User Guide

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Chapter 18
Standard Error of Kurtosis. The ratio of kurtosis to its standard error can be used as a
test of normality (that is, you can reject normality if the ratio is less than -2 or greater
than +2). A l
arge positive value for kurtosis indicates that the tails of the distribution
are longer than those of a normal distribution; a negative value for kurtosis indicates
shorter tails (becoming like those of a box-shaped uniform distribution).
Standard Er
ror of Skewness.
The ratio of skewness to its standard error can be used
as a test of normality (that is, you can reject normality if the ratio is less than -2 or
greater than +2). A large positive value for skewness indicates a long right tail; an
extreme ne
gative value, a long left tail.
Sum. The sum or total of the values, across all cases with nonmissing values.
Variance. A measure of dispersion around the mean, equal to the sum of squared
deviation
s from the mean divided by one less than the number of cases. The variance
is measured in units that are the square of those of the variable itself.
Statisti
cs for First Layer
ANOVA tab
le and eta.
Displays a one-way analysis-of-variance table and calculates
eta and eta squared (measures of association) for each independent variable in the
first layer.
Test for l
inearity.
Calculates the sum of squares, degrees of freedom, and mean square
associated with linear and nonlinear components, as well as the F ratio, R and R
squared. Linearity is not calculated if the independent variable is a short string.