fisher.test - can I use non-integer expected values?
On Dec 10, 2013, at 2:04 PM, bakerwl wrote:
I seem to be able to use expected values that are decimal (e.g., 1.33) when using chisq.test but not when using fisher.test.
There are no expected values in the input to fisher.test.
This happens when using an array/matrix as input. Fisher.test returns: Error in sprintf(gettext(fmt, domain = domain), ...) : invalid format '%d'; use format %s for character objects. Thus, it appears fisher.test is looking for integers only.
That would seem to be a very reasonable assumption.
I tried putting the data in x and y factor objects, but that does not work either. Is there another way to use non-integer expected values with fisher.test or is that a limitation of fisher.test?
If I must use integer expected values, I suppose one option would be round the expected value down or up to an integer. But, which? I tried that, but they produce different p values.
Well, of course. First, you tell us why you need `fisher.test` at all. It says very clearly it is for count data and you clearly want to do something with input that is not counts. `prop.test` will test a distribution of counts against expected proportions and `binom.test` will do an exact test of a Bernoulli experiment against (one) proportion.
Thanks for any help! View this message in context: http://r.789695.n4.nabble.com/fisher-test-can-I-use-non-integer-expected-values-tp4681976.html Sent from the R help mailing list archive at Nabble.com.
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