#=====> Example 1: apple data <=====#
data(apple)
pest <- unique(apple$pesticide)
icc <- rep(-1, length(pest))
for(i in 1:length(pest)){
these <- apple$pesticide == pest[i]
r <- cor(apple$comp[these], apple$ss[these])
icc[i] <- cor2icc(r, 10,"within")
}
names(icc) <- pest
icc
#=====> Example 2: peach data <=====#
data(peach)
pest <- unique(peach$pesticide)
icc1 <- rep(-1, length(pest))
icc2 <- rep(-1, length(pest))
for(i in 1:length(pest)){
these <- peach$pesticide == pest[i]
r <- cor(peach$comp[these], peach$ss[these])
n <- mean(peach$items[these])
icc1[i] <- cor2icc(r, n, "not")
icc2[i] <- cor2icc(r, n, "within")
}
names(icc1) <- pest
names(icc2) <- pest
icc1 # correct
icc2 # incorrect based on data collection procedure
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