & Sinclair-Desgagne, B. (2008). Gender diversity in corporate governance and
top management. Journal of Business Ethics, 81, 83-95.
Garnero, A., Kampelmann, S., & Rycx, F. (2014). The heterogeneous effects of workforce diversity on
productivity, wages, and profits. Industrial Relations: A Journal of Economy and Society, 53, 430-477.
Groysberg, B., & Bell, D. (2013). Dysfunction in the boardroom. Harvard Business Review, 91(6), 89-97.
Hambrick, D. C. (2007). Upper Echelons Theory: An Update. The Academy of Management Review,
334-343.
Hambrick, D. C., & Mason, P. A. (1984). Upper echelons: The organization as a reflection of its top
managers. Academy of management review, 9(2), 193-206.
Harris, M., & Raviv, A. (2008). A theory of board control and size. The Review of Financial Studies,
21(4), 1797-1832.
Haslam, S. A., Ryan, M. K., Kulich, C., Trojanowski, G., & Atkins, C. (2010). Investing with prejudice:
The relationship between women’s presence on company boards and objective and subjective measures of
company performance. British Journal of Management, 21, 484-497.
Hermalin, B. E., & Weisbach, M. S. (2001). Boards of directors as an endogenously determined
institution: A survey of the economic literature. Economic Policy Review, 9(1), 7-26.
Hillman, A. J., Cannella Jr, A. A., & Harris, I. C. (2002). Women and racial minorities in the boardroom:
How do directors differ?. Journal of management, 28(6), 747-763.
Hillman, A. J., & Dalziel, T. (2003). Boards of directors and firm performance: Integrating agency and
resource dependence perspectives. Academy of Management Review, 28, 383-396.
Hillman, A. J., Shropshire, C., & Cannella, A. A. (2007). Organizational predictors of women on
corporate boards. Academy of Management Journal, 50, 941-952.
Hitt, M. A., Jackson, S. E., Carmona, S., Bierman, L., Shalley, C. E., & Wright, M. (2017). The oxford
handbook of strategy implementation. Oxford University Press.
Hogg, M. A., Turner, J. C., & Davidson, B. (1990). Polarized norms and social frames of reference: A test
of the self-categorization theory of group polarization. Basic and Applied Social Psychology, 11(1), 77-
100.
32
Holm, C., & Scholer, F. (2010). Reduction of asymmetric information through corporate governance
mechanisms—The importance of ownership dispersion and exposure toward the international capital
market. Corporate Governance: An International Review, 18(1), 32-47.
Hull, C. E., & Rothenberg, S. (2008). Firm performance: The interactions of corporate social performance
with innovation and industry differentiation. Strategic Management Journal, 29, 781-789.
Huse, M., & Solberg, A. G. (2006). Gender-related boardroom dynamics: How Scandinavian women
make and can make contributions on corporate boards. Women in Management Review, 21(2), 113-130.
Ibarra, H. (1993). Personal networks of women and minorities in management: A conceptual framework.
Academy of Management Review, 18(1), 56-87.
Jehn, K. A., Northcraft, G. B., & Neale, M. A. (1999). Why differences make a difference: A field study
of diversity, conflict, and performance in workgroups. Administrative Science Quarterly, 44, 741-763.
Jia, M., & Zhang, Z. (2013). Critical mass of women on BODs, multiple identities, and corporate
philanthropic disaster response: Evidence from privately owned Chinese firms. Journal of Business
Ethics, 118, 303-317.
Joecks, J., Pull, K., & Vetter, K. (2013). Gender diversity in the boardroom and firm performance: What
exactly constitutes a “critical mass?” Journal of Business Ethics, 118, 61-72.
Johnson, J. L., Daily, C. M., & Ellstrand, A. E. (1996). Boards of directors: A review and research
agenda. Journal of Management, 22, 409-438.
Jones, P., Hillier, D., & Comfort, D. (2013). That’s the spirit: Exploring the approach of the world’s
leading spirits’ producers to corporate social responsibility. Journal of Public Affairs, 13(1), 3-11.
Jonsdottir, T., Singh, V., Terjesen, S., & Vinnicombe, S. (2015). Director identity in pre- and post-crisis
Iceland: Effects of board life stage and gender. Gender in Management: An International Journal, 30,
572-594.
Kanter, R. M. (1977). Some effects of proportions on group life: Skewed sex ratios and responses to
token women. American Journal of Sociology, 82, 965-990.
Konrad, A. M., Kramer, V., & Erkut, S. (2008). Critical mass: The impact of three or more women on
corporate boards. Organizational Dynamics, 37, 145-164.
Kramer, V. W., Konrad, A. M., Erkut, S., & Hooper, M. J. (2006). Critical mass on corporate boards:
Why three or more women enhance governance. Boston, MA: Wellesley Centers for Women.
Krishnan, H. A., & Park, D. (2005). A few good women—on top management teams. Journal of business
research, 58(12), 1712-1720.
Larcker, D. F., So, E. C., & Wang, C. C. Y. (2013). Boardroom centrality and firm performance. Journal
of Accounting and Economics, 55, 225-250.
Luckerath-Rovers, M. (2013). Women on boards and firm performance. Journal of Management &
Governance, 17, 491- 509.
Makri, M., & Scandura, T. A. (2010). Exploring the effects of creative CEO leadership on innovation in
high-technology firms. Leadership Quarterly, 21, 75-88.
33
Masulis, R. W., Wang, C., & Xie, F. (2007). Corporate governance and acquirer returns. Journal of
Finance, 62, 1851-1889.
Masulis, R. W., Wang, C., & Xie, F. (2012). Globalizing the boardroom—The effects of foreign directors
on corporate governance and firm performance. Journal of Accounting and Economics, 53, 527-554.
Matsa, D. A., & Miller, A. R. (2013). A female style in corporate leadership? Evidence from quotas.
American Economic Journal: Applied Economics, 5(3), 136-169.
McDowell, L. (2011). Making a drama out of a crisis: Representing financial failure, or a tragedy in five
acts. Transactions of the Institute of British Geographers, 36, 193-205.
