In regard to Dr. Trikalinos' recent -tabi, exact- inquiry:
> Perhaps I miss something, but
>
> . tabi 27879 35177 29377 17201 \ 118 187 183 65, e chi2
> yields Fisher's exact = 1.000
> Pearson's Chi2(3) =17.7, Pr =0.001
>
> StatXact calculates the P-value as 0.0005
> The command seems to work properly for smaller numbers or different
> table geometries.
>
He has indeed stumbled on a bug in the computations. For this problem the
results should be
. set rmsg on
r; t=0.00 13:47:01
. tabi 27879 35177 29377 17201 \ 118 187 183 65, e chi2
| col
row | 1 2 3 4 | Total
-----------+--------------------------------------------+----------
1 | 27,879 35,177 29,377 17,201 | 109,634
2 | 118 187 183 65 | 553
-----------+--------------------------------------------+----------
Total | 27,997 35,364 29,560 17,266 | 110,187
Pearson chi2(3) = 17.7073 Pr = 0.001
Fisher's exact = 0.001
r; t=0.93 13:47:04
. set rmsg off
. return list
scalars:
r(p_exact) = .000507590683298
r(p) = .0005054103814925
r(chi2) = 17.70731546856195
r(c) = 4
r(r) = 2
r(N) = 110187
I have been informed that a new executable update will be available by the
second week of January.
Thank you for bringing this problem to my attention.
-Rich
[email protected]
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