prediction of future ratings of companies, those are rated by broker firms
DESCRIPTION
None of the attributes are perfectly correlated, even it is rare in life but out of these three attributes, range of offerings is highly correlated to ratings. Where as the ease of use has weak relation of only 0.42 with star rating. Trade execution which is important quality of the broker firm has 0.746 correlations. Correlation of rating and ranges is 0.827.TRANSCRIPT
http://stochasticanalytic.com/research/
PREDICTION OF FUTURE RATINGS OF COMPANIES, THOSE ARE RATED BY BROKER FIRMS
Fig: 1 Fig: 2
Fig: 3 In these three figures the linearity relationship between the
Star rating and independent variables are shown. Based on
the observations the relationship between star rating and
range of offerings is strong, where as the relation between the
rating and ease of use is very low. Linearity relationship
varies from -1 to +1. None of the relationship is perfectly
positive but rating and range has 0.827, which is highest
among them.
5.04.03.02.01.0
TradeEx
4.0
3.5
3.0
2.5
2.0
Rat
ing
R Sq Linear = 0.556
4.54.03.53.02.5
Ease
4.0
3.5
3.0
2.5
2.0
Rat
ing
R Sq Linear = 0.176
5.04.54.03.53.02.5
Range
4.0
3.5
3.0
2.5
2.0
Rat
ing
R Sq Linear = 0.685
In the above figures of scatter plot between the rating and other variables are interesting because the range of offerings in figure 3 shows better relationship and again it is noticeable that all the variables are positively correlated to the ratings.
Correlations
1 .746* .420 .827**.013 .227 .003
10 10 10 10.746* 1 .229 .434.013 .524 .210
10 10 10 10.420 .229 1 .301.227 .524 .397
10 10 10 10.827** .434 .301 1.003 .210 .397
10 10 10 10
Pearson CorrelationSig. (2-tailed)NPearson CorrelationSig. (2-tailed)NPearson CorrelationSig. (2-tailed)NPearson CorrelationSig. (2-tailed)N
Rating
TradeEx
Ease
Range
Rating TradeEx Ease Range
Correlation is significant at the 0.05 level (2-tailed).*.
Correlation is significant at the 0.01 level (2-tailed).**.
5.04.54.03.53.02.5
Range
4.0
3.5
3.0
2.5
2.0
Rat
ing
R Sq Linear = 0.685
5.04.54.03.53.02.5
Range
4.0
3.5
3.0
2.5
2.0
Rat
ing
R Sq Cubic =0.85
If rating and range is linearly related then the R 2 value is 0.685, which is increased to 0.85 by considering the relationship as cubic. Hence the transformation of value of rating and range can improve the relationship. Transforming the value of range the relationship increases from 0.685 to 0.762. Even transforming the value of rating and range both the relationship goes stronger to 0.767. Correlation between rating and range is 0.827 which improves after transformation to 0.873 between rating and inverse of range and to 0.876 between squire of rating and inverse of range.
0.300.280.260.240.220.200.180.16
invRn
4.0
3.5
3.0
2.5
2.0
Rat
ing
R Sq Linear = 0.762
0.300.280.260.240.220.200.180.16
invRn
16.00
14.00
12.00
10.00
8.00
6.00
4.00
sqRt
R Sq Linear = 0.767
Model 1: Star rating = 0.864+0.647*Range of offeringsModel 2: Star rating = 6.393 -14.376/ (1+Range of offerings)
Model 3: (Star rating) 2 = 29.651 -86.045/ (1+Range of offerings)Any one may follow the model 2 because model 1 can not relate star rating to the range of offerings. In model 1, if the range of offerings is 4 then rating will be 3.452, where as model 2 can rate 3.518. But with further improvement through transformation can help to build up model 3. Model3 can rate 3.527 for range of offerings of 4. This improvement is possible because of the improvement in correlation between the rating and range.
Model Summary b
.876a .767 .738 1.79269 1.779Model1
R R SquareAdjustedR Square
Std. Error ofthe Estimate
Durbin-Watson
Predictors: (Constant), invRna.
Dependent Variable: sqRtb.
ANOVAb
84.640 1 84.640 26.337 .001a
25.710 8 3.214110.350 9
RegressionResidualTotal
Model1
Sum ofSquares df Mean Square F Sig.
Predictors: (Constant), invRna.
Dependent Variable: sqRtb.
Coefficients a
29.659 3.766 7.874 .000-86.045 16.767 -.876 -5.132 .001 1.000 1.000
(Constant)invRn
Model1
B Std. Error
UnstandardizedCoefficients
Beta
StandardizedCoefficients
t Sig. Tolerance VIFCollinearity Statistics
Dependent Variable: sqRta.
Regressing the Star rating with the independent variables like Trade execution, Ease of use and range of offering this model could be build. Based on the observations on 10 brokers’s this regression model can be developed for predicting the Star rating in the nest year.
210-1-2
Regression Standardized Predicted Value
4.0
3.5
3.0
2.5
2.0
Rating
Dependent Variable: Rating
Scatterplot
R Sq Linear = 0.886
Star rating = 0.345 + 0.255*(Trade Execution) + 0.132*(Ease of use) + 0.459*(Range of offerings)
Correlations
1.000 .746 .420 .827.746 1.000 .229 .434.420 .229 1.000 .301.827 .434 .301 1.000
. .007 .114 .002.007 . .262 .105.114 .262 . .199.002 .105 .199 .