Miller, T., & Triana, M. D. C. (2009). Demographic diversity in the boardroom: Mediators of the board
diversity–firm performance relationship. Journal of Management Studies, 46, 755-786.
Milliken, F. J., & Martins, L. L. (1996). Searching for common threads: Understanding the multiple
effects of diversity in organizational groups. Academy of Management Review, 21, 402-433.
Mínguez-Vera, A., & Martin, A. (2011). Gender and management on Spanish SMEs: an empirical
analysis. The International Journal of Human Resource Management, 22(14), 2852-2873.
Musteen, M., Datta, D. K., & Herrmann, P. (2009). Ownership structure and CEO compensation:
Implications for the choice of foreign market entry modes. Journal of International Business Studies, 40,
321-338.
Nguyen, T., Locke, S., & Reddy, K. (2015, May). Does boardroom gender diversity matter? Evidence
from a transitional economy. International Review of Economics & Finance, 37, 184-202.
Ntim, C. G. (2015). Board diversity and organizational valuation: Unravelling the effects of ethnicity and
gender. Journal of Management & Governance, 19, 167-195.
Ostergaard, C. R., Timmermans, B., & Kristinsson, K. (2011). Does a different view create something
new? The effect of employee diversity on innovation. Research Policy, 40, 500-509.
Oxelheim, L., Gregorič, A., Randoy, T., & Thomsen, S. (2013). On the internationalization of corporate
boards: The case of Nordic firms. Journal of International Business Studies, 44, 173-194.
Perez-Calero Sanchez, L., Villegas-Perinan, M. D. M., & Barroso-Castro, C. (2013). The board of
directors and international decision-making. ESIC Market Economics and Business Journal, 44(3), 59-81.
Perrault, E. (2015). Why does board gender diversity matter and how do we get there? The role of
shareholder activism in deinstitutionalizing old boys’ networks. Journal of Business Ethics, 128, 149-165.
Pletzer, J. L., Nikolova, R., Kedzior, K. K., & Voelpel, S. C. (2015). Does gender matter? Female
representation on corporate boards and firm financial performance-a meta-analysis. PloS one, 10(6),
e0130005.
Post, C., & Byron, K. (2015). Women on boards and firm financial performance: A meta-analysis.
Academy of Management Journal, 58, 1546-1571.
Post, C., Rahman, N., & Rubow, E. (2011). Green governance: Boards of directors’ composition and
environmental corporate social responsibility. Business & Society, 50, 189-223.
Powell, G. N., & Graves, L. M. (2003). Women and men in management. Thousand Oaks, CA: Sage.
34
Priem, R. L., Lyon, D. W., & Dess, G. G. (1999). Inherent limitations of demographic proxies in top
management team heterogeneity research. Journal of Management, 25, 935-953.
Rhode, D. L. (2016). Women and leadership. New York, NY: Oxford University Press.
Rhode, D. L., & Packel, A. K. (2014). Diversity on corporate boards: How much difference does
difference make. Delaware Journal of Corporate Law, 39, 377-425.
Roberson, Q. M., & Park, H. J. (2007). Examining the link between diversity and firm performance the
effects of diversity reputation and leader racial diversity. Group & Organization Management, 32, 548-
568.
Roodman, D. (2009). A note on the theme of too many instruments. Oxford Bulletin of Economics and
Statistics, 71, 135-158.
Rose, C. (2007). Does female board representation influence firm performance? The Danish evidence.
Corporate Governance: An International Review, 15, 404-413.
Rose, C., Munch-Madsen, P., & Funch, M. (2013). Does board diversity really matter? Gender does not,
but citizenship does. International Journal of Business Science and Applied Management, 8(1), 15-27.
Rosener, J. B. (1990). Ways women lead. Harvard Business Review, 68(6), 119-125.
Ryan, M. K., & Haslam, S. A. (2007). The glass cliff: Exploring the dynamics surrounding the
appointment of women to precarious leadership positions. Academy of Management Review, 32, 549-572.
Sabatier, M. (2015). A women’s boom in the boardroom: effects on performance?. Applied Economics,
47(26), 2717-2727.
Salancik, G. R., & Pfeffer, J. (1978). A social information processing approach to job attitudes and task
design. Administrative science quarterly, 224-253.
Sanders, W. G., & Carpenter, M. A. (1998). Internationalization and firm governance: The roles of CEO
compensation, top team composition, and board structure. Academy of Management Journal, 41, 158-
178.
Schultz, E. L., Tan, D. T., & Walsh, K. D. (2010). Endogeneity and the corporate governance-
performance relation. Australian Journal of Management, 35, 145-163.
Schwab, A., Werbel, J. D., Hofmann, H., & Henriques, P. L. (2016). Managerial gender diversity and
firm performance: An integration of different theoretical perspectives. Group & Organization
Management, 41(1), 5-31.
Shrader, C. B., Blackburn, V. B., & Iles, P. (1997). Women in management and firm financial
performance: An exploratory study. Journal of Managerial Issues, 9, 355-372.
Siciliano, J. I. (1996). The relationship of board member diversity to organizational performance. Journal
of Business Ethics, 15, 1313-1320.
Sila, V., Gonzalez, A., & Hagendorff, J. (2016). Women on Board: Does boardroom gender diversity
really affect firm risk? Journal of Corporate Finance, 36(C), 26-53.
Singh, V., Vinnicombe, S., & Johnson, P. (2001). Women directors on top UK boards. Corporate
Governance: An International Review, 9(3), 206-216.
35
Singla, C., George, R. P., & Veliyath, R. (2010). Internationalization, family business and corporate
governance: An emerging market perspective. Paper presented at the Academy of Management, Best
Papers Proceedings, 2010(1), 1-6. Retrieved from http://proceedings.aom.org/content/2010/1/1.89.short
Strydom, M., Au Yong, H. H., & Rankin, M. (2016). A few good (wo) men? Gender diversity on
Australian boards. Australian Journal of Management, 42, 404-427.
Sun, S., Zhu, J., & Ye, K. (2015). Board openness during an economic crisis. Journal of Business Ethics,
129, 363-377.
Tajfel, H. (1978). Social categorization, social identity and social comparison. London, England:
Academic Press.
