A classifier often turns probabilities into labels by comparing each score with a cutoff.

Program

Play the script to change the cutoff and see how many records are classified as yes.

classification_threshold.R
cutoff <- 
prob <- c(0.20, 0.65, 0.80, 0.55)
predicted <- ifelse(prob >= cutoff, "yes", "no")
yes_count <- sum(predicted == "yes")
label <- paste("yes", yes_count, sep = ":")
cat(label, "\n", sep = "")
cutoff <- 
prob <- c(0.20, 0.65, 0.80, 0.55)
predicted <- ifelse(prob >= cutoff, "yes", "no")
yes_count <- sum(predicted == "yes")
label <- paste("yes", yes_count, sep = ":")
cat(label, "\n", sep = "")
cutoff <- 
prob <- c(0.20, 0.65, 0.80, 0.55)
predicted <- ifelse(prob >= cutoff, "yes", "no")
yes_count <- sum(predicted == "yes")
label <- paste("yes", yes_count, sep = ":")
cat(label, "\n", sep = "")
probability Scores near 1 are stronger evidence for the positive class.
threshold `prob >= cutoff` creates one decision per score.
label count Counting labels gives a quick summary of classifier output.