I'm having trouble using the constant term in lincom following an ANOVA.
Here's what I've done:
#delimit ;
anova y
subj|group group tmcond method
group*tmcond group*method tmcond*method
group*tmcond*method;
...ANOVA Output produced...
lincom _cons+_coef[group[1]]+_coef[tmcond[1]]+_coef[method[1]]
+_coef[group[1]*tmcond[1]]+_coef[group[1]*method[1]]
+_coef[tmcond[1]*method[1]]+_coef[group[1]*tmcond[1]*method[1]];
invalid syntax
r(198);
It seemed that lincom could not reference the constant term _cons, so I
tried another tack by explicitly fitting the constant:
gen const = 1
#delimit ;
anova y
const subj|group group tmcond method
group*tmcond group*method tmcond*method
group*tmcond*method, noconstant;
...ANOVA Output produced...
lincom _coef[const]+_coef[group[1]]+_coef[tmcond[1]]+_coef[method[1]]
+_coef[group[1]*tmcond[1]]+_coef[group[1]*method[1]]
+_coef[tmcond[1]*method[1]]+_coef[group[1]*tmcond[1]*method[1]];
_b[const] not found
r(111);
In either case I can't use the constant term in lincomp. Any suggestions are
welcome. I'm looking for the model estimate of the mean and its se for the
group==1, method==1, tmcond==1 cell of the design.
Thank you,
Richard Steiner
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