Message-ID: <CB39400C59062045950FAEB4A28F10A5013ECB2C@BRIAREUS.net.ttu.edu>
Date: 2006-02-08T15:28:27Z
From: Cox, Stephen
Subject: Logistic regression - confidence intervals
Please forgive a rather na??ve question...
Could someone please give a quick explanation for the differences in conf intervals achieved via confint.glm (based on profile liklihoods) and the intervals achieved using the Design library.
For example, the intervals in the following two outputs are different.
library(Design)
x = rnorm(100)
y = gl(2,50)
d = data.frame(x = x, y = y)
dd = datadist(d); options(datadist = 'dd')
m1 = lrm(y~x, data = d)
summary(m1)
m2 = glm(y~x, family = binomial, data = d)
confint(m2)
I have spent time trying to figure this out via archives, but have not had much luck.
Regards
Stephen