Multiple Criteria Analyses
Introduction
This technique is intended to be used to analyse a complex issue where many values (criteria) contribute to the final decision which needs to be as optimal as possible. Examples could be a large complex purchase contract with multiple bids or a project with multiple potential solutions. MCA is best carried out in a group, although a skilled individual with no preconception of the outcome could conduct an analysis.
Step one
First the group (or individual analyst) must decide what are the criteria (values or issues) that are influences on the final decision or outcome.
Cost is not recommended to be one of the criteria. See this issue in the last step.
Step two
Having decided on the criteria, the next step is to value the importance of each relative to each other. It is suggested that the most important is given a value of 10. There is no problem if several criteria have the same score, but the values should be a discriminating as possible i.e., using low values as well as high ones. The group must agree, and the values should only be changed in the process if there are a change in the overall situation. A jump in the energy cost of a project could be such an issue.
Step three
Now each bid or project is evaluated as to how well they achieve each of the criteria. Again 10 can be used for complete satisfaction of the criteria, giving a potential score of 100 for that single possible solution.
Step four
A spreadsheet is the obvious choice to log these various steps and the values assigned to them. The aggregate scores should then appear automatically.
The team now have the best choice, and the second and third choices.
With each of the choices there will be an associated cost. This cost can be changed by commercial negotiation, but a rational decision on the relative scores and associated costs is usually possible and straightforward.