Message-ID: <20170613182554.D49724057F@losangelesyouthorchestra.org>
Date: 2017-06-13T18:25:54Z
From: Don Cohen
Subject: understanding I() in lmer formula
Is there a difference between I(x*y) and I(y*x) ?
I have a call to lmer that results in this complaint:
Error in is.alpha2.subordinate * ~z.min.co.res :
non-numeric argument to binary operator
when I change this line:
I(is.alpha2.subordinate*z.min.co.res)+
to this:
I(z.min.co.res*is.alpha2.subordinate)+
the complaint goes away.
I'd like to understand why.