Calculate the Disease severity Index (DSI) (frequency of each class)
DSI2.Rd
This function calculates the Disease Severity Index (DSI) given a vector of classes, a vector of frequencies, and a maximum possible class value. The DSI is calculated as a weighted sum of class values, where each class is multiplied by its corresponding frequency, then divided by the product of the total frequency and maximum class value, and finally multiplied by 100 to get a percentage.