Tajfel, H., & Turner, J. (1986). The social identity theory of inter-group behaviour. In S. Worchel & L.
W. Austin (Eds.), Psychology of intergroup relations (pp. 33-47). Chicago, IL: Nelson-Hall.
Torchia, M., Calabro, A., & Huse, M. (2011). Women directors on corporate boards: From tokenism to
critical mass. Journal of Business Ethics, 102, 299-317.
Turner, J. C., Hogg, M. A., Oakes, P. J., Reicher, S. D., & Wetherell, M. S. (1987). Rediscovering the
social group: A self-categorization theory. Oxford, England: Basil Blackwell.
Van Staveren, I. (2014). The Lehman Sisters hypothesis. Cambridge Journal of Economics, 38, 995-
1014.
Vroom, V. H., & Pahl, B. (1971). Relationship between age and risk taking among managers. Journal of
Applied Psychology, 55, 399-405.
Watson, J., & Robinson, S. (2003). Adjusting for risk in comparing the performances of male-and female-
controlled SMEs. Journal of business venturing, 18(6), 773-788.
Wiley, C., & Monllor-Tormos, M. (2018). Board gender diversity in the STEM&F sectors: the critical
mass required to drive firm performance. Journal of Leadership & Organizational Studies,
1548051817750535.
Wintoki, M. B., Linck, J. S., & Netter, J. M. (2012). Endogeneity and the dynamics of internal corporate
governance. Journal of Financial Economics, 105, 581-606.
Yermack, D. (1996). Higher market valuation of companies with a small board of directors. Journal of
Financial Economics, 40, 185-211.
Zahra, S. A., Priem, R. L., & Rasheed, A. A. (2007). Understanding the causes and effects of top
management fraud. Organizational Dynamics, 36, 122-139.
Zahra, S. A., & Stanton, W. W. (1988). The implications of board of director’s composition for corporate
strategy and performance. International Journal of Management, 5, 229-236.
Zhou, Q., Faff, R., & Alpert, K. (2014). Bias correction in the estimation of dynamic panel models in
corporate finance. Journal of Corporate Finance, 25, 494-513.
36
Table 1
Summary of literature
Source: The Oxford Handbook of Strategy Implementation by Michael A. Hitt, Susan E. Jackson, Salvador
Carmona, Leonard Bierman, Christina E. Shalley, Mike Wright (2017)
Table 2
Variable definitions
Dependent Variables Tobin’s Q Ratio of the market value of the company’s assets to
the replacement cost or book value of the company’s
assets. ROA Net income divided by the book value of total assets ROE Net income divided by shareholders equity
Independent Variables No of female directors Number of female directors on the board Percentage of female directors Percentage of female directors on the board
Control Variables Percentage of female executives Percentage of female executives in the company No of female executives Number of female executives in the company Percentage of females in the workforce Percentage of women in the entire workforce Board size Size of the board
Number Research Study Year Region
Research
Period No_of_org
Mean
Proportion
Of Women
on Board TobinQ ROA
1 Shrader, Blackburn & Iles 1997 US 1992-1993 200 0.08 non log - negative -n.s
2
Carter, D' Souza, Simkins &
Simpson 2003 US
1998-2002 641
0.12 positive, p- n.s positive, p<0.05
3 Carter, Simkins & Simpson 2003 US 1997 638 0.1 positive, p<0.05
4 Erhardt et al. 2003 Us 1997-1998 112 0.24 positive, p<.001
5 Bonn 2004 Japan 1998-1999 169 0 negative, p= n.s
6 Campbell & Minguez- Vera 2008 Spain 1995-2000 68 0.03 positive, p<0.05
7 Adams & Ferreira 2009 US 1996-2003 1939 0.08 negative, p<.10 negative, p<.10
8 Miller & del Carmen Triana 2009 US 2003-2005 326-432 0.13 ROI+ROS = positive,ns
9 Bohren & Strom 2010 Norway 1989-2002 229 0.05 negative, p<0.05
10 Haslam et al 2010 UK 2001-2005 126 0.07-0.11 negative , p--n.s negative, n.s
11 Dobbin & Jung 2011 US 1997-2006 432 NA negative, p<0.05 positive, p-n.s
12 He & Huang 2011 US 2001-2007 530 0.16 negative, p<.10
13 Ahern & Dittmar 2012 Norway 2001-2009 248 0.04-.43 negative p< .01
14
Mahadeo,Soobaroyen &
Hanuman 2012 Mauritius
2007 42
0.03 positive, p<0.01
15 Darmadi 2013 Indonesia 2007 354 0.12 negative, p<0.05 negative, p-n.s
16 Joecks, Pull & Vetter 2013 Germany 2000-2005 151 0.08 positive, curlinear, p<.05
17 Ali, Ng&Kulik 2014 Australia 2011-2012 288 0.08 positive, p ns
18
Carolyn Wiley, Mireia Monllor-
Tormos 2018 US
2007-2013 1357
positive, p<0.05
37
Board meeting per year Number of board meetings per year Board average tenure Average tenure of board members in years Board average age Average age of board members Number of independent directors Number of independent directors Number of independent directors in the
audit committee
Number of independent directors in the audit committee
CEO Duality Is CEO also the chair of the board? CEO Tenure Tenure of the CEO in years Stock owned by CEO Percentage of stock owned by the CEO CEO Age Age of CEO CEO Compensation CEO total compensation Female board chairperson Is the board chairperson female? Female CEO Is the CEO female? Number of employees Total number of employees Industry Dummy variable for type of industry Aruoba-Diebold-Scotti Business
Conditions Index
Aruoba-Diebold-Scotti Business Conditions Index
Economic Policy Uncertainty (EPU) index Economic Policy Uncertainty (EPU) index
