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Algorithm for calculating McCall's T-scores

2 messages · Stefan Björk

Stefan Björk
# 
I'm looking for a function or algorithm for calculating McCall's area
transformed T-scores, but have not find any. An algorithm is described
on http://www.visualstatistics.net/Visual Statistics
Multimedia/normalization.htm, but this seem to be an overly
complicated procedure for implementing in R.

/S
Stefan Björk
# 
I seem to have solved this on my own:

t.score.table <- data.frame(T=10:90,F=pnorm(10:90,mean=50.5,sd=10))
t.score <- function(x) {
  p <- ecdf(x)
  t <- cut(p(x),breaks=c(t.score.table$F,Inf),labels=t.score.table$T)
  t <- as.numeric(levels(t))[as.integer(t)]
  return(t)
}

/S

2008/12/18 Stefan Bj?rk <stefan.bjork at gmail.com>: