Introduction - If you have any usage issues, please Google them yourself
Patients have four indexes: X1: coagulation value; x2: prognosis index (related to age); X3: enzyme test value; X4 liver function test value. The data of 54 liver patients before operation and survival time after operation are shown in the table. The linear regression model of box Cox transformation variables Z and x1, X2, X3, X4 of patients' survival time is reasonable. The program realizes how to choose the optimal regression equation.