Moderating Variables Critical Mass 20% Critical mass at 20% of women directors Critical Mass 30% Critical mass at 30% of women directors Critical Mass 40% Critical mass at 40% of women directors Critical Mass 50% Critical mass at 50% of women directors Critical number of female directors 3 Critical mass at 3 women directors Critical number of female directors 4 Critical mass at 4 women directors Critical number of female directors 5 Critical mass at 5 women directors Critical number of female directors 6 Critical mass at 6 women directors Critical number of female directors 7 Critical mass at 7 women directors
Table 3
Descriptive statistics
USA Europe Asia
Mean SD Mean SD Mean SD
No of female directors 1.222 1.085 2.79 1.663 1.002 1.25
Percentage of female directors 12.53 10.6 24.18 12.54 7.881 9.058
Percentage of female executives 13.55 13.6
No of female executives 1.16 1.379 2.627 7.244
Percentage of females in the workforce 37.2 4.301 27.78 21.77
Board size 9.223 2.527 11.38 3.057 11.3 3.35
Board meeting per year 8.16 3.916 9.26 3.554 8.392 4.641
38
Board average tenure 5.72 2.041 5.157 4.024
Board average age 58.82 3.275 56.54 8.144
Number of independent directors 7.302 2.448 7.55 2.587 5.198 2.324
Number of independent directors in the audit
committee
3.836 1.129 3.52 1.145 3.442 0.9908
CEO Tenure 7.962 7.46 3.623 4.776
Stock owned by CEO 1.819 5.787 0.3832 1.5
CEO Age 57.27 7.238
Number of employees 15541 57505 70903 85578 77261 55211
Tobin’s Q 1.959 1.723 1.79 1.227 1.717 1.396
ROA 1.878 16.59 17.94 20 15.72 9.208
ROE 6.351 45.01 5.86 6.81 7.742 7.407
Aruoba-Diebold-Scotti Business Conditions
Index
-0.393 0.989 N/A N/A N/A N/A
Economic Policy Uncertainty (EPU) index 125.4 26.13 197.50 38.86 145.3 29.76
Note: The greyed out cells indicate that data was not available on the Bloomberg
Table 4
Descriptive statistics by number of females on the board (U.S. sample)
Number of female
Directors
Board
Size
No of Independent
directors
No of
Employees
Tobin’s
Q
ROA ROE
0 8 6 6212 2.05 -0.06 0.29
1 9 7 9501 1.97 1.68 4.76
2 10 8 20854 1.87 3.24 10.87
3 11 9 39030 1.85 4.33 16.91
4 12 10 66548 1.83 4.95 17.46
5 12 11 61038 1.94 5.61 18.40
6 14 11 64150 1.83 5.53 21.80
7 14 10 32414 3.26 10.28 29.74
8 17 11 46000 4.80 9.18 24.43
Table 5
Descriptive statistics by number of females on the board (Europe sample)
Number of
female
Directors
Board
Size
No of
Independent
directors
No of Employees Tobin’s Q ROA ROE
0 9 6 44136 1.89 5.97 14.41
39
1 10 7 65635 1.86 6.32 21.42
2 10 7 52763 1.77 5.63 17.14
3 11 8 68633 1.77 6.20 19.26
4 13 8 80779 1.82 6.16 17.89
5 13 8 106655 1.94 6.23 16.96
6 16 10 131082 1.45 3.41 13.03
7 15 8 96992 1.64 4.83 14.67
8 18 9 175841 1.19 1.23 9.54
9 21 6 71308 0.99 0.24 6.26
Table 6
Descriptive statistics by number of females on the board (Asia sample)
Number of
female
Directors
Board
Size
No of
Independent
directors
No of Employees Tobin’s Q ROA ROE
0 10 5 71957 1.79 7.87 13.28
1 11 5 50136 1.95 9.10 20.07
2 13 5 109757 1.53 6.61 15.74
3 14 6 139875 1.17 5.22 15.40
4 16 7 92739 1.05 6.82 14.68
5 16 8 72644 1.26 3.07 14.27
6 17 6 296584 1.05 1.20 13.32
Table 7
Descriptive statistics by time (U.S. sample)
Year No of
female
directors
Mean
Percentage
female
directors
Mean
percentage
of female
executives
Mean
board
size
Mean
indepen
dent
directors
No of
CEO
duality
No of
female
chairperson
No of
female
CEOs
2008 1004 11.6 14.9 10.1 7.9 454 9 10
2009 1205 11.2 14.4 9.8 7.7 556 11 11
2010 1295 11.0 14.1 9.6 7.5 596 15 16
2011 1865 10.2 13.4 9.2 7.2 871 36 41
2012 2028 10.6 13.3 9.1 7.2 881 38 49
2013 2191 11.0 13.3 9.1 7.2 905 51 58
2014 2456 11.7 13.4 9.1 7.2 919 54 72
2015 2813 12.7 13.5 9.1 7.2 947 67 86
2016 3180 13.7 13.5 9.1 7.2 952 76 95
2017 3443 14.8 13.5 9.1 7.3 930 82 105
2018 3778 15.8 13.5 9.1 7.3 911 84 111
40
Table 8
Descriptive statistics by time (Europe sample)
Year No of
female
directors
Mean
Percentage
female
directors
No of
female
executives
Mean
board
size
Mean
indepen
dent
directors
No of
CEO
duality
No of
female
chairperson
No of
female
CEOs
2008 6 6.10 2 11 8 0 0 0
2009 17 9.38 6 11 7 0 0 1
2010 34 10.70 19 10 7 3 0 2
2011 164 14.47 69 11 7 9 1 4
2012 281 18.28 113 11 7 19 2 4
2013 341 20.14 151 11 7 23 4 5
2014 382 22.95 151 12 8 25 4 3
2015 450 26.23 183 12 8 24 5 4
2016 522 29.18 217 11 8 22 5 7
2017 553 30.45 232 11 8 21 8 6
2018 607 31.55 258 12 8 22 10 7
Table 9
Descriptive statistics by time (Asia sample)
Year No of
female
directors
Mean
Percentage
female
directors
No of
female
executives
Mean
board
size
Mean
indepen
dent
directors
No of
CEO
duality
No of
female
chairperson
No of
female
CEOs
2008 4 3.8 3 11 5 6 0 0
2009 9 5.4 5 12 6 8 0 0
2010 15 3.9 32 11 5 9 0 1
2011 39 6.9 40 12 5 8 1 1
2012 45 7.4 43 12 5 11 0 2
2013 48 7.5 61 12 5 14 0 2
2014 54 8.5 151 12 5 13 0 3
2015 50 8.2 194 11 5 16 0 3
2016 57 9.3 193 11 5 17 0 3
2017 54 8.9 200 11 5 17 0 3
2018 60 9.6 218 11 5 16 0 3
41
Table 10
Relationship between board gender diversity and firm performance (U.S. sample)
This table reports two-step dynamic panel system GMM estimations of the natural log of Tobin’s Q, ROA and ROE
on the number of female directors and control variables. All models include year dummy variables. All independent
variables are treated as endogenous except year dummy variables. Endogenous variables are instrumented by two of
their past values. In parentheses are finite-sample robust standard errors (Windmeijer, 2005). The null hypothesis for
the Sargan test of overidentification is that all instruments are exogenous. AR(1) and AR(2) are test statistics for the
null hypothesis that there is no serial correlation of orders 1 and 2 in the first-difference residuals. *, ** and ***
denote statistical significance at 10%, 5% and 1% respectively.
