Chapter 5 Results
5.11 Confirmatory Factor Analysis
5.11.5 Multigroup analysis
In the previous sections on CFA and path analysis, the models were analysed with respect to a single group. This study also extends the analysis to determine if the model was equivalent for, or
applicable to two groups. The groups used in the analysis were different genders (Males and Females) and different years-of-study (First and Third Year students).
Tests for measurement invariance were performed to assess if the models demonstrated invariance across the different gender groups and the different years-of-study groups. Tests for the structural invariance were performed to assess if the individual paths in a structural model were equivalent across different gender groups and the different years-of-study groups, or if the path coefficients varied between groups (Meyers et al., 2013). Both of the tests for the measurement invariance and structural invariance were conducted using IBM SPSSAMOS.
5.11.5.1 Testing for measurement invariance across groups
According to Meyers et al. (2013), testing for measurement invariance across groups should be assessed by a Chi-square difference test that compares two different models. The two models are:
The unconstrained model - where the groups yielded different values of the parameters (a Chi- square value was derived by computing model fit for the pooled sample of all groups).
The constrained model - where certain parameters were constrained to be equal between the groups (a Chi-square value was yielded for the constrained model).
A Chi-square difference test was used to determine if there was a significant difference between the fit measures for the two models. If the Chi-square difference test was not statistically significant between the unconstrained and the constrained models, then the model was invariant across groups and showed group equivalence. Therefore, the same model is applicable to both groups (Meyers et al., 2013).
5.11.5.1.1 Testing for measurement invariance across First Year students and Third Year students
This section details the test to determine if the SEM model is applicable across groups (for First Year students as well as Third Year students) and if the factor structure provides group equivalence.
Figure 5-26 The Unconstrained Model for Different Years-of-study Groups
Table 5-75 Goodness-of-Fit Statistics for the Unconstrained Model for Different Years-of-study Groups
Goodness-of Fit Indices
Values
Chi-Square (π³π³
2)
669.430
Degree of Freedom (df)
358
Normed Chi-square (π³π³
2/df)
1.870
Comparative Fit Index (CFI)
Normed Fit Index (NFI)
Tucker-Lewis Index (TLI)
Root Mean Square Error of Approximation (RMSEA)
0.955
0.909
0.947
0.049
Table 5-75 reveals the π³π³2 value is 669.43 with 358 degrees of freedom. The Normed Chi-square, CFI,
NFI, TLI and RMSEA values are: 1.870, 0.955, 0.909, 0.947 and 0.049, respectively.All model fit indices sufficiently satisfy the relative recommended thresholds (Byrne, 2010; Hair et al., 2010). Therefore, the unconstrained model fit is adequate between First and Third Year students.
Figure 5-27 The Constrained Model for Different Years-of-study Groups
Table 5-76 Goodness-of-Fit Statistics for the Constrained Model for Different Years-of-study Groups
Goodness-of Fit Indices
Values
Chi-Square (π³π³
2)
700.314
Degree of Freedom (df)
379
Normed Chi-square (π³π³
2/df)
1.848
Comparative Fit Index (CFI)
Normed Fit Index (NFI)
Tucker-Lewis Index (TLI)
Root Mean Square Error of Approximation (RMSEA)
0.954
0.905
0.949
0.048
Table 5-76 reveals the π³π³2 value is 700.314 with 379 degrees of freedom. The Normed Chi-square,
CFI, NFI, TLI and RMSEA values are: 1.848, 0.954, 0.905, 0.949 and 0.048, respectively. All model fit indices sufficiently satisfy the relative recommended thresholds (Byrne, 2010; Hair et al., 2010). Therefore, the constrained model is adequate between First and Third Year students.
Table 5-77 The Chi-square Difference Test Results
Chi-square
df
P_val
Overall Model
Unconstrained
669.43
358
Fully constrained
700.314
379
Number of groups
2
Difference
30.884
21
0.076
Since P = 0.076 > 0.05, there is no significant difference between the fit measures for the
unconstrained model and the constrained model. Therefore, the model is invariant across the First and Third Year students.
5.11.5.1.2 Testing for measurement invariance across Males and Females
This section details the test to determine if the same SEM model is applicable across groups (for Males as well as Females) and if the factor structure provides group equivalence. The same
unconstrained and constrained model (see Figure 5-26 and 5-27) were used to test for measurement invariance across different genders groups.
