Nash Sutcliffe Efficiency
An efficiency of 10 corresponds to a perfect match between model and observed data whereas an efficiency less than 00 occurs when the observed mean is a better predictor than the model.
Nash sutcliffe efficiency. However a method for estimating the statistical significance of sample values has not been documented. The nashsutcliffe efficiency is calculated as one minus the ratio of the error variance of the modeled time series divided by the variance of the observed time series. Note this model assumes the observed data is regularly spaced in time. In the situation of a perfect model with an estimation error variance equal to zero the resulting nash sutcliffe efficiency equals 1 nse 1.
Also factors that contribute to poor sample values are not well understood. Nash sutcliffe efficiency indicates how well the plot of observed versus simulated data fits the 11 line. The nash sutcliffe efficiency nse is a normalized statistic that determines the relative magnitude of the residual variance compared to the measured data variance nash and sutcliffe 1970. Nash sutcliffe efficiencies can range from infinity to 10.