Simulation apparatus and simulation method

A simulation method performed by using a simulation apparatus that obtains a solution of a certain combinatorial optimization problem by simulated annealing, the simulation method comprising:

• a step of the simulation apparatus acquiring a local optimal solution of an objective function by using a local search method of changing a temperature parameter;
• a step of the simulation apparatus calculating a statistic based on the local optimal solution and a probability distribution function of a variable included in the objective function;
• a step of the simulation apparatus obtaining a maximum value and a minimum value as a search range for the temperature parameter based on the calculated statistic;
• and
• a step of the simulation apparatus obtaining the solution by executing the simulated annealing a plurality of times in the search range having the maximum value and the minimum value for the temperature parameter, wherein
• in the simulation apparatus, the statistic is a standard deviation related to a state of the local optimal solution, and a temperature when the standard deviation related to the state of the local optimal solution is larger than a predetermined threshold is set as the maximum value of the search range for the temperature parameter, and a temperature when the standard deviation related to the state of the local optimal solution is smaller than the predetermined threshold is set as the minimum value of the search range for the temperature parameter.