GLM
GLM DEPENDENT_VARS BY FIXED_FACTORS
[/METHOD = SSTYPE(TYPE)]
[/DESIGN = INTERACTION_0 [INTERACTION_1 [... INTERACTION_N]]]
[/INTERCEPT = {INCLUDE|EXCLUDE}]
[/MISSING = {INCLUDE|EXCLUDE}]
The GLM
procedure can be used for fixed effects factorial Anova.
The DEPENDENT_VARS
are the variables to be analysed. You may analyse
several variables in the same command in which case they should all
appear before the BY
keyword.
The FIXED_FACTORS
list must be one or more categorical variables.
Normally it does not make sense to enter a scalar variable in the
FIXED_FACTORS
and doing so may cause PSPP to do a lot of unnecessary
processing.
The METHOD
subcommand is used to change the method for producing
the sums of squares. Available values of TYPE
are 1, 2 and 3. The
default is type 3.
You may specify a custom design using the DESIGN
subcommand. The
design comprises a list of interactions where each interaction is a list
of variables separated by a *
. For example the command
GLM subject BY sex age_group race
/DESIGN = age_group sex group age_group*sex age_group*race
specifies the model
subject = age_group + sex + race + age_group×sex + age_group×race
If no DESIGN
subcommand is specified, then the
default is all possible combinations of the fixed factors. That is to
say
GLM subject BY sex age_group race
implies the model
subject = age_group + sex + race + age_group×sex + age_group×race + sex×race + age_group×sex×race
The MISSING
subcommand determines the handling of missing variables.
If INCLUDE
is set then, for the purposes of GLM analysis, only
system-missing values are considered to be missing; user-missing
values are not regarded as missing. If EXCLUDE
is set, which is the
default, then user-missing values are considered to be missing as well
as system-missing values. A case for which any dependent variable or
any factor variable has a missing value is excluded from the analysis.