design perceptions group – university of ulster drs common ground conference & exhibition the...

DRS Common Ground Conference & Exhibition

Design Perceptions Group – University of Ulster

The development of empirical techniques for the investigation of design

perception

Quantifying the

Unquantifiable ?

ABSTRACT

This project proposes a scientific approach to the investigation of design perception in order to develop concepts, theories and techniques for improving the effectiveness of design. This research shows that participant-based perception experiments can be used to support intuitive understanding of design by allowing formal hypothesis to be formulated and tested under scientific conditions. This study then, seeks to build on our intuitive knowing and ensure the effective mapping of design intent onto consumer perception by investigating the nature of consumer interpretation.



CONTENTSAbstract

Aims

Introduction

Why Assess Design Character?

How can Design Character be Measured?

General Method

Experimental Protocols

Experiment 1

Sample Stimulus Set

Experiment 2

Making Sense of the Data

Experiment 1 Hypothesis

Discussion of Results

Experiment 2Hypothesis

Discussion of Results

Determinants of Product Character

Opportunities for Design Practitioners

Gender Perception in Product Design

The Role of Prototypicality in Design

Practical Implications

Anecdotal Evidence

Significant Findings

Further Study

Comments

About the Authors

References



INTRODUCTIONAccording to Klaus Krippendorff, design is the creation of meaning as well as the creation of a physical artefact. If so, then designers must look beyond the visual and investigate how designed artefacts are interpreted by the intended audience. As Theodore Levitt put it, "The purpose of a product is not what the engineer explicitly says it is, but what the consumer implicitly demands that it shall be.“ This would suggest the need to develop an empirical method for assessing perceptual response to design – a sort of ‘perceptual ergonomics’ to complement intuitive knowledge. This is not to say that intuition has not been successful - it has guided product development since Neanderthal man fashioned the first crude axe - or that scientific enquiry is inherently superior, just that intuitive ability varies from person-to-person and as such can be unreliable.

“The purpose of a product is not what the engineer explicitly

says it is but what the consumer implicitly demands that it shall

be.”

Intuitive ability varies from person-to-person and as

such can be unreliable. This would suggest the need to

develop an empirical method for assessing perceptual

response to design – a sort of ‘perceptual ergonomics’

to complement intuitive knowledge



AIMS & OBJECTIVES

Develop empirical techniques to quantitatively assess the perception of design character

Show that participant-based experiments can be used to complement traditional intuitive methods.

Improve communication in design by investigating how consumers interpret design character and exploring what factors affect product perception

Improve the effectiveness of design though better understanding of consumer interpretation of design character



Which products appear most robust?

IMAGE CREDIT: Argos Catalogue Spring 2002

“Facing the intense changes in the market, a well-designed product should not only satisfy consumers’ physical requirements but should also satisfy their psychological needs.” (Hsiao and Chen, 1997)

Only by understanding how shape and form affect perceived character can the designer hope to satisfy not just physical requirements but emotional and psychological requirements. It has long been recognised that shape and form can be used to communicate the perception of ‘elegance’, ‘durability’ or ‘ease-of-use’. Designers have always tried to exploit the connection between visual appearance and perceived character (Janlert, 1997). For instance, many small domestic products e.g. power tools attempt to communicate the perception of robustness through design. It could even be argued that perception is more important than reality, for few would buy a chair which looked fragile regardless of the actual strength or durability of the product. Physical strength is not enough, the perception of strength must be communicated though design. Consider the two exercise cycles shown here, although the cycle on the right may look more robust but both products actually have the same maximum load strength of 100kg

WHY ASSESS DESIGN CHARACTER?

WHY?



A ‘LUXURIOUS’ CHAIR

HOW CAN DESIGN CHARACTER BE MEASURED? The study of product semantics assumes that shapes certain shapes evoke certain emotions and associations in the eye of the beholder (Hsiao and Chen, 1997; Janlert, 1997). By systematically manipulating the shape of different products and assessing the corresponding change in perceived character it may be possible to better understand how design affects consumer interpretation.

