Why
didn't Amos report sample moments and residual moments?
When your dataset contains missing values, Amos does not
report sample moments (i.e., sample means, covariances
and correlations) or residual moments.
Sample moments are not reported because there is not a
single agreed-upon way to compute them when the dataset
contains
missing values. Amos could calculate sample moments
using listwise deletion or pairwise deletion, or after
some form of data imputation. Each one of these methods
of taking missing values into account would yield a
different set of "sample moments". In fact, when missing
values are present, Amos does not fit the model to
sample moments at all. Instead, the model is fitted to
the raw data. Sample moments are never computed.
Residual covariances are defined as the difference
between the sample covariances and the model-implied
covariances. Residual covariances cannot be calculated
because sample covariances are not calculated.
Similarly, residual means cannot be calculated because
sample means are not calculated.
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