System, method, and recording medium having program recorded thereon

A method comprising:

• generating a production plan for controlling a production site during a target interval, using a planning model;
• generating a retrospective plan, which is a production plan that retrospectively reflects at least one of unplanned events that occurred after generation of the production plan, using the planning model;
• and
• analyzing production performance of the production site during the target interval, based on the production plan and the retrospective plan.

A recording medium recorded thereon a program that, when executed by a computer, causes the computer to function as:

• a planning section that generates a production plan for controlling a production site during a target interval, using a planning model;
• a retrospective planning section that generates a retrospective plan, which is a production plan that retrospectively reflects at least one of unplanned events that occurred after generation of the production plan, using the planning model;
• and
• an analyzing section that analyzes production performance of the production site during the target interval, based on the production plan and the retrospective plan.