<?xml version="1.0" encoding="utf-8"?><!DOCTYPE article  PUBLIC '-//OASIS//DTD DocBook XML V4.4//EN'  'http://www.docbook.org/xml/4.4/docbookx.dtd'><article><articleinfo><title>FAQ/Rfishp</title><revhistory><revision><revnumber>4</revnumber><date>2013-03-08 10:17:40</date><authorinitials>localhost</authorinitials><revremark>converted to 1.6 markup</revremark></revision><revision><revnumber>3</revnumber><date>2008-04-28 14:33:06</date><authorinitials>PeterWatson</authorinitials></revision><revision><revnumber>2</revnumber><date>2008-04-25 11:46:38</date><authorinitials>PeterWatson</authorinitials></revision><revision><revnumber>1</revnumber><date>2008-04-25 11:41:43</date><authorinitials>PeterWatson</authorinitials></revision></revhistory></articleinfo><section><title>R code for combining p-values using Bailey and Gribskov (1998) method</title><screen><![CDATA[pfish <- function(p) {
]]><![CDATA[
t <- prod(p)
x <- -log(prod(p))
n <- length(p)
v <- c(1:n-1)
a <- t*(x^v)/factorial(v)
pf <- sum(a)
return(pf)
}
pvals <- NA
pf <- function(pl) {
{ if (any(is.na(pl))) { res <- "There was an empty array of p-values"}
else
res <- pfish(pvals) }
return(res)
 }]]></screen><para>Running this inputting a list of pvalues on vector pvals </para><screen><![CDATA[pvals <- c(0.1,0.01,0.01,0.7,0.3,0.1)
pf(pvals)]]></screen><para>we get </para><screen><![CDATA[[1] 0.002148704]]></screen></section></article>