10 10 10 1010 10 10 1010 10 10 1010 10 10 10
RatingTradeExEaseRangeRatingTradeExEaseRangeRatingTradeExEaseRange
Pearson Correlation
Sig. (1-tailed)
N
Rating TradeEx Ease Range
Star rating is positively related to ratings for trade execution, ease of use and range of offerings. Out of these three qualities, range of offerings is highly correlated to Star ratings (0.827 and statistically significant in 95% confidence) where as the ease of use is insignificant in correlation with star rating and these are reflected in the model also.
Model Summary b
.941a .886 .828 .2431 1.923Model1
R R SquareAdjustedR Square
Std. Error ofthe Estimate
Durbin-Watson
Predictors: (Constant), Range, Ease, TradeExa.
Dependent Variable: Ratingb.
Higher value of R2 (0.886) of this model signifies the goodness of fit or the sample regression line is fitting well with the observations on 10 broker platform.
ANOVAb
2.745 3 .915 15.485 .003a
.355 6 .0593.100 9
RegressionResidualTotal
Model1
Sum ofSquares df Mean Square F Sig.
Predictors: (Constant), Range, Ease, TradeExa.
Dependent Variable: Ratingb.
In this model the explained sum squire (ESS) is 2.745 and residual sum of squire is 0.355 which is the reason for goodness of fit. Here R2 is equal to ESS/TSS and TSS=ESS+RSS, TSS is total sum squire. Analysis of variance or ANOVA is useful for testing the significance of the model as Star rating has three independent variables. In the f-test for this model the degree of freedom for numerator is 3 because it has three independent variables and denominator has 10 – four variables = 6, degree of freedom. Hence from the f table it could be found the standard value is 4.76. But the model has 15.485 of f-test value which is in the critical or significance zone with p value of 0.003. As the p value is less than 0.05, hence the whole model is significant. But if the model is looked in to detail that the easy of use has insignificant correlation with the Star rating as well as the p value of t-test is lower than the 0.05. Hence the null hypothesis of assumption that the coefficients are equal and zero can be rejected.
Coefficients a
.345 .531 .650 .540
.255 .086 .460 2.978 .025 .801 1.249
.132 .140 .138 .944 .382 .897 1.114
.459 .123 .586 3.722 .010 .768 1.302
(Constant)TradeExEaseRange
Model1
B Std. Error
UnstandardizedCoefficients
Beta
StandardizedCoefficients
t Sig. Tolerance VIFCollinearity Statistics
Dependent Variable: Ratinga.
Three independent variables have standard t value of 1.943 at the 6 degree of freedom. In this model trade execution and range of offerings have t-test value of 2.978 and 3.722, which is higher than the 1.943 or p value is lower than 0.05. Hence for these two variables the hypothesis of considering the coefficient with zero value can be rejected. Star rating = 0.345 + 0.255*(Trade Execution) + 0.132*(Ease of use) + 0.459*(Range of offerings)
In this model if the trade execution drops by -2 then the effect on star rating will be – (0.255*2) = -0.51. Or the star rating will be decreased by 0.51. Where as the decrease in range of offerings by -3 will impact on Star rating by 0.459*3= 1.377. Or the star rating will be decreased by 1.337. Change in range of offerings will be impacted more for this model.
This regression model has fewer diseases (Low Multicollinerity as VIF is nearly 1, no auto regression as DW is nearly 2) but can be improved by Increasing the sample sizeInclusion of more variablesTransforming variables.Transforming all four variables it can be observed that the correlation is significantly improved.
Correlations
1.000 .746 .420 .827.746 1.000 .229 .434.420 .229 1.000 .301.827 .434 .301 1.000
. .007 .114 .002.007 . .262 .105.114 .262 . .199.002 .105 .199 .
10 10 10 1010 10 10 1010 10 10 1010 10 10 10
RatingTradeExEaseRangeRatingTradeExEaseRangeRatingTradeExEaseRange
Pearson Correlation
Sig. (1-tailed)
N
Rating TradeEx Ease Range
Correlations
1.000 -.876 .813 .505-.876 1.000 -.636 -.288.813 -.636 1.000 .149.505 -.288 .149 1.000
. .000 .002 .068.000 . .024 .210.002 .024 . .341.068 .210 .341 .
10 10 10 1010 10 10 1010 10 10 1010 10 10 10
sqRtinvRninvTrsqEsqRtinvRninvTrsqEsqRtinvRninvTrsqE
Pearson Correlation
Sig. (1-tailed)
N
sqRt invRn invTr sqE
210-1-2
Regression Standardized Predicted Value
16.00
14.00
12.00
10.00
8.00
6.00
4.00
sqRt
Dependent Variable: sqRt
Scatterplot
R Sq Linear = 0.956
In this model the R2 value or goodness of fit is now increased to 0.956. And all the three variables are significant from t-test.
Coefficients a
24.261 2.399 10.112 .000-49.867 11.312 -.508 -4.408 .005 .558 1.793-20.291 5.063 -.447 -4.008 .007 .595 1.681
.242 .074 .292 3.253 .017 .915 1.093
(Constant)invRninvTrsqE
Model1
B Std. Error
UnstandardizedCoefficients
Beta
StandardizedCoefficients
t Sig. Tolerance VIFCollinearity Statistics
Dependent Variable: sqRta.
(Star rating) 2 = 24.261 -20.291/ (1+Trade Execution) + 0.242(Ease of use) 2 -49.867/ (1+Range of offerings) This improved model is built up by transforming the variables and excluding the other possibilities of improvement a model.