But is it possible to ‘measure’ the perception of design character?

People regularly talk of products as having character as a means of understanding and describing them (Janlert, 1997) and it is not unusual for people to use adjectival image words to describe the feelings engendered by an object. Someone might describe the chairs (shown left) as ‘luxurious’ or ‘modern’. Given that people are accustomed to evaluating products in this way there is no reason why participant groups could not be asked to assess perceived character on the basis of pre-defined keywords.

A ‘MODERN’ CHAIR

People often use adjective image words to describe their

perception of a object or product. It is not unreasonable then to use pre-defined keywords as a means of assessing perceived character

IMAGE CREDIT: Argos Catalogue Spring 2002



Participants were exposed to a set of images and asked to evaluate them on the basis of pre-defined keywords

Product variables were systematically manipulated to explore the affect of

specific design changes on design character

PRODUCT DESIGN RESEARCH STUDY

SECTION A

THANK YOU FOR YOUR CONTRIBUTION

SECTION B

INSTRUCTIONSPERSONAL INFORMATION INSTRUCTIONS

A

E

I

B C

GF

D

L

H

J K

ROBUST

GENERAL METHOD

Each study is based on a convenience sample of undergraduate students drawn from a range of courses in the Faculties of Engineering and Arts at the University of Ulster.

IMAGE CREDIT: Shane Crothers



EXPERIMENTAL PROTOCOLSParticipants received both verbal and written instructions on the task to be undertaken and were instructed to determine which design is most representative, moderately representative and least representative of each keyword. The keywords were not printed on the response sheet so that evaluation would reflect the perceived character of the product rather than previous responses. Also, keywords were strategically presented to avoid the introduction of systematic bias i.e. terms with obvious associations such as, ‘masculine’ and ‘feminine’ were not presented sequentially. Keywords were presented, using the same size and type of font (Arial) and because exposure time was not considered to be of critical importance no limit was imposed on response time.

Participants received both verbal and written instructions on the task

and were instructed to determine which design is most

representative, moderately representative and least

representative of each keyword.PRODUCT DESIGN RESEARCH STUDY

SECTION A

By the School of Electrical & Mechanical Engineering and the School of Design & Communication

THANK YOU FOR YOUR CONTRIBUTION

All personal information will be treated as confidential

NAME

AGE

GENDER

COURSE

LEAST

MOST

SECTION B

LEAST

MOST

You will be shown a range of kettles and then asked to rank order these kettles

based on the descriptive terms shown on the overhead. Please record your

response to each term in the appropriate column.

There is no right or wrong answer and responses will not be graded.

PERSONAL INFORMATION INSTRUCTIONS




EXPERIMENTAL OBJECTIVES

The study consisted of two experiments. The same procedures, sample group and keywords were used in both experiments; only the stimulus set changed. Experiment 1 investigated the affect of changes in form on the perception of design character while Experiment 2 investigated the affect of the addition of graphic elements on perceived character. Unfortunately, there are many aspects of product appearance such as colour, surface highlights and reflections that may affect the perception of design character. So in both experiments the kettles were presented as black and white silhouettes.

There are many aspects of product appearance such as colour, surface

highlights and reflections that may

affect the perception of design character. So in

both experiments the kettles were presented

as black and white silhouettes.

A

E

I

B C

GF

D

L

H

J K




EXPERIMENT 1

In Experiment 1 participants were exposed to a set of 12 black and white kettle silhouettes derived from 3 ‘primary’ types designated ‘Alpha’, ‘Beta’ and ‘Gamma’. It should be noted that these primary silhouettes were based on 3 actual products. Modifications were then made to the spout, handle and base of each ‘primary’ type in order to generate the set of 12 i.e. each primary silhouette was complemented by 3 variations.

Modifications were made to the spout, handle and base of each ‘primary’ type in

order to generate the stimulus set

PRIMARY HANDLE

BODY SPOUT

ALPHA

BETA

GAMMA




SAMPLE STIMULUS SET

These images were then arranged so that no two variations of each ‘primary’ kettle type

were positioned adjacent to each other.


