[R] suggestion for proportions

[Bert Gunter]

Please! ...  ?prop.test

not t tests.

-- Bert

-- 

On Wed, Sep 7, 2011 at 4:21 AM, John Sorkin <JSorkin at grecc.umaryland.edu> wrote:
> >From you description, you should not used a paired Student's t-test. One uses a paired test when pairs of observations come from the same experimental unit (and thus are correlated). You describe a study where each experimental unit is tested once and where there are two independent groups of experimental units. Look at t.test (i.e. enter ?t.test).
> John
>
> John David Sorkin M.D., Ph.D.
> Chief, Biostatistics and Informatics
> University of Maryland School of Medicine Division of Gerontology
> Baltimore VA Medical Center
> 10 North Greene Street
> GRECC (BT/18/GR)
> Baltimore, MD 21201-1524
> (Phone) 410-605-7119
> (Fax) 410-605-7913 (Please call phone number above prior to faxing)
>
>>>> array chip <arrayprofile at yahoo.com> 9/7/2011 4:11 AM >>>
> Hi, I am wondering if anyone can suggest how to test the equality of 2 proportions. The caveat here is that the 2 proportions were calculated from the same number of samples using 2 different tests. So essentially we are comparing 2 accuracy rates from same, say 100, samples. I think this is like a paired test, but don't know if really we need to consider the "paired" nature of the data, and if yes then how? Or just use prop.test() to compare 2 proportions?
>
> Any suggestion would be greatly appreciated.
>
> Thanks
>
> John
>
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-- 
"Men by nature long to get on to the ultimate truths, and will often
be impatient with elementary studies or fight shy of them. If it were
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-- Maimonides (1135-1204)

Bert Gunter
Genentech Nonclinical Biostatistics