IMPROVED STATISTICAL PROCEDURE FOR THE EVALUATION OF SOLAR-RADIATION ESTIMATION MODELS

The t-statistic is proposed as a statistical indicator for the evaluat ion and comparison of solar radiation estimation models. A relationshi p was developed for the t-statistic as a function of the widely used r oot mean square and mean bias errors. Using data published in the sola r energy literature, it was demonstrated that the use of the root mean square and mean bias errors separately can lead to the incorrect sele ction of the best model from a suite of candidate models. It is recomm ended that the t-statistic be used in conjunction with the root mean s quare and mean bias errors to more reliably assess a model's performan ce. The t-statistic has the added advantage of enabling the model test er to determine whether or not a model's estimates are statistically s ignificant at a particular confidence level.