Diff for "FAQ/Rfishp" - CBU statistics Wiki
location: Diff for "FAQ/Rfishp"
Differences between revisions 1 and 2
 ⇤ ← Revision 1 as of 2008-04-25 11:41:43 → Size: 503 Editor: PeterWatson Comment: ← Revision 2 as of 2008-04-25 11:46:38 → ⇥ Size: 689 Editor: PeterWatson Comment: Deletions are marked like this. Additions are marked like this. Line 1: Line 1: = R code for combining p-values using Fisher's method = = R code for combining p-values using Bailey and Gribskov (1998) method = Line 32: Line 32: (I hope to improve this so that only the pvals vector needs to be entered for each run with the check to see if the p-value vector is empty done less obtrusively!)

# R code for combining p-values using Bailey and Gribskov (1998) method

```pfish <- function(p) {

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)
}```

Running this inputting a list of pvalues on vector pvals

```pvals <- c(0.1,0.01,0.01,0.7,0.3,0.1)
pl <- NA
pl <- length(pvals)
{ if (is.na(pl)) { res <- "There was an empty array of p-values"}
else
res <- pfish(pvals) }
print(res)```

we get

`[1] 0.002148704`

(I hope to improve this so that only the pvals vector needs to be entered for each run with the check to see if the p-value vector is empty done less obtrusively!)

None: FAQ/Rfishp (last edited 2013-03-08 10:17:40 by localhost)