https://github.com/cran/LearnBayes
Tip revision: 15f9a9eeec34caa6f192474de41d67165f0208f0 authored by Jim Albert on 07 October 2010, 00:00:00 UTC
version 2.12
version 2.12
Tip revision: 15f9a9e
pbetap.R
pbetap=function(ab,n,s)
{
#
# PBETAP Predictive distribution of number of successes in future binomial
# experiment with a beta prior. PRED = PBETAP(AB,N,S) returns a vector
# PRED of predictive probabilities, where AB is the vector of beta
# parameters, N is the future binomial sample size, and S is the vector of
# numbers of successes for which predictive probabilities will be computed.
#------------------------
# Written by Jim Albert
# albert@bgnet.bgsu.edu
# November 2004
#------------------------
pred=0*s;
a=ab[1]; b=ab[2];
lcon=lgamma(n+1)-lgamma(s+1)-lgamma(n-s+1);
pred=exp(lcon+lbeta(s+a,n-s+b)-lbeta(a,b));
return(pred)
}