[R] chi-squared test

[juli g. pausas]

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

--
Juli G. Pausas
Centro de Estudios Ambientales del Mediterraneo (CEAM)
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Tel: (+ 34) 96 131 8227; Fax: (+ 34) 96 131 8190
mailto:juli at ceam.es
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