On 21 Oct 2003 05:44:47 GMT, David Duffy <[EMAIL PROTECTED]> wrote: > Rich Ulrich <[EMAIL PROTECTED]> wrote: [ ... ] > > On 17 Oct 2003 06:05:19 -0700, [EMAIL PROTECTED] (Enda Kelly) [ editing and rearranging the table ] > >> Locus pair P-value Median Lower Upper > >> 1 0.002414 0.002422 0.000055 0.037401 > >> 4 0.018936 0.016100 0.001082 0.193285
> >> 2 0.971621 0.512296 0.181935 0.850761 > >> 5 0.832001 0.505662 0.173286 0.857703 [ ... ] RU > > > > It looks to me as if #1 and 4 show a huge range, when > > judged by the appropriate standard of relative size. > > > But, more important, #2 and 5 are unbelievable. > > That is, I would say that they are not 'useful' results. > > Either, they were not good candidates for bootstrapping, > > or something is wrong that is more serious than that. DD > > They are actually what you expect, I think, from a noncentral > chi-square. If sampling from a 1-df central chi-square, for example, one would > expect 95% of samples to fall between 0.001 and 5.02, wth the "95% CI" for the > P-values ranging from 0.05 all the way up to 0.95. By contrast, for David, you mis-read, I hope. I can see that your description fits what I said about #1 and #4. Yes, I was not surprised by the wide, multiplicative range of the p-levels. The original poster called those *narrow* since the whole action was within a percentage point; I objected. It was just the #2 and #5 that were not 'useful' results, since the point estimate is outside the CI, for #2, and nearly so for #5. That can happen, but it is pathological. Agreed? -- Rich Ulrich, [EMAIL PROTECTED] http://www.pitt.edu/~wpilib/index.html "Taxes are the price we pay for civilization." . . ================================================================= Instructions for joining and leaving this list, remarks about the problem of INAPPROPRIATE MESSAGES, and archives are available at: . http://jse.stat.ncsu.edu/ . =================================================================
