Identifying Constraints

Equally as important as defining objectives is identifying the constraints under which the study must be conducted. It does little good for simulation to solve a problem if the time to do the simulation extends beyond the deadline for applying the solution, or if the cost to find the solution exceeds the benefit derived. Objectives need to be tempered by the constraints under which the project must be performed such as the budget, deadlines, resource availability, etc. It is not uncommon to begin a simulation project with aspirations of developing an impressively detailed model or of creating a stunningly realistic animation only to scramble at the last minute, throwing together a crude model that barely meets the deadline.

Constraints should not always be viewed as an impediment. If no deadlines or other constraints are established, there is a danger of getting too involved and detailed in the simulation study and run the risk of "paralysis from analysis." The scope of any project has a tendency to shrink or expand to fill the time allotted.

In identifying constraints, anything that could have a limiting effect on achieving the desired objectives should be considered. Specific questions to ask when identifying constraints for a simulation study should include the following:

• What is the budget for doing the study?

• What is the deadline for making the decision?

• What are the skills of those doing the study?

• How accessible is the input data?

• What computer(s) will be used for the study?