Objective： To study the fitting with weibull distribution of five parameters for the differences （△E） of two dose-effect curves generated by the common four parameters equation of dose-effect curve, and build the analytical model of pharmacological specificity. Methods. The proper function of weibull distribu- tion was constructed to fit the AE of left skewed, right skewed or symmetrical distribution by least square method. The fitting results were assessed with coefficient of determination （R2）, residual standard deviation （Sy.x） and t...
