[R] CORR! confidence interval for the logit - predict.glm

2008-05-28 Thread Christine Sonvilla
Sorry, in my previous email I forgot two commands for the prediction: upperlogit <- predictionlogit$fit + 2*predictionlogit$se.fit lowerlogit <- predictionlogit$fit - 2*predictionlogit$se.fit I've included them in the email below again! Dear Brian and list members, Thanks very much for your

Re: [R] confidence interval for the logit - predict.glm

2008-05-28 Thread Christine Sonvilla
Dear Brian and list members, Thanks very much for your response Brian! I applied the adjusted calculation that you advised me to use [1/(1+exp(-upperlogit))] and as a result I don't get any more NA values in my upper confidence interval values. Yet, some outcomes are very akward, since for ver

[R] confidence interval for the logit - predict.glm

2008-05-28 Thread Christine Sonvilla
Hello all, I've come across an online posting http://www.biostat.wustl.edu/archives/html/s-news/2001-10/msg00119.html that described how to get confidence intervals for predicted values from predict.glm. These instructions were meant for S-Plus. Yet, it generally seems to work with R too, b