Ln Tobin’s Q ROA ROE
No of female directors -0.002 (0.004) -0.042 (0.215) 0.261 (0.598)
Percentage of female executives 0.002 (0.001)** 0.021 (0.053) 0.076 (0.145)
Percentage of females in the workforce 0.001 (0.003) -0.115 (0.211) 0.265 (0.435)
Board size -0.002 (0.003) 0.004 (0.185) -0.17 (0.606)
Board average tenure -0.002 (0.001)** 0.045 (0.062) 0.267 (0.142)*
Board meeting per year -0.003 (0.001)*** -0.096 (0.03)*** -0.218 (0.089)**
Number of independent directors 0.003 (0.003) 0.107 (0.203) 0.721 (0.597)
Number of independent directors in the
audit committee 0.002 (0.002) 0.113 (0.149) 0.037 (0.381)
CEO Duality -0.009 (0.006) 0.064 (0.393) 1.841 (1.107)*
CEO Tenure 0.002 (0.002) 0.137 (0.104) 0.182 (0.303)
CEO Compensation -0.065 (0.031)** -1.351 (1.076) -0.888 (3.057)
Stock owned by CEO 0.007 (0.003)** -0.102 (0.246) -0.392 (0.672)
CEO Age -0.003 (0.002) -0.042 (0.137) -0.249 (0.321)
Female board chairperson 0.007 (0.02) -0.771 (1.021) 0.202 (3.25)
Female CEO -0.043 (0.02)** -0.714 (1.214) -1.456 (2.673)
Industry 0.016 (0.005)*** 0.631 (0.318)** -0.355 (0.726)
Number of employees -0.005 (0.003)* 0.566 (0.202)*** 1.836 (0.455)***
Aruoba-Diebold-Scotti Business
Conditions Index 0.026 (0.065) 1.19 (5.685) 3.789 (12.492)
Economic Policy Uncertainty (EPU)
index -0.001 (0.001)* -0.03 (0.039) -0.139 (0.11)
Firm performance measure lag 1 0.709 (0.031) 0.422 (0.039)*** 0.387 (0.042)***
Firm performance measure lag 2 0.012 (0.018) 0.019 (0.013) -0.032 (0.013)**
42
Observations 14896 14896 14896
Sargan Test (df = 346) 367.76 355.98 319.24
AR(1) -13.1257*** -8.94714*** -6.34417***
AR(2) -1.0369 -0.337735 0.808977
Table 11
Relationship between BGD and FP – robustness check using percentage of female directors (U.S.
sample)
This table reports two-step dynamic panel system GMM estimations of the natural log of Tobin’s Q, ROA and ROE
on the percentage of female directors and control variables. All models include year dummy variables. All
independent variables are treated as endogenous except year dummy variables. Endogenous variables are
instrumented by two of their past values. In parentheses are finite-sample robust standard errors (Windmeijer, 2005).
The null hypothesis for the Sargan test of overidentification is that all instruments are exogenous. AR(1) and AR(2)
are test statistics for the null hypothesis that there is no serial correlation of orders 1 and 2 in the first-difference
residuals. *, ** and *** denote statistical significance at 10%, 5% and 1% respectively.
Ln Tobin’s Q ROA ROE
Percentage of female directors -0.0004 (-0.0004) -0.013 (0.022) -0.018 (0.054)
Percentage of female executives 0.002 (0.001)** 0.026 (0.055) 0.109 (0.125)
Percentage of females in the workforce 0.001 (0.003) -0.113 (0.21) 0.33 (0.447)
Board size -0.002 (0.003) 0.019 (0.186) -0.234 (0.633)
Board average tenure -0.002 (0.001)** 0.043 (0.062) 0.254 (0.147)*
Board meeting per year
-0.003 (0.001)***
-0.097
(0.029)*** -0.219 (0.089)**
Number of independent directors 0.002 (0.003) 0.091 (0.202) 0.812 (0.676)
Number of independent directors in the
audit committee 0.002 (0.002) 0.114 (0.15) 0.038 (0.379)
CEO Duality -0.008 (0.006) 0.081 (0.391) 1.894 (1.124)*
CEO Tenure 0.002 (0.002) 0.142 (0.107) 0.174 (0.276)
CEO Compensation -0.065 (0.031)** -1.277 (1.04) -1.001 (2.678)
Stock owned by CEO 0.006 (0.003)* -0.118 (0.235) -0.485 (0.682)
CEO Age -0.003 (0.002) -0.04 (0.138) -0.24 (0.303)
Female board chairperson 0.009 (0.02) -0.597 (0.947) 0.594 (3.305)
Female CEO -0.042 (0.02)** -0.621 (1.214) -1.334 (2.624)
Industry 0.016 (0.005)*** 0.657 (0.33)** -0.27 (0.832)
43
Number of employees -0.005 (0.003)* 0.551 (0.204)*** 1.861 (0.45)***
Aruoba-Diebold-Scotti Business
Conditions Index 0.016 (0.064) 1.571 (6.654) 5.191 (12.551)
Economic Policy Uncertainty (EPU)
index -0.001 (0.001)** -0.03 (0.041) -0.131 (0.108)
Firm performance measure lag 1 0.71 (0.03)*** 0.421 (0.039)*** 0.387 (0.042)***
Firm performance measure lag 2 0.013 (0.018) 0.018 (0.013) -0.032 (0.013)**
Observations 14896 14896 14896
Sargan Test (df = 346) 360.228 354.56 318.37
AR(1) -13.1291*** -8.933*** -6.340***
AR(2) -1.07636 -0.339 0.805
Table 12
Critical mass of female directors (U.S. sample) This table reports two-step dynamic panel system GMM estimations of the natural log of Tobin’s Q, ROA and ROE
on the number of female directors, number of female directors squared, critical mass 30% dummy, interaction
between critical mass and number of female directors, and control variables. All models include year dummy
variables. All independent variables are treated as endogenous except year dummy variables. Endogenous variables
are instrumented by two of their past values. In parentheses are finite-sample robust standard errors (Windmeijer,
2005). The null hypothesis for the Sargan test of overidentification is that all instruments are exogenous. AR(1) and
AR(2) are test statistics for the null hypothesis that there is no serial correlation of orders 1 and 2 in the first-
difference residuals. *, ** and *** denote statistical significance at 10%, 5% and 1% respectively.
