The #2 test is interpreted as the test of the
difference between the hypothesized model and the
just identified version of the model. Low, nonsignificant
values are desired.35 However, the #2
test is very sensitive to sample size; thus, in a model
with a relatively large sample size, the null hypothesis
will almost always be rejected. Because of
this limitation, the #2 test was used only to evaluate
the relative differences in fit among competing
models. Incremental fit indexes indicate the proportion
of improvement of the hypothesized model
relative to a null model, typically one assuming no
correlation among observed variables. The generally
agreed upon critical value for the CFI and IFI is
.90 or higher.32,33 The RMSEA is the standardized
summary of the average covariance residuals and is
thus a measure of the lack of fit between the data
and the model. Low values (between 0 and .06)
indicate a good fitting model