For improving wafer fabrication, yield and lifetime of wafers are predicted by determining coefficients of a yield domain for wafer yield prediction and a lifetime domain for a wafer lifetime prediction, an integral domain, an electric/layout domain, a metrology/defect domain, and a machine sensor domain in a hierarchical manner. With the aid of the hierarchically-determined coefficients, noises in prediction can be reduced so that precision of prediction results of the yields or the lifetimes of wafers can be raised.