Full_Name: Charles J. Geyer Version: 1.1.1 OS: linux-gnu Submission from: (NULL) (134.84.86.22) prop.test(0, 30) 95 percent confidence interval: 0.003043053 0.141320480 Clearly absurd. You need theory to be this stupid. :-) I suggest adding if (p.c >= 1) p.u <- 1 just after line 59 of the current version of prop.test and if (p.c <= 0) p.l <- 0 just after line 62 of the current version of prop.test. With these patches, prop.test produces conservative confidence intervals for all p and n = 30. The current version fails catastrophically for 0 < p < .003 where of course it has actual coverage probability zero. -.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.- r-devel mailing list -- Read http://www.ci.tuwien.ac.at/~hornik/R/R-FAQ.html Send "info", "help", or "[un]subscribe" (in the "body", not the subject !) To: r-devel-request@stat.math.ethz.ch _._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._