Quantitative forecasting guesses things we can measure, things like revenue, births, and air pollution. Simulation substitutes for the real thing . We concentrate on a technique called Monte Carlo simulation, which brings the computer equivalent of rolling the dice to a great variety of situations. Common applications are scheduling, process flow, and market reactions. The Just in Time management philosophy has given inventory a bad name.
Inventory survives as a buffer between supply and demand.
Japan still stockpiles rice. Queuing Theory addresses the challenge of balancing the cost of waiting against the cost of providing service. This would be a problem of engineering and budgeting, except that queuing theory explicitly includes random events. Learning can be measured without answering how we learn, as individuals and as organizations. That is a great help in budgeting.