Performance measures

Introduction

Here is a selection of measures you can use for assessing the performance of your model.

Nash-Sutcliffe efficiency

This one is implemented as NSeff() in the topmodel package, and takes two vectors, containing the simulated (Qsim) and observed (Qobs) discharge:

  NSeff <- function (Qobs, Qsim){
     Qsim <- Qsim[!is.na(Qobs)]
     Qobs <- Qobs[!is.na(Qobs)]
     Qobs <- Qobs[!is.na(Qsim)]
     Qsim <- Qsim[!is.na(Qsim)]
     NS <- 1 - (sum((Qobs - Qsim)^2)/sum((Qobs - mean(Qobs))^2))
     return(NS)
  }
  Eff <- NSeff(Qobs,Qsim)