Re: [R] regression with proportion data

2012-03-19 Thread Peter Ehlers
On 2012-03-19 07:35, S Ellison wrote: -Original Message- From: r-help-boun...@r-project.org [mailto:r-help-boun...@r-project.org] On Behalf Of Georgiana May Sent: 19 March 2012 14:06 To: r-help@r-project.org Subject: [R] regression with proportion data I understand that the binomial f

Re: [R] regression with proportion data

2012-03-19 Thread S Ellison
> -Original Message- > From: r-help-boun...@r-project.org > [mailto:r-help-boun...@r-project.org] On Behalf Of Georgiana May > Sent: 19 March 2012 14:06 > To: r-help@r-project.org > Subject: [R] regression with proportion data > > I understand that the binomial function concerns succes

Re: [R] regression with proportion data

2012-03-19 Thread Jorge I Velez
Hi Georgiana, Take a look at the betareg package at http://cran.r-project.org/web/packages/betareg/index.html HTH, Jorge.- On Mon, Mar 19, 2012 at 10:05 AM, Georgiana May <> wrote: > Hello, > I want to determine the regression relationship between a proportion (y) > and a continuous variable (

Re: [R] regression with proportion data

2012-03-19 Thread Rubén Roa
Your response variable is not binomial, it's a proportion. Try the betareg function in the betareg package, which more correctly assumes that your response variable is Beta distributed (but beware that 1 and 0 are not allowed). The syntax is the same as in a glm. HTH Ruben -Mensaje origina

Re: [R] regression with proportion data

2012-03-19 Thread Doran, Harold
The logit link requires a binary response variable, not a proportion. Better bet is a beta regression. You can also do some stuff with linear regression if you do some transformations, but linear regression assumes the outcome is any number on the real number line bounded between -Inf and Inf.