This method simulates a run which is a distance between a landing point and a final arriving point using an initial condition of a hit ball and an actually measured falling condition. Preferably, the initial condition includes initial side spin. Preferably, the falling condition is a falling velocity. Preferably, a calculation formula of the run is a quadratic function having the initial condition and the falling condition as variables. Preferably, when the run is defined as Dr (yard); a target direction component of the falling velocity is defined as Vx (m/s); a vertical direction component of the falling velocity is defined as Vy (m/s); and the initial side spin is defined as S (rpm), the run is calculated according to the following formula: Dr=Ci×Vx2−C2×Vx+C3×Vy2+C4×Vy−Cs×S+C6.