A weighted matrix is a useful tool to help make choices between complex alternatives. A table is set up with each criterion given a weight depending on its importance in the decision and with each alternative given a ranking for that criterion. This particular method can serve a different purposes at each stage in your decision.
First, it can help to an analyze the problem, the task, or the objective by having them broken down into a number of requirements. Once the requirements have been determined, this method helps sorts them in their relative importance or weights.
A chart or matrix is created with two axis – choices on the vertical, and objectives/outcomes or benefits on the horizontal. At
the intersection of each, under objective, is put a number, the weighting, showing the relative importance of the attribute with respect to
the others. It should be emphasized that the sum of the weightings must equal unity. The weighting cannot be add indiscriminately
without adversely changing the others. For example, your total might be 1 or 100, and all weights must equal the sum.
If we are very familiar with the product and the requirements, the weights may be assigned directly. Otherwise, we can start by dividing 1
equally among the requirements, and then varying the weights in the weighted matrix as the relative importance of each requirement is
compared with the others, keeping the sum always equal to 1.