Ln Tobin’s Q ROA ROE
No of female directors -0.016 (0.008)* -0.604 (0.485) -1.964 (1.206)
Percentage of female executives 0.001 (0.001)* -0.006 (0.044) -0.01 (0.15)
Percentage of females in the
workforce 0.001 (0.002) -0.086 (0.125) -0.089 (0.434)
Board size -0.001 (0.003) -0.005 (0.186) -0.098 (0.593)
Board average tenure -0.002 (0.001)** 0.017 (0.059) 0.205 (0.152)
Board meeting per year -0.003 (0.001)*** -0.104 (0.031)*** -0.251 (0.09)***
Number of independent directors 0.002 (0.003) 0.122 (0.197) 0.61 (0.668)
Number of independent directors in
the audit committee 0.003 (0.002) 0.076 (0.15) 0.09 (0.371)
CEO Duality -0.006 (0.006) 0.141 (0.395) 1.555 (1.141)
CEO Tenure 0.001 (0.002) 0.094 (0.09) 0.214 (0.311)
44
CEO Compensation -0.04 (0.023)* -0.902 (0.729) -1.657 (2.188)
Stock owned by CEO 0.005 (0.003)* -0.239 (0.236) -0.667 (0.609)
CEO Age -0.002 (0.002) 0.008 (0.116) -0.172 (0.352)
Female board chairperson 0.004 (0.018) -1.373 (1.253) -1.854 (2.875)
Female CEO -0.03 (0.016)* -0.303 (1.035) -0.684 (2.777)
Industry 0.015 (0.004)*** 0.567 (0.294)* -0.362 (1.28)
Number of employees -0.005 (0.003)** 0.555 (0.193)*** 1.924 (0.555)***
Aruoba-Diebold-Scotti Business
Conditions Index 0.02 (0.056) 3.429 (5.345) -3.965 (13.26)
Economic Policy Uncertainty (EPU)
index -0.001 (0.001)** -0.016 (0.041) -0.127 (0.094)
Critical Mass 30% 0.016 (0.038) 0.956 (2.529) -1.996 (6.434)
No of female directors^2 0.005 (0.002)* 0.195 (0.135) 0.794 (0.382)*
No of female directors * Critical
Mass 30% -0.01 (0.011) -0.327 (0.747) 0.608 (2.017)
Firm performance measure lag 1 0.726 (0.026)*** 0.415 (0.039)*** 0.383 (0.043)***
Firm performance measure lag 2 0.022 (0.017) 0.017 (0.013) -0.034 (0.013)***
Observations 14896
14896 14896
Sargan Test (df = 418) 412.49
438.94 383.88
AR(1) -13.481***
-8.869*** -6.352***
AR(2) -1.291***
-0.346 0.824
Table 13
Critical mass of female directors – Robustness check using percentage of female directors (U.S.
sample) This table reports two-step dynamic panel system GMM estimations of the natural log of Tobin’s Q, ROA and ROE
on the percentage of female directors, percentage of female directors squared, critical mass 30% dummy, interaction
between critical mass and number of female directors, and control variables. All models include year dummy
variables. All independent variables are treated as endogenous except year dummy variables. Endogenous variables
are instrumented by two of their past values. In parentheses are finite-sample robust standard errors (Windmeijer,
2005). The null hypothesis for the Sargan test of overidentification is that all instruments are exogenous. AR(1) and
AR(2) are test statistics for the null hypothesis that there is no serial correlation of orders 1 and 2 in the first-
difference residuals. *, ** and *** denote statistical significance at 10%, 5% and 1% respectively.
