Table 5.4 Preliminary Data Analysis- Product Quality Concern (PQC)
Step One - Exploratory
Wording EFA
Loadings
PQC1 PQC2 PQC3
PQC4 PQC5
Difficult to be assured that the product will
perform as well as it is supposed to
.86 PQC1
1.00
Difficult to be assured that the product is
reliable
.91 PQC2
.782
1.00
Worried that the product received cannot
represent accurately
.93
PQC3
.725 .825 1.00
Worried that the performance of the
product cannot live up to what is promised
.92
PQC4
.703 .772 .852 1.00
Worried that the quality of the product
.88
PQC5 .680
.710
.756
.822
1.00
Reliability
0.94
KMO
.874
Variance Explained
81.07
Bartlett’s
.000
Step Two – Confirmatory
Indicators CFA
Stand. Loadings
Stand.
Error
Critical
Ratio
AVE CR
PQC1 .81
--
--
.75
.937
PQC2 .80
.033
32.80
*
PQC3 .89
.040
31.15
*
PQC4 .96
.045
32.17
*
PQC5 .85
.043
29.62
*
Model Fit
Statistic
Model Fit
Statistic
χ
2
1.452
TLI
.996
df
1
CFI
.996
P .228
RMSEA
.022
GFI .995
RMR
.010
*
p
< .001
5.5.4 Preliminary Analysis – Site Design
Eight items (DES1 to DES8) were used to measure the site design
construct. The two-step
preliminary data analysis process shown in Figure 5.1 was employed as a screening
mechanism for data measured by these items (refer Table 5.5 for results). Evaluation of the
correlation matrix through the KMO and Bartlett’s Test results in a high KMO statistic (.901)
and a significant probability level (p< .001) for the Bartlett’s test. These results indicate that
sufficient correlations were found within the correlation matrix for factor analysis to proceed.
In addition, bivariate correlations were inspected and all coefficients fell within the
acceptable range for factor analysis of .30 and .90. EFA was then conducted which produced
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a single factor structure with strong item loading ranging from .78 to .85 and the variance
explained was 69.08%. Cronbach’s alpha of .94 indicated good reliability of the scale. At
this point, as all the items met the criteria of Step One, they were retained for CFA analysis in
Step Two.
In Step Two (refer Figure 5.1), CFA was conducted on the eight items retained from Step
One. The model fit indices indicated that this measurement model poorly fitted the data (
χ
2
/df
= 46.23 > 5, GFI = .787 < .90, TLI = .799 < .90, CFI = .857 < .90, RMSEA = .217 < .08, and
RMR =.143 > .05). After the initial model assessment, the model was modified according to
the modification indices to improve model fit (Hair et al., 1995). Indicators which were
related to larger reductions of chi-square were identified and eliminated one by one. After
deleting item DES2 and DES7, an acceptable model was achieved. For example,
χ
2
/df (1.382)
was less than 5, GFI (.998), TLI (.999) and CFI (0.998) were above .90, RMSEA (.020) was
less than .08 and RMR (.015) was less than .05. The results indicated that the modified
measurement model can be assessed as being adequate, and suggested that the modified
model fitted the data better than the initial model. As displayed in Table 5.5, the standardized
factor loadings of the remaining six items ranged from .77 to .81. All exceeded the ideal
criterion of .70 (Hair
et al.
2006). The AVE for this construct was .64, exceeding the
recommended level of .50 (Hair
et al.
2006). The CR was .914, exceeding the recommended
criterion of .70 (Nunnally 1978). As a result, items DES1, DES3, DES4, DES5, DES6, and
DES8 were considered to provide a reliable and valid measurement scale for site design.
Moreover, these six items were retained for the overall measurement model.
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