Re: [R] Negative intercept in glm poisson model

From: Douglas Bates <>
Date: Wed 02 Mar 2005 - 00:31:46 EST

Federico Gherardini wrote:

> I'm trying to fit a glm model using family=poisson(link = "identity"). The
> problem is that the glm function fits a model with a negative intercept,
> which sounds like a nonsense to me, being the response a Poisson variable.

Not really. The negative intercept is on the scale of the linear predictor. The expected response, which is the exponential of the linear predictor, is always positive. mailing list PLEASE do read the posting guide! Received on Wed Mar 02 00:50:23 2005

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