R-beta: Bug in dhyper (and phyper)
gb at stat.umu.se
Fri Apr 3 00:47:43 CEST 1998
I think I have found a bug in the function dhyper (R-0.61.2):
Warning: NAs produced in function "dhyper"
dhyper(x, N1, N2, n)
The hypergeometric distribution is used for sampling without replacement.
It has density
p(x) = Choose(N1, x) Choose(N2, n-x) / Choose(N1+N2, n)
for x = 0,...,n"
R> choose(3,0) * choose(3,0) / choose(6,0)
This result is correct, and obviously dhyper is implemented in some way
not consistent with the documentation.
Also note the spelling error of 'choose' in the documentation.
Goran Brostrom phone : +46 90 7865223
Department of Statistics 7865213 (secr)
Umea University fax : 7866614
S-90187 Umea, Sweden e-mail: gb at stat.umu.se
r-help 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-help-request at stat.math.ethz.ch
More information about the R-help