A

E

I

B C

GF

D

L

H

J K



KA

KE

KB

KF KG

KC

KH

KD

EXPERIMENT 2

In Experiment 2 the shape/form did not change but graphic elements were added to the side of the kettle. It is reasonable to assume that any change in perceived character would be attributable to the addition of these graphic elements. A new set of 8 kettles (see below) designated KA through KH was used as the stimulus and again design character was assessed using pre-defined keywords.





MAKING SENSE OF THE DATA

Evidence supporting the formal hypothesis is provided in a number of ways:

• Comments by the participants often provide useful insight into the evaluative process.

• Data is examined in order to identify agreement (consensus) on how design modifications affect the perception of design character. • Correlation coefficients are calculated using the Spearman Method. • Chi Squared values (written as 2) are computed which describe the degree of mismatch between expected values and observed values.



EXPERIMENT 1 – HYPOTHESES

The objective of this first experiment is to provide evidence that changes in form influence the perception of design. This intention is captured in these formal hypotheses.

Ho: Changes in form do not alter the perceived character of a product

H1: Changes in form do alter the perceived character of a product

STATISTICAL REASONING If the null hypothesis Ho is correct and changes in form do not alter perceived character then there is an equal probability of each kettle being seen as representative of a given keyword. That is, each kettle has an equal chance of being considered representative of a given keyword.

BUT………

If there is not an equal distribution this would suggest that Ho is false and changes in form do alter the perceived character of the product (suppH1). By calculating Chi Squared values (written as 2) it is possible to quantify the deviation from the expected equal distribution and assess the significance of this deviation. Essentially then, the 2 statistic measures the degree of disagreement or mismatch between the data and the null hypothesis. The further the observed responses (O) are from the expected value (E) greater the mismatch and the larger 2 will become. Therefore, large values of 2 imply that Ho is false and that changes in form do alter perceived character.



EXPERIMENT 1

DISCUSSION OF RESULTS The results indicate that, for this experiment, the null hypothesis is invalid. The Observed values (O) do not equal the expected values (E) suggesting that Ho is false and that changes in form do alter the character of a product. Furthermore, all of the computed 2 values (summarised left) achieved significance at the a = 0.1 level or better. It is on this basis that we reject the null hypothesis and assert that changes in form do alter perceived character.

Kettle

Ranking

Most Moderate Least

2 2 2

A 115 0.005 10 -- 107 0.005

B 33 0.005 8 -- 17 0.1

C 34 0.005 14 -- 33 0.005

D 127 0.005 9 -- 44 0.005

E 53 0.005 24 0.025 36 0.005

F 70 0.005 29 0.005 109 0.005

G 296 0.005 42 0.005 90 0.005

H 31 0.005 11 -- 111 0.005

I 71 0.005 15 -- 16 --

J 30 0.005 22 0.05 21 0.05

K 37 0.005 13 -- 25 0.025

L 23 0.005 23 0.025 34 0.005

Table 1: Experiment 1 - 2 values for each kettle suggesting that Ho is false

[1] Veryzer, R., W., Hutchinson, J., W., (1998), The influence of unity and prototypicality on aesthetic responses to new product designs, Journal of Consumer Research, Vol.24, March[2] McClave, J., T., Sincich, T., Statistics, London, Prentice-Hall, 2000



EXPERIMENT 2 – HYPOTHESES

The objective of this second experiment is to provide evidence that the addition of graphic elements affects the perception of design character. This is captured in these formal hypotheses.

Ho: The addition of graphic elements does not alter perceived characterH1: The addition of graphic elements does affect the perceived character of a product.

STATISTICAL REASONING The statistical reasoning used here is exactly the same as in Experiment 1. If the null hypothesis Ho is correct and changes and the addition of graphic elements does not alter perceived character then there is an equal probability of each kettle being seen as representative of a given keyword.

