1. A computer method for estimating a solution by successively improving solution vectors, the solution vectors being set for a problem having time sequential information, said computer method comprising the steps of: (a) inputting time sequential information associated with the operation of a target apparatus; (b) setting an initial set of solution vectors; (c) presenting said time sequential information expressed by each solution vector to a user; (d) receiving a value from the user which is indicative of an evaluation by the user of the suitability for solving the problem of each solution vector; (e) rearranging in accordance with each value received from the user the order in which the tine sequential information expressed by each solution vector are presented to the user; (f) calculating a fitness value of each solution vector based on the value received from the user; (g) performing an arithmetical genetic recombination operation on the solution vectors in the solution vector set based on the fitness value of each solution vector, thereby constructing a new solution vector set; and (h) adjusting the target apparatus operating on the time sequential information inputted in step (a) based on the solution, wherein step (c) through step (g) are iteratively performed until one of a number of iterations of steps (c) through (g) and the fitness value of one solution vector exceeds a predetermined threshold, thereby estimating the solution for the user.