Table 5-78 Goodness-of-Fit Statistics for the Unconstrained Model for Different Genders Groups
Goodness-of Fit Indices
Values
Chi-Square (π³π³
2)
668.739
Degree of Freedom (df)
358
Normed Chi-square (π³π³
2/df)
1.868
Comparative Fit Index (CFI)
Normed Fit Index (NFI)
Tucker-Lewis Index (TLI)
Root Mean Square Error of Approximation (RMSEA)
0.955
0.909
0.947
0.049
Table 5-78 reveals the π³π³2 value is 668.739 with 358 degrees of freedom. The Normed Chi-square,
CFI, NFI, TLI and RMSEA values are: 1.868, 0.955, 0.909, 0.947 and 0.049, respectively. All model fit indices sufficiently satisfy the relative recommended thresholds (Byrne, 2010; Hair et al., 2010). Therefore, the unconstrained model is adequate betweenMales and Females.
Table 5-79 Goodness-of-Fit Statistics for the Constrained Model for Different Genders Groups
Goodness-of Fit Indices
Values
Chi-Square (π³π³
2)
687.515
Degree of Freedom (df)
379
Normed Chi-square (π³π³
2/df)
1.814
Comparative Fit Index (CFI)
Normed Fit Index (NFI)
Tucker-Lewis Index (TLI)
Root Mean Square Error of Approximation (RMSEA)
0.955
0.906
0.950
0.047
Table 5-79 reveals the π³π³2 value is 687.515 with 379 degrees of freedom. The Normed Chi-square,
CFI, NFI, TLI and RMSEA values are: 1.814, 0.955, 0.906, 0.950 and 0.047, respectively. All model fit indices sufficiently satisfy the relative recommended thresholds (Byrne, 2010; Hair et al., 2010). Therefore, the constrained model is adequate between Males and Females.
Table 5-80 The Chi-square Difference Test Results
Chi-square
df
P_val
Overall Model
Unconstrained
668.739
358
Fully constrained
687.515
379
Number of groups
2
Difference
18.776
21
0.600
Since P = 0.600 > 0.05, there is no significant difference between the fit measures for the
unconstrained model and the constrained model. The model is invariant across Males and Females.
5.11.5.2 Testing for structural invariance across groups (Path Analysis)
With measurement invariance established, structural invariance was then tested in order to determine if the causal relationships exist between the groups, or if the path coefficients vary between the groups (Meyers et al., 2013).
IBM SPSS AMOS compares the groups in five different ways in the default setup, including structural weights, structural intercepts, structural means, structural covariances, and structural residuals. This study focused on only one of the comparisons β structural weights, which refer to the path
coefficients (Meyers et al., 2013). The analysis was performed to evaluate the difference between the unconstrained model and the constrained model. Model differences were evaluated with a Chi- square test. The two models being compared were:
The constrained model β where the groups yielded equivalent values of the parameters (Meyers et al., 2013). If the Chi-square test was not statistically significant, then there was no significant difference in fit between the unconstrained and the constrained models as measured across the groups.
5.11.5.2.1 Testing for structural invariance across First Year students and Third Year students
This section presents the results of test to determine if the causal relationships are present between the two groups (First and Third Year students), or if the path coefficients vary between the groups.
Figure 5-28 The Unconstrained Model for Different Years-of-study Groups
Table 5-81 Goodness-of-Fit Statistics for the Unconstrained Model for Different Years-of-study Groups
Goodness-of Fit Indices
Values
Chi-Square (π³π³
2)
669.430
Degree of Freedom (df)
358
Normed Chi-square (π³π³
2/ππππ)
1.870
Comparative Fit Index (CFI)
Normed Fit Index (NFI)
Tucker-Lewis Index (TLI)
Root Mean Square Error of Approximation (RMSEA)
0.955
0.909
0.947
0.049
Table 5-81 reveals the π³π³2 value is 669.430 with 358 degrees of freedom. The Normed Chi-square,
indices sufficiently satisfy the relative recommended thresholds (Byrne, 2010; Hair et al., 2010). Therefore, the unconstrained model is adequate between First and Third Year students.
Figure 5-29 The Constrained Model for Different Years-of-study Groups
Table 5-82 Goodness-of-Fit Statistics for the Constrained Model for Different Years-of-study Groups
Goodness-of Fit Indices
Values
Chi-Square (π³π³
2)
677.965
Degree of Freedom (df)
368
Normed Chi-square (π³π³
2/ππππ)
1.842
Comparative Fit Index (CFI)
Normed Fit Index (NFI)
Tucker-Lewis Index (TLI)
Root Mean Square Error of Approximation (RMSEA)
0.955
0.908
0.949
0.048
Table 5-82 reveals the π³π³2 value is 677.965 with 368 degrees of freedom. The Normed Chi-square,
CFI, NFI, TLI and RMSEA values are: 1.842, 0.955, 0.909, 0.949 and 0.048, respectively. All model fit indices sufficiently satisfy the relative recommended thresholds (Byrne, 2010; Hair et al., 2010). Therefore, the constrained model is adequate between First and Third Year students.
