# function to calculate minF'
# according to ...
# H.H. Clark (1973). 
# The language-as-fixed-effect fallacy: A critique of language statistics in psychological research, 
# Journal of Verbal Learning and Verbal Behavior, 12, 335-359.
# this implementation was inspired by function summary.long.ssc : 
# # Sherry LaMonica, insightful.com
# # contributed to S-Plus discussion list, item #45,
# # http://spluscom.insightful.com/discussions/discussion3.cfm?topic_id=10&dept_id=6&discussionitemID=35&parentitemid=0#45
# 
# Hugo Quené, hugo dot quene at let uu nl, Utrecht inst of Linguistics OTS, Utrecht Univ
# 
# 20060220	first version
# 20061011	removed typo in computation of dfe
# 

minFprime <- function (F1,F2,df,n1,n2) { 

	dn <- list(c("F1", "F2", "df", "n1", "n2", "minF'", "df", "dfe", "prob"), "Value")

	value <- (F1 * F2) / (F1 + F2)
	dfe <- (F1+F2)^2 / ( (F1^2/n2)+(F2^2/n1) )
	dfe <- trunc(dfe)		# be conservative here: truncate, not round 
	pv <- 1-pf(value,df,dfe)

	sum.vec <- c(F1, F2, df, n1, n2, value, df, dfe, pv)
	mat <- matrix(sum.vec, ncol = 1) 
	dimnames(mat) <- dn 
	mat 
}