[R] chi-squared test

[Sundardas Dorai-raj]

>>> "juli g. pausas" <juli at ceam.es> 12/18/01 05:52 AM >>>
> I don't quite understand the difference between the 
> two methods for
> performing a chi-squared test on contingency 
> tables:  summary(table())
> and   chisq.test()
> They may different results. E.g.:
> 
> aa <- gl(2, 10)
> bb <- as.factor(c
> (1,2,2,2,1,2,1,2,2,2,1,2,2,2,1,1,1,2,1,1))
> aa <- c(aa, aa)
> bb <- c(bb, bb)
> table(aa, bb)
> summary(table(aa, bb))
> chisq.test(aa, bb)
> 
> Could somebody give me some clues?
> Thanks in advance
> 
> Juli

>From help(chisq.test):

correct: a logical indicating whether to apply continuity correction
when computing the test statistic.

Setting correct=F gives the same answer as summary.table.

Sundar
-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-
r-help mailing list -- Read http://www.ci.tuwien.ac.at/~hornik/R/R-FAQ.html
Send "info", "help", or "[un]subscribe"
(in the "body", not the subject !)  To: r-help-request at stat.math.ethz.ch
_._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._