[R] validation logistic regression

2010-05-26 Thread azam jaafari
Hi   I did validation for prediction by logistic regression according to following:   validationsize - 23 set.seed(1) random-runif(123) order(random) nrprofilesinsample-sort(order(random)[1:100]) profilesample - data[nrprofilesinsample,] profilevalidation - data[-nrprofilesinsample,]

Re: [R] validation logistic regression

2010-05-26 Thread Joris Meys
Hi, first of all, you shouldn't backtransform your prediction, use the option type=response instead : salichpred-predict(salic.lr, newdata=profilevalidation,type=response) limit - 0.5 salichpredcat - ifelse(salichpredlimit,0,1) # prediction of categories. Read in on sensitivity, specificity

Re: [R] validation logistic regression

2010-05-26 Thread Frank E Harrell Jr
On 05/26/2010 07:00 AM, Joris Meys wrote: Hi, first of all, you shouldn't backtransform your prediction, use the option type=response instead : salichpred-predict(salic.lr, newdata=profilevalidation,type=response) limit- 0.5 salichpredcat- ifelse(salichpredlimit,0,1) # prediction of

Re: [R] validation logistic regression

2010-05-26 Thread azam jaafari
jorism...@gmail.com Subject: Re: [R] validation logistic regression To: azam jaafari azamjaaf...@yahoo.com Cc: r-help@r-project.org Date: Wednesday, May 26, 2010, 5:00 AM Hi, first of all, you shouldn't backtransform your prediction, use the option type=response instead : salichpred-predict

Re: [R] validation logistic regression

2010-05-26 Thread Frank E Harrell Jr
tell R that omit one by one data? Is validationsize=100? Thanks alot Azam --- On Wed, 5/26/10, Joris Meysjorism...@gmail.com wrote: From: Joris Meysjorism...@gmail.com Subject: Re: [R] validation logistic regression To: azam jaafariazamjaaf...@yahoo.com Cc: r-help@r-project.org Date