st: Stuck in a logistic regression. Roadmap

[Pedro Merino García <pmerino2@gmail.com>]

Dear Statalist,

I am just arrived to Stata in the last month. Even thought I find it easier and more flexible than my previous software for standard statistics, I am stuck performing a logistic regression because I find the style is very different from SPSS.  I would like to ask you some questions:
	
1) In the selecting variables phase, I performed lrtest of constant model and the model with the variable I try to test. If the number of observations are different the lrtest is not valid. What method do you recommend in this case?

2)I used SPSS where I did backstep logistic regression based on the LR. Can I perform this kind of analysis in Stata? Is the stepwise a recommended method to perform this kind of regression?

3) I used a macro called AllSetsReg in SPSS, in which I could obtain the best subsets based on Cp Mallows and AIC. I know there are some packages to do that in Stata, but I have more than 6 variables. Do you know any package or method to do that?

4) I am follow the Hosmer-Lemeshow way of performing the regression, but I don´t know if that´s the best way to do it. Is there a better way to perform a log regression? Do you have any suggestion or any roadmap to model which works for you.

Thank you very much.

Regards.


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