Model Comparison
For the comparison involving the path coefficients, labelled as Structural weights in Table 5-83, the Chi-square value is 8.535, with 10 degrees of freedom (there are ten paths in the model), the P value is 0.577. Since P = 0.577 > 0.05, there is no significant difference in fit between the unconstrained and the constrained models as measured across First and Third Year students.
Table 5-83 The comparison of the unconstrained and constrained models
Assuming model Unconstrained to be correct:
Model
DF CMIN P
NFI Delta-1
IFI Delta-2
RFI rho-1
TLI rho2
Structural weights 10 8.535 .577 .001
.001
-.002 -.002
Table 5-84 The comparisons of the ten paths in the modelFirst Year
Third Year
Estimate
P
Estimate
P
z-stat
SI <--- SQ
0.504
0.000
0.576
0.000
0.636
UI <--- SQ
0.535
0.000
0.443
0.000
-0.982
UI <--- SI
0.219
0.010
0.409
0.000
1.737*
SS <--- SQ
0.329
0.000
0.196
0.006
-1.148
SS <---
SI
0.038
0.675
0.071
0.334
0.285
SS <--- UI
0.611
0.000
0.598
0.000
-0.082
SL <--- SQ
0.051
0.616
0.100
0.198
0.388
SL <--- SS
0.278
0.016
0.386
0.000
0.686
SL <--- UI
0.739
0.000
0.563
0.000
-0.860
SL <---
SI
-0.029
0.762
-0.159
0.051
-1.029
Notes: *** p-value < 0.01; ** p-value < 0.05; * p-value < 0.10
Table 5-84 shows that in terms of the individual paths, the only group difference is observed for the path from Student Involvement to University Image between First Year students and Third Year students (z = 1.737, p < 0.10). The path coefficients from Student Involvement to University Image are 0.409 and 0.219 for Third Year students and First Year students, respectively. The results illustrate that the Third Year students who perceive a high level of student involvement are more likely to have a good image of the university than the First Year students. No group difference is observed for the other nine paths in the model between First Year students and Third Year students.
5.11.5.2.2 Testing for structural invariance across Males and Females
This section presents the results of test to determine if the causal relationships are present between the two groups (Males and Females), or if the path coefficients vary between the groups. The same
unconstrained and constrained model as Figure 5-28 and 5-29 were used to test for structural invariance across different gender groups.
Table 5-85 Goodness-of-Fit Statistics for the Unconstrained Model for Different Genders Groups
Goodness-of Fit Indices
Values
Chi-Square (π³π³
2)
668.739
Degree of Freedom (df)
358
Normed Chi-square (π³π³
2/ππππ)
1.868
Comparative Fit Index (CFI)
Normed Fit Index (NFI)
Tucker-Lewis Index (TLI)
Root Mean Square Error of Approximation (RMSEA)
0.955
0.909
0.947
0.049
Table 5-85 reveals the π³π³2 value is 668.739 with 358 degrees of freedom. The Normed Chi-square,
CFI, NFI, TLI and RMSEA values are: 1.868, 0.955, 0.909, 0.947 and 0.049, respectively. All model fit indices sufficiently satisfy the relative recommended thresholds (Byrne, 2010; Hair et al., 2010). Therefore, the unconstrained model is adequate between Males and Females.
Table 5-86 Goodness-of-Fit Statistics for the Constrained Model for Different Genders Groups
Goodness-of Fit Indices
Values
Chi-Square (π³π³
2)
676.939
Degree of Freedom (df)
368
Normed Chi-square (π³π³
2/ππππ)
1.868
Comparative Fit Index (CFI)
Normed Fit Index (NFI)
Tucker-Lewis Index (TLI)
Root Mean Square Error of Approximation (RMSEA)
0.955
0.909
0.947
0.049
Table 5-86 reveals the π³π³2 value is 676.939 with 368 degrees of freedom. The Normed Chi-square,
CFI, NFI, TLI and RMSEA valuesare: 1.868, 0.955, 0.909, 0.947 and 0.049, respectively. All model fit indices sufficiently satisfy the relative recommended thresholds (Byrne, 2010; Hair et al., 2010). Therefore, the constrained model is adequate between Males and Females.
Model Comparison
For the comparison involving the path coefficients, labelled as Structural weights in Table 5-87, the Chi-square value is 8.200, with 10 degrees of freedom (there are ten paths in the model), the P value is 0.609. Since P = 0.609 > 0.05, there is no significant difference in fit between the unconstrained and the constrained models as measured across Males and Females.
