Simulation system, simulation method, and simulation program

According to the present invention, a reception means 81 receives an estimator that has been trained using actual data from before a point in time in the past, receives verification data that is actual data from said point in time onward, and receives an update rule that stipulates, on the basis of an evaluation index, whether the estimator needs to be updated. A simulation means 82 simulates the evaluation index for the estimator with respect to a prescribed time period and/or update results for the estimator with respect to the prescribed time period on the basis of the update rule and of estimation results calculated by sequentially applying verification data for the prescribed time period to the estimator.