st: Re: ## Interaction syntax

[Robin Jeffries <rjeffries@ucla.edu>]

It was indeed a simple missing data problem. Thank you for the responses.

-Robin



On Tue, Jan 11, 2011 at 3:28 PM, Robin Jeffries <rjeffries@ucla.edu> wrote:
> I was under the impression that for a categorical variable 'wave' with
> 3 levels (0, 1, 2)
> and another binary indicator variable 'group' (0,1) then the following
> statements are the same:
>
>
> 1) xtlogit i.wave##i.group (other covar)
>
> 2) xtlogit wave1 wave2 group wg1 wg2 (other covar)
>
> where wave1, wave2, wg1, wg2 are the manually created indicators and
> interactions for wave and wave*group respsectivly
>
>
> For most outcomes I am using this with, they produce the exact same
> results. However there have been some instances where using the second
> method results in a model that won't converge, but the first will.
>
> Is there an explanation for this?
>
> Thanks,
> Robin Jeffries
>
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