Re: Ratio of Cases to Regression Variables

Posted by lts1 on Mar 07, 2007; 4:31pm
URL: http://spssx-discussion.165.s1.nabble.com/Ratio-of-Cases-to-Regression-Variables-tp1074357p1074361.html

Hi Will,

    You might want to take a look at the article below.  Green argues that
the general rule of  X # of cases per predictors results in sample sizes
that may be unnecessarily large (is that possible?).  However, whether you
accept his formula or not doesn't really matter, because he gives references
for two or three other rules for estimating the sample size, which should
help.
    Green, S. B. (1991). How many subjects does it take to do a regression
analysis. Multivariate Behavioral Research, 26, 499-510.

    Best,
        Lisa

Lisa T. Stickney
Ph.D. Candidate
The Fox School of Business
     and Management
Temple University
[hidden email]


----- Original Message -----
From: "Will Bailey [Statman]" <[hidden email]>
To: <[hidden email]>
Sent: Wednesday, March 07, 2007 11:14 AM
Subject: Ratio of Cases to Regression Variables

>I know this has come up but can't find the reference or consensus
>statement:
>
> There is a "generally accepted" ratio of cases to the number of IVs in a
> regression, I believe it was something like 30 to 1 but not sure.
>
> Anyone recall or can offer insight.
>
> Tks,
> W
>