BUT………

If there is not an equal distribution this would suggest that Ho is false and changes in form do alter the perceived character of the product (i.e. supporting H1). Again, it is possible to quantify the deviation from the expected equal distribution and assess the significance of this deviation using the Chi Squared method. So as before, 2 statistic measures the degree of disagreement or mismatch between the data and the null hypothesis. Again, large values of C2 imply that Ho is false. In this case suggesting that the addition of graphic elements does affect perceived character.



Kettle

Ranking

Most Moderate Least

2 2 2

KA 41 0.005 16 0.1 30 0.005

KB 293 0.005 17 0.1 26 0.005

KC 62 0.005 31 0.005 677 0.005

KD 125 0.005 88 0.005 7.3 --

KE 13 0.1 131 0.005 81 0.005

KF 124 0.005 67 0.005 50 0.005

KG 58 0.005 21 0.025 35 0.005

KH 134 0.005 11 -- 176 0.005 Table 5: Experiment 2 - 2 values for each kettle suggesting that Ho is false

[1] The statistical reasoning used to test the formal hypothesis is the same as in Experiment 1

EXPERIMENT 2

DISCUSSION OF RESULTS Observed values (O) do not equal the expected values (E) suggesting that Ho is

false and that the addition of features does affect product perception. Again, Chi Squared values describing the degree of mismatch between the expected mean and the observed values were calculated for each kettle. Most of these values (summarised left) achieved significance at the = 0.1 level or better suggesting that Ho is false. It is on this basis that we

reject the null hypothesis and assert that the addition of graphic elements does affect product perceived character (H1).



The evidence suggests that the character of a kettle is affected more

by modification of the handle than modification of the body or the spout.

DETERMINANTS OF DESIGN CHARACTERUpon examination of the results, it is interesting to note the difference between the Chi Squared values for each primary type and the modified silhouettes.

For each ‘primary’ type there would appear to be a large difference between Chi Squared values for unmodified primary silhouette and silhouettes with modified handles. Also, for each ‘primary’ kettle type there is only a small difference between Chi Squared values for silhouettes with modifications to the body and the spout. Significantly, this suggests that the character of a kettle is affected more by modification of the handle than modification of the body or the spout.

2 = 115 ( = .005) 2 = 37 ( = .005) 2 = 70 ( = 0.005) 2 = 70 ( = .005)

2 = 127 ( = .005) 2 = 33 ( = .005) 2 = 31 ( = 0.005) 2 = 30 ( = .005)

2 = 296 ( = .005) 2 = 34 ( = .005) 2 = 53 ( = .005) 2 = 30 ( = .005)

PRIMARY HANDLE BODY SPOUT

MODIFIED SILHOUETTES

What are the practical implications? IMAGE CREDIT: Shane Crothers



OPPORTUNITIES FOR DESIGN PRACTITIONERS Visual re-styling is often used as a means of prolonging the product life cycle. This practice is particularly common with mature products - the automobile being a notable example (see below). But these ‘facelifts’ cost money in terms of design, re-tooling, etc. so clearly the goal would be to cause the greatest (positive) impact on consumer perception as the result of the minimum number of design changes. This research suggests that product character may be affected more by the modification of certain design elements. Using this empirical method to assess perceived character it may be possible to determine which design elements most strongly affect product perception and focus creative effort on those features thereby improving the effectiveness of design.

This could help improve design effectiveness by focusing creative effort on those features which

significantly affect product perception

Product character may be affected more by the modification of certain

design elements

IMAGE CREDIT: www.autotrader.co.uk



GENDER PERCEPTION IN PRODUCT DESIGN

Design is often used to communicate gender and there are many examples of products may be functionally identical but are designed with a masculine or feminine appearance, a good example being the Remington electric razor (shown right). But what exactly constitutes a ‘masculine’ design and what constitutes a ‘feminine’ design? This research provides experimental evidence which suggests that certain shapes are considered to be masculine while others are considered feminine. Specifically, there is evidence which suggests that graphic elements incorporating straight lines are considered masculine, while graphic elements incorporating curves and circles are considered feminine.

IMAGE CREDIT: Argos Catalogue Spring 2002What exactly constitutes a ‘masculine’ design

and what constitutes a ‘feminine’ design?

