I'll take a look at it. -Jason
On Sat, Mar 12, 2005 at 08:18:22PM -0800, Ben Pfaff wrote: > John Darrington <[EMAIL PROTECTED]> writes: > > > Some of the values which are causing problems aren't particularly > > extreme. > > > > I'm suspecting a problem with lib/gsl_extras/betadistinv.c > > > > In particular gslextras_cdf_beta_Pinv. > > I have output for the same test when run with SPSS 12.0 on a > Windows machine. The diff against f.out produced by SPSS 12.0 > versus the values in the PSPP tests directory looks like this: > > 85c85 > < .50 2.00 1.00 1.50 .50 .13 > --- > > .50 2.00 1.00 1.50 .50 .12 > 98c98 > < .60 1.00 2.00 1.13 .60 .17 > --- > > .60 1.00 2.00 1.12 .60 .17 > 101c101 > < .60 2.00 1.00 2.62 .60 .06 > --- > > .60 2.00 1.00 2.63 .60 .06 > 172c172 > < .99 5.00 10.00 5.64 .99 .01 > --- > > .99 5.00 10.00 10.00 1.00 .00 > > (The columns are: > P df1 df2 i c p > where i = idf.f(P, df1, df2), > c = cdf.f(i, df1, df2), > and p = pdf.f(i, df1, df2).) > > Only a few values are off. The only one off by much is the > example you pointed out. A similar diff for the beta > distribution looks like this: > > 211c211 > < .99 .75 .25 1.00 .99 164383.5 > --- > > .99 .75 .25 1.00 .98 20860.76 > 218c218 > < .99 1.00 .25 1.00 .99 250000.0 > --- > > .99 1.00 .25 1.00 .98 46067.00 > 225c225 > < .99 1.50 .25 1.00 .99 431322.3 > --- > > .99 1.50 .25 1.00 .98 67836.74 > > (The columns are: > P a b i c p > where i = idf.beta(P, a, b), > c = cdf.beta(i, a, b), > and p = pdf.beta(i, a, b).) > > Here, only the extreme values are off as far as I can tell. I > suppose this must be the root of the problem though. > > (This is a good part of what I was going to bring up with Jason > anyhow.) > -- > "Long noun chains don't automatically imply security." > --Bruce Schneier > > > _______________________________________________ > pspp-dev mailing list > [email protected] > http://lists.gnu.org/mailman/listinfo/pspp-dev -- [EMAIL PROTECTED] SDF Public Access UNIX System - http://sdf.lonestar.org _______________________________________________ pspp-dev mailing list [email protected] http://lists.gnu.org/mailman/listinfo/pspp-dev
