R help - May 2006 - [Re: Running a likelihood ratio test for a logit model]

?glm and have a look at the components of the list returned by the 
object (i.e. glm.mymodel) of class glm

(glm.mymodeld$null.deviance - glm.mymodeld$deviance)

best, isaia

-------- Original Message --------
Subject: [R] Running a likelihood ratio test for a logit model
Date: Thu, 18 May 2006 02:20:54 -0500
From: Chris Bergstresser <chris at subtlety.com>
To: r-help at stat.math.ethz.ch

Hi all --

    I have to calculate a likelihood ratio test for a logit model.  I
found logLik, but I need to calculate the log likelihood for the model
without any predictors.  How can I specify this in glm?  If the full
model is glm(y ~ x1), is the one without predictors (y ~ 0)?  Or (y ~
1)?
    Is there a more direct way of getting this?

-- Chris

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