Calculate Youden's index
youdensIndex(actuals, predictedScores, threshold = 0.5)The youdensIndex of the given binary response actuals and predicted probability scores, which is calculated as Sensitivity + Specificity - 1
The actual binary flags for the response variable. It can take a numeric vector containing values of either 1 or 0, where 1 represents the 'Good' or 'Events' while 0 represents 'Bad' or 'Non-Events'.
The prediction probability scores for each observation. If your classification model gives the 1/0 predcitions, convert it to a numeric vector of 1's and 0's.
If predicted value is above the threshold, it will be considered as an event (1), else it will be a non-event (0). Defaults to 0.5.
This function was obtained from the InformationValue R package (https://github.com/selva86/InformationValue).