Which of these

products is masculine

and which is feminine?

WHY?



PROTOTYPICALITY IN DESIGN This research indicates that perceived prototypicality might have a positive affect on the formulation of preference in product design. That is, consumers prefer products that they perceive to be most representative of a given product type or category. Furthermore there is evidence to suggest that these representations are not just visual constructs they also carry gender associations and meaning.

WHAT IS A ‘PROTOTYPE’?

The concept of prototypicality originated in computational cognitive psychology. Essentially prototypes are mental constructs that facilitate object recognition and can best be described as an, “idealised internalised representation” (Guenther, 1998). In this context term ‘prototype’ describes a product which is considered to be representative of a given product category or set. The term should not be confused the more familiar interpretation as being: a visualisation or physical model of a product concept. It should be also be noted that a prototype does not necessarily correspond to any physical object, it is an abstraction, a composite of many examples of a given object.

BUT HOW CAN THIS BENEFIT

DESIGN PRACTICE?



PRACTICAL IMPLICATIONSThe notion that prototypical (familiar) products may preferred over atypical (novel designs) is not alien to product design. Conventional wisdom states that new products are adopted more rapidly if they are compatible with existing values, product knowledge and past experience. This principle is often exploited in design. Early automobiles were designed to look like horse drawn carriages they replaced, 50’s television sets were designed to look like furniture, even early computers bore more than a passing resemblance with the more familiar typewriter (above right). Many new products have failed largely because they deviated too far from the consumer’s prototypical preconceptions. In the 30’s the Chrysler Airflow (right) flopped because it was considered too radical yet the VW (right) designed in 1937 by Ferdinand Porsche incorporated much of the style and technological innovation of the Airflow. Successful design is often a balance between the excitement derived from innovation and the reassurance derived from familiarity. This duality is reflected in Raymond Loews's MAYA formula: ‘Most Advanced Yet Acceptable’.

“Most Advanced Yet Acceptable.”

Successful design is often a balance between the

excitement derived from innovation and the

reassurance derived from familiarity

IMAGE CREDIT: www.webshots.comIMAGE CREDIT: Penny Sparke, Design for the 20th Century

Use of this method to assess perceived prototypicality affords the opportunity to explore prototypical preconceptions and provides a means positioning a new product so that it is perceived to be innovative but not excessively radical.



ANECDOTAL EVIDENCE Comments by the participants provide useful insight into the evaluative process. Overheard comments suggest that, while consensus and general agreement with respect to perceived character certainly exists, it is impossible insulate evaluation of design from subjective influences. For instance, kettle E (shown right) was considered to be feminine by some because it looked ‘pregnant’ and masculine by others because it looked as if it had a ‘beer belly’. This kind of comment illustrates that evaluation may make reference to the social and cultural context. One mechanism for this being the use of analogy. It also demonstrates that verbal language is often inadequate when describing the physical and semantic properties of a design. Therefore people often seek to describe design through the use of an analogy which describes the both shape and the character of the object. The Ford KA (right) was once described as, “an egg with Grace Jones haircut”. The comment that kettle E had a ‘beer belly’ was an attempt to describe, not just the shape but also the character (in this case the perceived gender) of the product. Such comments represent useful qualitative evidence that shape affects design character.

Comments by the participants provide useful insight into the evaluative

process This kettle was

considered to be feminine by some because it looked

‘pregnant’ and masculine by others

because it looked as if it had a ‘beer

belly’

People often seek to describe design through the use of an analogy which describes the both shape and character of the object.

IMAGE CREDIT: Shane CrothersIMAGE CREDIT: www.autotrader.co.uk

The Ford KA was once described as, “an egg with Grace Jones haircut”



SIGNIFICANT FINDINGS To date, this research shows that:

• Empirical methods can be used to assess the perception of design character

• Quantitative techniques can be used to test formal hypothesis about design perception.

• Design changes, such as changes in form and the addition of features, affect the perceived character of a product

• Product perception may be affected more by the modification of certain design elements.

