ALIAS procedure

Finds out information about aliased model terms in analysis of variance (R.W. Payne).


Options

TREATMENTSTRUCTURE = formula
Treatment model for the design

BLOCKSTRUCTURE = formula
Block model for the design

FACTORIAL = scalar
Value used in the FACTORIAL option of ANOVA if not the default

DESIGN = pointer
Design structure for the analysis


Parameter

TERM = factors
Factors defining the aliased model term


Description

When a term is aliased in an analysis of variance, it is listed in the Information summary (produced by ANOVA [PRINT=information]) under the heading "Aliased model terms" (see the Guide to GenStat, Part 2, Section 4.7.1). However ANOVA does not indicate the terms with which it is aliased. This information can be obtained using procedure ALIAS.

   The aliased term is specified by setting the TERM parameter to the list of factors that define it. The structure of the design can be specified either by options BLOCKSTRUCTURE and TREATMENTSTRUCTURE (together with option FACTORIAL, if necessary); alternatively you can save the design structure from the original analysis and supply this using the DESIGN option - this is the only way of specifying the design if there are weights or if the analysis is restricted. If an undeclared structure is specified for DESIGN (and BLOCKSTRUCTURE and TREATMENTSTRUCTURE are also specified), it will be set to the design structure for the analysis.


Options: TREATMENTSTRUCTURE, BLOCKSTRUCTURE, FACTORIAL, DESIGN.

Parameter: TERM.


Method

The procedure calculates a set of dummy effects for the aliased model term, and then forms and analyses a variate in which only these effects are present. The analysis detects the model terms to which the term is aliased as those that have non-zero sums of squares.


Action with RESTRICT

None of the options nor parameters are vectors. To indicate that the analysis is of a restricted set of units you must use the DESIGN option to specify the design structure from the original analysis.