Ln Tobin’s Q ROA ROE
Percentage of female directors -0.001 (0.001) -0.044 (0.036) -0.155 (0.088)*
45
Percentage of female executives 0.001 (0.001)* 0.006 (0.045) -0.009 (0.143)
Percentage of females in the
workforce 0.001 (0.002) -0.089 (0.135) -0.067 (0.435)
Board size -0.002 (0.003) -0.026 (0.186) -0.263 (0.597)
Board average tenure -0.002 (0.001)** 0.014 (0.058) 0.21 (0.145)
Board meeting per year -0.003 (0.001)*** -0.101 (0.03)*** -0.243 (0.089)***
Number of independent directors 0.002 (0.003) 0.094 (0.199) 0.584 (0.694)
Number of independent directors in
the audit committee 0.002 (0.002) 0.067 (0.148) 0.062 (0.37)
CEO Duality -0.007 (0.006) 0.101 (0.389) 1.613 (1.142)
CEO Tenure 0.001 (0.002) 0.084 (0.096) 0.179 (0.3)
CEO Compensation -0.041 (0.023)* -0.972 (0.716) -1.828 (2.25)
Stock owned by CEO 0.005 (0.003)* -0.239 (0.23) -0.696 (0.643)
CEO Age -0.001 (0.002) 0.058 (0.124) -0.144 (0.367)
Female board chairperson 0.005 (0.018) -1.048 (1.131) -1.497 (3.01)
Female CEO -0.033 (0.017)** -0.407 (1.045) -0.768 (2.879)
Industry 0.015 (0.004)*** 0.582 (0.291)** -0.316 (1.336)
Number of employees -0.005 (0.003)** 0.528 (0.198)*** 1.908 (0.562)***
Aruoba-Diebold-Scotti Business
Conditions Index 0.031 (0.056) 3.756 (5.063) -1.09 (12.406)
Economic Policy Uncertainty (EPU)
index -0.001 (0.001)* -0.016 (0.041) -0.123 (0.095)
Critical Mass 30% 0.025 (0.036) 1.473 (2.465) -0.399 (6.382)
No of female directors^2 0.003 (0.002)* 0.138 (0.099) 0.662 (0.284)*
No of female directors * Critical
Mass 30% -0.011 (0.011) -0.44 (0.717) 0.259 (1.951)
Firm performance measure lag 1 0.724 (0.026)*** 0.41 (0.039)*** 0.384 (0.043)***
Firm performance measure lag 2 0.023 (0.017) 0.018 (0.013) -0.035 (0.013)***
Observations 14896
14896 14896
Sargan Test (df = 418) 413.44
429.21 387.06
AR(1) -13.437***
-8.864*** -6.370***
46
AR(2) -1.336
-0.374 0.831
Table 14
Relationship between board gender diversity and firm performance (Europe sample)
This table reports two-step dynamic panel system GMM estimations of the natural log of Tobin’s Q, ROA and ROE
on the number of female directors and control variables. All models include year dummy variables. All independent
variables are treated as endogenous except year dummy variables. Endogenous variables are instrumented by two of
their past values. In parentheses are finite-sample robust standard errors (Windmeijer, 2005). The null hypothesis for
the Sargan test of overidentification is that all instruments are exogenous. AR(1) and AR(2) are test statistics for the
null hypothesis that there is no serial correlation of orders 1 and 2 in the first-difference residuals. *, ** and ***
denote statistical significance at 10%, 5% and 1% respectively.
Ln Tobin’s Q ROA ROE
No of female directors 0.001 (0.005) 0.015 (0.262) 1.033 (0.648)
No of female executives 0.002 (0.007) -0.375 (0.282) -0.073 (0.351)
Board size 0 (0.004) -0.252 (0.202) 0.012 (0.344)
Board average tenure -0.006 (0.005) -0.024 (0.171) -0.689 (0.555)
Board average age 0.003 (0.005) -0.202 (0.152) 0.197 (0.234)
Board meeting per year -0.001 (0.002) -0.133 (0.09) -0.11 (0.188)
Number of independent directors -0.01 (0.007) -0.05 (0.218) -0.715 (0.39)*
Number of independent directors in the
audit committee 0.003 (0.006) -0.134 (0.481) 0.688 (0.63)
CEO Duality -0.018 (0.017) 1.407 (0.967) -1.355 (1.997)
Female board chairperson -0.009 (0.04) -1.976 (1.529) -0.522 (3.742)
Female CEO -0.022 (0.035) 1.886 (2.001) -1.153 (2.496)
Industry 0.01 (0.004)** 0.055 (0.164) 0.89 (0.371)**
Number of employees -0.014 (0.012) -0.305 (0.469) -0.367 (0.792)
Economic Policy Uncertainty (EPU)
index -0.002 (0.002) 0.063 (0.122) -0.099 (0.113)
Firm performance measure lag 1 0.612 (0.13)*** 0.497 (0.07)*** 0.783 (0.101)***
Firm performance measure lag 2 0.155 (0.086)* 0.126 (0.057)** 0.032 (0.059)
Observations 745 745 745
Sargan Test (df = 272) 133.99 133.56 130.60
AR(1) -1.274 -3.017*** -2.334**
47
AR(2) 0.863 -1.462 -1.174
Table 15
Critical mass of female directors (Europe sample) This table reports two-step dynamic panel system GMM estimations of the natural log of Tobin’s Q, ROA and ROE
on the number of female directors, number of female directors squared, critical mass 30% dummy, interaction
between critical mass and number of female directors, and control variables. All models include year dummy
variables. All independent variables are treated as endogenous except year dummy variables. Endogenous variables
are instrumented by two of their past values. In parentheses are finite-sample robust standard errors (Windmeijer,
2005). The null hypothesis for the Sargan test of overidentification is that all instruments are exogenous. AR(1) and
AR(2) are test statistics for the null hypothesis that there is no serial correlation of orders 1 and 2 in the first-
difference residuals. *, ** and *** denote statistical significance at 10%, 5% and 1% respectively.
Ln Tobin’s Q ROA ROE
No of female directors -0.012 (0.016) -0.525 (0.715) 2.424 (1.339)*
No of female executives 0.003 (0.007) -0.23 (0.248) -0.227 (0.43)
Board size 0 (0.004) -0.242 (0.202) 0.074 (0.348)
Board average tenure -0.005 (0.005) 0.02 (0.214) -0.872 (0.467)*
Board average age 0.002 (0.004) -0.253 (0.132)* 0.117 (0.234)
Board meeting per year -0.001 (0.002) -0.18 (0.1)* -0.17 (0.176)
Number of independent directors -0.007 (0.007) 0.17 (0.172) -0.515 (0.413)
Number of independent directors in the
audit committee 0.003 (0.006) -0.319 (0.371) 0.208 (0.64)
CEO Duality -0.016 (0.021) 1.082 (0.923) -2.207 (1.92)
Female board chairperson 0.005 (0.043) -1.511 (1.465) 0.025 (4.015)
Female CEO -0.024 (0.04) -0.214 (1.906) -1.142 (2.613)
Industry 0.008 (0.004)** 0.025 (0.142) 0.692 (0.352)**
Number of employees -0.012 (0.01) -0.43 (0.485) 0.14 (0.675)
Economic Policy Uncertainty (EPU)
index -0.001 (0.001) 0.051 (0.124) -0.046 (0.078)
Critical Mass 30% -0.013 (0.063) 2.378 (3.097) -10.93 (6.072)*
No of female directors^2 0.002 (0.003) 0.098 (0.125) -0.501 (0.264)*
No of female directors * Critical Mass
30% -0.002 (0.019) -0.489 (0.785) 3.281 (1.719)*
Firm performance measure lag 1 0.609 (0.134)*** 0.495 (0.069)*** 0.791 (0.101)***
48
Firm performance measure lag 2 0.199 (0.102)* 0.151 (0.058)*** 0.024 (0.064)
Observations 745 745 745
Sargan Test (df = 272) 122.68 131.01 120.75
AR(1) -1.230 -3.012*** -2.377**
AR(2) 0.826 -1.545 -1.218
Table 16
Relationship between board gender diversity and firm performance (Asia sample)
This table reports two-step dynamic panel system GMM estimations of the natural log of Tobin’s Q, ROA and ROE
on the number of female directors and control variables. All models include year dummy variables. All independent
variables are treated as endogenous except year dummy variables. Endogenous variables are instrumented by two of
their past values. In parentheses are finite-sample robust standard errors (Windmeijer, 2005). The null hypothesis for
the Sargan test of overidentification is that all instruments are exogenous. AR(1) and AR(2) are test statistics for the
null hypothesis that there is no serial correlation of orders 1 and 2 in the first-difference residuals. *, ** and ***
denote statistical significance at 10%, 5% and 1% respectively.
