[R] (no subject)
bob.ohara at helsinki.fi
Sun Oct 31 09:01:05 CET 2004
fang lai wrote:
> I have several questions regarding fisher.test() in
>R, and I'd highly appreciate any help with it.
> I have a group of observations, each having people's
>income, and an indicator of whether selected in or out
>a program. I want to test the difference between
>income of people who are in and out.
> Because the distribution is far from normal, I decide
>to use the fisher's exact test, using either mean or
>rank as statistics.
> Question 0 is: Can I do this test using fisher.test()
The answer is "no". I think you have mis-understood the purpose of
Fisher's exact test: read (and understand!) the description in the help
If your data were normall distributed, then you could use a t-test
(t.test()). As you are not happy with the normality assumption, you
could try an equivalent non-paramteric test, such as the Wilcoxon test
(wilcox.test()), also known as a Mann-Whitney test. I would recommend
that you make sure you understand how the test works first.
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