• Certain shapes are considered to be masculine and others feminine.

• Perceived prototypicality might have a positive affect on the formulation of preference in product design.

BUT MOST IMPORTANTLY…….



MOST IMPORTANTLY……

This research demonstrates how participant-based testing can be used to complement traditional intuitive understanding of how design is interpreted by the consumer.

AND

Systematically manipulating product variables and quantitatively assessing the perception of design character represents a scientific means of investigating design perception.



Does the visual context affect the perception of this

Mercades?

FURTHER STUDY To investigate the affect of visual context and presentation format on the perception of product character. Using this method it should be possible to assess the affect of visual context and presentation format (2D, 3D and physical model) on perceived character. Given that effective concept ‘screening’ requires accurate feedback from the consumer it is important that the concept is presented in an appropriate manner which is likely to yield an realistic response.

IMAGE CREDIT: www.webshots.com



FURTHER STUDY Intuition tells us that visual context affects product perception (just compare the two Mercades shown below). This principle is often used in advertising where a product is presented in carefully chosen context. A sports car may be presented in a highly dynamic, exciting context; as with the Golf GTI (shown left). The hope being that the product will be associated with the positive attributes of the surroundings. Consider the new VW Beetle (shown below left) which is presented in a fun, fairground context beside the original Beetle. Essentially, advertisers are trying to forge - or to borrow a term from information theory - encode conceptual relationships between the visual context and product.

Using this method it should be possible to assess the affect of visual context and presentation format (2D, 3D and physical model) on perceived character. Given that effective concept ‘screening’ requires accurate feedback from the consumer it is important that the concept is presented in an appropriate manner which is likely to yield an realistic response.


Products are often presented in carefully chosen context so that the product will

be associated with the positive attributes of the surroundings

A sports car may be presented in a highly

dynamic, exciting context; as with this

Golf GTI.

Here the new VW Beetle is presented in a fun, fairground context beside the original Beetle….advertisers are trying to forge - or to borrow a term from information theory - encode conceptual relationships between the visual context and product.




COMMENTS

Significantly, this research demonstrates how participant-based testing can be used to complement traditional intuitive methods in design. It has been shown that quantitative methods can be used to explore consumer perception of design character and that these methods could help improve design effectiveness in a practical context.

If you have any comments or suggestions for the authors please contact as

your input would be greatly appreciated and valued



ABOUT THE AUTHORS

Shane Crothers BSc (Hons) is a Research Associate in the School of Electrical and Mechanical Engineering at the University of Ulster. He is currently using an empirical method for assessing design character to conduct an investigation into design perception.

Dr. Robin Clarke BSc DPhil CEng MIMechE FIED is the Head of the School of Electrical and Mechanical Engineering and has research interests in product design/development and engineering design education.

Dr Ian Montgomery BA DPhil MCSD MSTDEd FRSA is Lecturer in Graphic Design and is Course Director for BA(Hons) Visual Communication in the School of Art & Design. He has research interests in design management and the appropriateness of design.

EXHIBITION COMPLIED BY:

The ‘Design Perceptions Group’ at University of Ulster

The ‘Design Perceptions Group’ is composed of researchers, academics and students with a common interest in studying design perception. If you are interested in this research and wish to know more please feel free to contact:

Shane Crothers, Research Associate

School of Electrical & Mechanical Engineering

University of Ulster, Newtownabbey

Northern Ireland, BT37 0QB

Telephone: 028 9036 8636

Fax: 028 9036 6804

Email: [email protected]



REFERENCES

Dahl, D., W., Chattopadhyay, A., Gorn, G., J., (1999), The use of visual mental imagery in new product design, Journal of Marketing Research, Vol.36, No.1

Guenther, R., K., Human Cognition, London, Prentice Hall, 1998

Hsiao, S-W., Chen, C-H., (1997), A semantic and shape grammar based approach for product design, Design Studies, Vol.18, No.3

Janlert, L., E., (1997), The character of things, Design Studies, Vol.18, No.3

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