创建一个二分类问题的数据集

actual <- c(1, 0, 1, 0, 1, 0, 1, 0, 1, 0) predicted <- c(1, 0, 0, 0, 1, 0, 1, 1, 1, 1)

计算准确度（Accuracy）

accuracy <- sum(actual == predicted) / length(actual) cat('Accuracy:', accuracy, '\n')

计算灵敏度（Sensitivity）

tp <- sum(actual == 1 & predicted == 1) fn <- sum(actual == 1 & predicted == 0) sensitivity <- tp / (tp + fn) cat('Sensitivity:', sensitivity, '\n')

计算特异度（Specificity）

tn <- sum(actual == 0 & predicted == 0) fp <- sum(actual == 0 & predicted == 1) specificity <- tn / (tn + fp) cat('Specificity:', specificity, '\n')