1. A method for estimating distribution characteristics of product parameters, the method comprising: determining n number of product parameters that characterize a product; determining m number of characteristic parameters dependent on the product parameters; determining m number of correlation functions that represent the characteristic parameters in terms of the product parameters; obtaining inverse functions of the correlation functions that represent the product parameters in terms of the characteristic parameters; fabricating test products to empirically determine quantitative relations between the product parameters and characteristic parameters; obtaining k numbered measured data of the characteristic parameters by measuring k number of the test products; and estimating statistical characteristics of the product parameters corresponding to a distribution of the measured data of the characteristic parameters using the inverse functions of the correlation functions.