# st: [Fwd: Comparing dummy categories � logistic]

 From "J. Jabs" <[email protected]> To [email protected] Subject st: [Fwd: Comparing dummy categories � logistic] Date Tue, 20 Sep 2005 16:22:19 -0400 (EDT)

```I have 2 questions at this point:
1. How do I find the effect between dummy categories from logistic
regression? (I will also have this issue when I use �regress� with a
subset of the data (those with tp=1 then the outcome becomes min. in food
prep as a continuous variable).  I was looking at the �adjust� command but
I�m not sure it will do what I want in logistic (or that I understand it)

There are numerous predictors with interactions so I�ll just include a few
to illustrate the point:
xi3: logistic tp age i.agekid partner i.hrwork agekid*partner
i.prhrwork*partner

tp=outcome of time in food preparation (0=none; 1=any)
age is continuous
i.agekid has 4 levels (age youngest kid: 0 =kid 0-4yr; 1= kid 5-12yr; 2=
kid 13-17yr; 4=no kids)
i.prhrwork has 5 levels (hours partner work: 0=full time; 1=part-time;
2=vary; 3=not work; 4=no partner)
partner is categorical (0=no partner; 1=partner)

I understand how to compare the levels to the reference category (ie: for
i.agekid for categories from 0 to 1 or 0 to 2 ), but how do I compare
between groups (ie: for i.agekid for categories from 1 to 2; 2-3; 1-3)?

2.  Is there a way to account for those without partners? For example in
the interaction i.prhrwork I can compare differences in partner work time
as compared to full time, but it does not seem that the comparison of 0 to
4 (partner works full time to no partner) is logical?  I have this issue
for numerous variables that have interactions besides the one described
(no kids vs. age youngest; vs. # kids).
The statistics people here do not have an answer so does anyone have
suggestions?  I'm sure that other people have dealt with this?
I�ve searched online and stata archives, though haven�t located anything
of help. Any assistance would be appreciated.

Regards, Jennifer
[email protected]
(I addressed this to wrong email so sorry if it gets cross posted)

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