A method is considered for selecting mathematical models to fit frequency distributions of hydrologic data among ten commonly used methods of frequency analysis. The methods are those of Gumbel, Lieblein, Chow, and the seven types of Gringorten. The best fitting model is chosen on the basis of comparison for goodness of fit indicated by the coefficients of determination. Friedman's nonparametric statistical test was employed to detect significant differences between the models.