[R] Why two chisq.test p values differ when the contingency table is transposed?

[Tao Shi]

I'm using R1.7.0 runing with Win XP.  Thanks,

...Tao


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>x
     [,1] [,2]
[1,]  149  151
[2,]    1    8
>t(x)
     [,1] [,2]
[1,]  149    1
[2,]  151    8
>chisq.test(x, simulate.p.value=T, B=100000)

        Pearson's Chi-squared test with simulated p-value (based on 1e+05 
replicates)

data:  x
X-squared = 5.2001, df = NA, p-value = 0.03774

>chisq.test(t(x), simulate.p.value=T, B=100000)

        Pearson's Chi-squared test with simulated p-value (based on 1e+05 
replicates)

data:  t(x)
X-squared = 5.2001, df = NA, p-value = 0.01642