Table 5-87 The comparison of the unconstrained and constrained models
Assuming model Unconstrained to be correct:
NFI
Delta-1
Delta-2 IFI
rho-1 RFI
rho2 TLI
Model DF CMIN P
Structural Invariance 10 8.200 .609
.001
.001 -.002 -.002
Table 5-88 The comparisons of the ten paths in the model
Male Female
Estimate P Estimate P z-stat 0.511 0.000 0.542 0.000 0.273 0.513 0.000 0.446 0.000 -0.706 0.218 0.002 0.453 0.000 2.023** 0.213 0.005 0.305 0.000 0.818 0.062 0.345 0.058 0.558 -0.030 0.598 0.000 0.610 0.000 0.075 0.182 0.070 0.054 0.493 -1.000 0.313 0.045 0.333 0.000 0.110 0.577 0.000 0.607 0.000 0.144
SI <--- SQ
UI <--- SQ
UI <--- SI
SS <--- SQ
SS <--- SI
SS <--- UI
SL <--- SQ
SL <--- SS
SL <--- UI
SL <--- SI
-0.113 0.188 -0.060 0.512 0.423Notes: *** p-value < 0.01; ** p-value < 0.05; * p-value < 0.10
Table 5-88 shows that in terms of the individual paths, the only group difference is observed for the path from Student Involvement to University image between Males and Females (z = 2.023, p < 0.05). The path coefficients from Student Involvement to University Image are 0.453 and 0.218 for Females and Males, respectively. The results illustrate that Females who perceive a high level of student involvement are more likely to have a good image of the university than Males. No group difference is present for the other nine paths in the model between Males and Females.
Table 5-89 Summary of Hypotheses Testing
Hypotheses Result
H1: There is a significant positive relationship between the Interaction Quality primary dimension and studentsβ overall service quality perceptions.
Supported, Interaction Quality has a significant impact on overall service quality perceptions.
H2: There is a significant positive relationship between the Physical Environment Quality primary dimension and studentsβ overall service quality perceptions.
Supported, Physical Environment Quality has a significant impact on overall service quality perceptions.
H3: There is a significant positive relationship between the Outcome Quality primary dimension and studentsβ overall service quality perceptions.
Supported, Outcome Quality has a significant impact on overall service quality perceptions.
H4: There is a significant positive relationship between the Social Factors Quality primary dimension and studentsβ overall service quality perceptions.
Supported, Social Factors Quality has a significant impact on overall service quality perceptions.
H5: Students will vary in their perceptions of the
importance of each of the primary dimensions. Supported,importance of the primary dimensions follows Outcome Quality is the most by Social Factors Quality, Interaction Quality, and Physical Environment Quality.
H6: Higher perceptions of Service Quality
positively affect Student Satisfaction. Supported,and direct impact on Student Satisfaction. Service Quality has a significant H7: Higher perceptions of Service Quality
positively affect University Image. Supported,and direct impact on University Image. Service Quality has a significant H8: Higher perceptions of Service Quality
positively affect Student Involvement. Supported,and direct impact on Student Involvement. Service Quality has a significant H9: Higher perceptions of Service Quality
positively affect Student Loyalty. Not Supported, have a significant and direct impact on Service Quality does not Student Loyalty, but it has indirect effect through Student Satisfaction.
H10: Student Satisfaction mediates the relationship between Service Quality and Student Loyalty.
Supported, Student Satisfaction partial mediates the relationship between Service Quality and Student Loyalty.
H11: Higher University Image positively
affects Student Satisfaction. Supported,significant and direct impact on Student University Image has a Satisfaction.
H12: Higher University Image positively
affects Student Loyalty. Supported,significant and direct impact on Student University Image has a Loyalty.
H13: Higher Student Involvement positively
affects Student Satisfaction. Not Supported, not have a significant and direct impact on Student Involvement does Student Satisfaction.
H14: Higher Student Involvement positively
affects University Image. Supported,significant and direct impact on University Student Involvement has a Image.
H15: Higher Student Involvement positively
affects Student Loyalty. Not Supported, not have a significant and direct impact on Student Involvement does Student Loyalty.
H16: Student Involvement mediates the relationship between Service Quality and Student Satisfaction.
Supported, Student Involvement partial mediates the relationship between Service Quality and Student Satisfaction.
H17: Student Involvement mediates the relationship between Service Quality and University Image.
Supported, Student Involvement partial mediates the relationship between Service Quality and University Image.
H18: Higher Student Satisfaction positively
affects Student Loyalty. Supported,significant and direct impact on Student Student Satisfaction has a Loyalty.
H19: Student perceptions relating to interrelationships among Service Quality, Student Satisfaction, Student Involvement, University Image, and Student Loyalty will differ between the First Year and Third Year students.
Partial Supported, the only group difference is observed for the path from Student
Involvement to University Image between First and Third Year students.
H20: Student perceptions relating to interrelationships among Service Quality, Student Satisfaction, Student Involvement, University Image, and Student Loyalty will differ between Males and Females.
Partial Supported, the only group difference is observed for the path from Student
Involvement to University Image between Males and Females.