Ln Tobin’s Q ROA ROE
No of female directors -0.019 (0.019) -0.541 (1.318) -0.732 (1.768)
No of female executives 0.002 (0.003) 0.003 (0.121) 0.002 (0.111)
Percentage of females in the workforce 0 (0.001) -0.001 (0.034) -0.002 (0.023)
Board size -0.015 (0.014) 0.057 (0.405) 0.089 (0.550)
Board average tenure 0.007 (0.011) -0.506 (0.481) -0.607 (0.682)
Board average age -0.003 (0.005) 0.101 (0.209) 0.011 (0.243)
Board meeting per year -0.002 (0.006) 0.131 (0.301) 0.242 (0.334)
Number of independent directors 0.012 (0.016) -0.957 (0.856) -0.998 (0.766)
Number of independent directors in the
audit committee 0.012 (0.028) 0.13 (1.457) 0.11 (1.950)
CEO Duality -0.04 (0.103) 2.291 (2.125) 1.654 (2.320)
CEO Tenure 0.003 (0.011) 0.85 (0.481)* 1.230 (0.391)*
Female CEO -0.046 (0.107) 1.122 (4.758) 1.164 (4.662)
Stock owned by CEO -0.128 (0.137) -0.297 (2.068) -0.343 (2.583)
Industry 0.058 (0.044) -0.281 (0.902) -0.347 (1.002)
Number of employees 0.011 (0.014) 0.14 (0.541) 0.34 (0.751)
Firm performance measure lag 1 0.763 (0.27)*** 0.386 (0.205)* 0.423 (0.195)*
49
Firm performance measure lag 2 -0.239 (0.303) -0.021 (0.13) -0.034 (0.12)
Observations 328 328 328
Sargan Test (df = 282) 25.73 19.08 21.58
AR(1) -2.140** -1.432 -1.654
AR(2) 0.647 0.646 0.666
Table 17
Critical mass of female directors (Asia sample) This table reports two-step dynamic panel system GMM estimations of the natural log of Tobin’s Q, ROA and ROE
on the number of female directors, number of female directors squared, critical mass 30% dummy, interaction
between critical mass and number of female directors, and control variables. All models include year dummy
variables. All independent variables are treated as endogenous except year dummy variables. Endogenous variables
are instrumented by two of their past values. In parentheses are finite-sample robust standard errors (Windmeijer,
2005). The null hypothesis for the Sargan test of overidentification is that all instruments are exogenous. AR(1) and
AR(2) are test statistics for the null hypothesis that there is no serial correlation of orders 1 and 2 in the first-
difference residuals. *, ** and *** denote statistical significance at 10%, 5% and 1% respectively.
Ln Tobin’s Q ROA ROE
No of female directors 0.021 (0.069) -1.665 (3.507) -1.785 (2.907)
No of female executives -0.003 (0.003) 0.158 (0.168) 0.177 (0.155)
Percentage of females in the workforce 0 (0.002) 0.076 (0.037)** 0.033 (0.069)*
Board size -0.006 (0.012) 0.442 (0.52) 0.67 (0.51)
Board average tenure 0 (0.011) 0.019 (0.488) 0.009 (0.631)
Board average age -0.009 (0.005)** 0.075 (0.21) 0.066 (0.29)
Board meeting per year -0.008 (0.007) 0.475 (0.255)* 0.498 (0.335)*
Number of independent directors 0.005 (0.017) -0.595 (0.965) -0.239 (0.810)
Number of independent directors in the
audit committee 0.026 (0.033) 0.41 (1.335) 0.56 (1.081)
CEO Duality 0.007 (0.119) 2.441 (2.287) 1.987 (1.287)
CEO Tenure 0.013 (0.013) 0.993 (0.49)** 0.873 (0.449)*
Female CEO 0.152 (0.129) 6.027 (5.456) 5.821 (3.483)
Stock owned by CEO 0.081 (0.12) 0.829 (1.651) 0.962 (1.551)
Industry 0.01 (0.042) 0.334 (1.131) 0.291 (0.978)
Number of employees -0.008 (0.013) 0.431 (0.674) 0.503 (0.874)
50
Critical Mass 30% -0.498 (0.391) -8.937 (37.674) -7.342 (28.591)
No of female directors^2 -0.012 (0.015) 0.029 (1.082) 0.011 (1.140)
No of female directors * Critical Mass
30% 0.14 (0.114) 3.692 (10.558) 2.687 (9.328)
Firm performance measure lag 1 0.514 (0.264)* 0.493 (0.247)** 0.454 (0.337)**
Firm performance measure lag 2 -0.027 (0.328) 0.094 (0.109) 0.088 (0.124)
Observations 328 328 328
Sargan Test (df = 313) 21.65 15.73 16.54
AR(1) -1.996** -1.483 -1.663*
AR(2) 0.066 -0.339 -0.322