FAQ/perc - CBU statistics Wiki
location: FAQ / perc

How do I find out how many people have a score above a certain value?

Percentiles give the percentage of people who have a score below a threshold score.

Percentile (score) = 100 $$\frac{\mbox{n} \leq \mbox{score}}{\mbox{N}}$$

100 - Percentile (score) = 100 $$\frac{\mbox{n} \gt \mbox{score}}{\mbox{N}}$$

The score percentiles can be obtained by running the below in SPSS.

FREQUENCIES VAR=SCORE.
EXE.

or the below in R:

score <- sort(score)
perc <- rep(-99,length(score))
ict <- 1
b <- duplicated(score)
for (ict in 1:length(score) {
for (i in score) {
perc[ict] <- 100*sum(score<=i)/length(score)
ict <- ict+1
}
}
(percu <- perc[!duplicated(perc)])
(scoreu <- score[!duplicated(score)])
percu
scoreu

None: FAQ/perc (last edited 2013-03-08 10:17:13 by localhost)