wants <- c("DescTools")
has <- wants %in% rownames(installed.packages())
if(any(!has)) install.packages(wants[!has])
RunsTest()
from package DescTools
queue <- factor(c("f", "m", "m", "f", "m", "f", "f", "f"))
library(DescTools)
RunsTest(queue, alternative="greater")
Runs Test for Randomness
data: queue
runs = 5, m = 5, n = 3, p-value = 0.5714
alternative hypothesis: true number of runs is greater than expected
Run Length Encoding
lengths: int [1:5] 1 2 1 1 3
values : chr [1:5] "f" "m" "f" "m" "f"
[1] 5
f
3
m
2
getP <- function(r1, r2, n1, n2) {
# iterations of a symbol <= total number of this symbol?
stopifnot(r1 <= n1, r2 <= n2)
# probability in case r1+r2 is uneven
p <- (choose(n1-1, r1-1) * choose(n2-1, r2-1)) / choose(n1+n2, n1)
# probability in case r1+r2 is even: twice the uneven case
ifelse(((r1+r2) %% 2) == 0, 2*p, p)
}
f
7
p3.2 <- getP(3, 2, n1, n2)
p2.3 <- getP(2, 3, n1, n2)
p3.3 <- getP(3, 3, n1, n2)
p4.3 <- getP(4, 3, n1, n2)
[1] 0.5714286
p2.2 <- getP(2, 2, n1, n2)
p1.2 <- getP(1, 2, n1, n2)
p2.1 <- getP(2, 1, n1, n2)
p1.1 <- getP(1, 1, n1, n2)
[1] 0.4285714
[1] 1
muR <- 1 + ((2*n1*n2) / N)
varR <- (2*n1*n2*(2*n1*n2 - N)) / (N^2 * (N-1))
rZ <- (rr-muR) / sqrt(varR)
(pVal <- 1-pnorm(rZ))
f
0.4184066
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