Re: st: some questions regarding stcox

[Maarten buis <maartenbuis@yahoo.co.uk>]

--- On Thu, 3/6/10, XU Moqi wrote:
> 1) what do the dots mean which I get instead of standard
> errors in stcox? I get a coefficient but everything else
> is a "."

It means that your model hasn't converged, try to simplify
your model.
 
> 2) how do I compare the fit of 2 models?

You can use -test- after the larger model, if the models 
are nested.

> 3) can I use lagged variables when my analysis time is the
> real time or do I need to correct for anything when doing so?

I don't see a problem

> 4) how can I instrument one of the independent variables?

I don't think you can.

Hope this helps,
Maarten

--------------------------
Maarten L. Buis
Institut fuer Soziologie
Universitaet Tuebingen
Wilhelmstrasse 36
72074 Tuebingen
Germany

http://www.maartenbuis.nl
--------------------------


      

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