Konvertera Pearsons r till Cohens d, samt omvänt, och visa det grafiskt

effect-size.r

# r till d
rlist <- seq(0, 1, by=0.01)
dlist <- list()
i <- 0

for (r in rlist) {
  i <- i + 1
  dlist[i] <- sqrt(4 * r ^ 2) / (1 - r ^ 2)
}
dlist <- unlist(dlist)
plot(rlist, dlist, type="line", xlab="Pearsons r", ylab="Cohens d", main="Konvertering mellan effektstorlekar")


# d till r
dlist <- seq(-5, 5, by=0.1)
rlist <- list()
i <- 0

for (d in dlist) {
  i <- i + 1
  rlist[i] <- sqrt((d ^ 2) / (4 + d ^ 2))
}
rlist <- unlist(rlist)
plot(dlist, rlist, type="line", xlab="Cohens d", ylab="Pearsons r", main="Konvertering mellan effektstorlekar")