1. A job assignment apparatus comprising: a correlation calculation unit to calculate a correlation between an execution time used for processing a program that depends on a computer resource operating at the start of an execution request job and an execution time used for processing a predetermined amount of data in the execution request job which operates immediately after completion of an operation of the program; a resource identification unit to identify the computer resource on which the execution request job depends on the basis of the correlation calculated by the correlation calculation unit; and a job assignment unit to assign the execution request job to one of execution servers connected to the job assignment apparatus so as to exclude simultaneous execution of a job that depends on the same computer resource as the computer resource identified by the resource identification unit and the execution request job.