Why do people automatically jump to Fisher's Exact test? That test conditions on BOTH marginal row totals. Usual contingency table analyses condition on one margin, at most. You should look very carefully at the underlying model for your data. Fisher's Exact test might not be appropriate. Agresti's "Categorical Data Analysis" has a good discussion of this.
Simon. On Tue, 2008-01-15 at 21:49 -0500, My Coyne wrote: > Thank you for your help; I will try fisher.test(). > > > > > > From: anna freni sterrantino [mailto:[EMAIL PROTECTED] > Sent: Tuesday, January 15, 2008 8:53 PM > To: [EMAIL PROTECTED]; [EMAIL PROTECTED] > Subject: Re: [R] In chisq.test(x) : Chi-squared approximation may be incorrect > > > > Hi! > the warning you got > "Chi-squared approximation may be incorrect" > is because probably there are less than 5 observations in > the cell. Maybe will help to > try fisher.test() > > Cheers > > Anna > > > > > > > > > ----- Messaggio originale ----- > Da: My Coyne <[EMAIL PROTECTED]> > A: [EMAIL PROTECTED] > Inviato: Lunedì 14 gennaio 2008, 21:51:30 > Oggetto: [R] In chisq.test(x) : Chi-squared approximation may be incorrect > > Hello, > > > > I received the following warning when running chi-square; > > n Is there a way to catch the 'error' code of 'warning' after run > chisq.test(x)? > > n What does this error mean? > > > > Thank you for your help. > > > > > > > [[alternative HTML version deleted]] > > ______________________________________________ > R-help@r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code. > > > > > > _____ > > _____ > > L'email della prossima generazione? Puoi averla con la nuova > <http://us.rd.yahoo.com/mail/it/taglines/hotmail/nowyoucan/nextgen/*http:/it.docs.yahoo.com/nowyoucan.html> > Yahoo! Mail > > > [[alternative HTML version deleted]] > > ______________________________________________ > R-help@r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code. -- Simon Blomberg, BSc (Hons), PhD, MAppStat. Lecturer and Consultant Statistician Faculty of Biological and Chemical Sciences The University of Queensland St. Lucia Queensland 4072 Australia Room 320 Goddard Building (8) T: +61 7 3365 2506 http://www.uq.edu.au/~uqsblomb email: S.Blomberg1_at_uq.edu.au Policies: 1. I will NOT analyse your data for you. 2. Your deadline is your problem. The combination of some data and an aching desire for an answer does not ensure that a reasonable answer can be extracted from a given body of data. - John Tukey. ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
