Re: [R] Logistic and Linear Regression Libraries

2009-10-31 Thread David Winsemius
On Oct 31, 2009, at 7:29 AM, tdm wrote: OK, I think I've figured it out, the predict of lrm didn't seem to pass it through the logistic function. If I do this then the value is similar to that of lm. Is this by design? Yes, at least for certain meanings of "this". When working with p

Re: [R] Logistic and Linear Regression Libraries

2009-10-31 Thread Mark Difford
tdm wrote: >> OK, I think I've figured it out, the predict of lrm didn't seem to pass >> it through the logistic >> function. If I do this then the value is similar to that of lm. Is this >> by design? Why would it >> be so? Please take some time to read the help files on these functions so th

Re: [R] Logistic and Linear Regression Libraries

2009-10-31 Thread tdm
OK, I think I've figured it out, the predict of lrm didn't seem to pass it through the logistic function. If I do this then the value is similar to that of lm. Is this by design? Why would it be so? 1 / (1 + Exp(-1 * 3.38)) = 0.967 tdm wrote: > > > Anyway, do you know why the lrm predict g

Re: [R] Logistic and Linear Regression Libraries

2009-10-31 Thread tdm
f disappointing, I think the answer to your question is > "no". You will need to seek out the algorithms from the published > information on them individually. > > W. > > From: r-help-boun...@r-project.org [r-help-boun...@r-project.

Re: [R] Logistic and Linear Regression Libraries

2009-10-31 Thread Mark Difford
Hi Phil, >> So far for logistic regression I've tried glm(MASS) and lrm (Design) and >> found there is a big >> difference. Be sure that you mean what you say, that you are saying what you mean, and that you know what you mean when making such statements, especially on this list. glm is not in

Re: [R] Logistic and Linear Regression Libraries

2009-10-31 Thread Bill.Venables
rg] On Behalf Of tdm [ph...@philbrierley.com] Sent: 31 October 2009 16:53 To: r-help@r-project.org Subject: [R] Logistic and Linear Regression Libraries Hi all, I'm trying to discover the options available to me for logistic and linear regression. I'm doing some tests on a dataset and want t

[R] Logistic and Linear Regression Libraries

2009-10-30 Thread tdm
Hi all, I'm trying to discover the options available to me for logistic and linear regression. I'm doing some tests on a dataset and want to see how different flavours of the algorithms cope. So far for logistic regression I've tried glm(MASS) and lrm (Design) and found there is a big differenc