SPSS® 12.0 Command Syntax Reference

VARCOMP 1641
CORB Correlation matrix. The asymptotic correlation matrix of the variance
component estimates. One variable is created for each variance component.
(filename) Output filename. Specify one valid filename. The variance component estimates
and the asymptotic covariance or correlation matrix (if requested) are
written to the same file.
DESIGN Subcommand
The DESIGN subcommand specifies the effects in a model. DESIGN can be specified anywhere
after the variable list. If more than one DESIGN subcommand is specified, only the last
one is in effect.
• Specify a list of effect terms to be included in the design. Each term must be separated
from the next by a comma or a space. Valid specifications include the keyword
INTERCEPT, factors, covariates, and interaction or nested terms.
• The factors and covariates must have been specified on the variable list.
• If a factor is specified on the RANDOM subcommand, all effects that include that factor
are random effects.
• If the DESIGN subcommand is omitted or specified without any term, the default design
is generated. The default design includes the intercept term (if INTERCEPT=EXCLUDE is
not specified), the covariates (if any) in the order in which they are specified on the variable
list, the main factorial effects, and all orders of factor-by-factor interaction.
INTERCEPT Include the intercept term. Specifying INTERCEPT on DESIGN explicitly includes
the intercept term regardless of the specification on the INTERCEPT
subcommand.
BY Interaction. You can also use the asterisk (*). Interaction terms can be formed
among factors, among covariates, and between factors and covariates.
Factors inside an interaction effect must be distinct. For factors A, B, and C,
expressions like A*C*A or A*A are invalid.
Covariates inside an interaction effect do not have to be distinct. For covariate
X, X*X is the product of X and itself. This is equivalent to a covariate
whose values are the square of those of X.
WITHIN Nesting. You can also use a pair of parentheses. Factors and covariates can
be nested within factors but no effects can be nested within covariates. Suppose
that A and B are factors and X and Y are covariates. Both A(B) and X(B)
are valid, but X(Y) is not.
Factors inside a nested effect must be distinct. Expressions like A(A) are
invalid.
Multiple-level nesting is supported. For example, A(B(C)) or A WITHIN B
WITHIN C means that factor B is nested within factor C, and factor A is nested
within B(C). The expression A(B)(C) is invalid.