First, you will need to determine what groups of items you would like to compare within your matrix. (You might want to use information garnered from another chart. For instance, you could use the end branches of a Tree Diagram as one group of items.) You can choose up to four separate groups of items. However, you can only compare two groups at a time. The shape of your matrix will depend on the number of groups you want to compare:
An L-shaped matrix will allow you to compare two groups of items. For instance, compare Group A with Group B.
A T-shaped matrix will allow you to compare two groups to a third group. For instance, compare Group A with Group B and compare Group C with Group A. Group A will be placed along the center of the T, so that it can be compared sepa"rately with B and C.
An X-shaped matrix will allow you to compare four groups. Each group can be compared to two other groups. For instance, compare Group A with Group B and Group C, compare Group B with Group A and Group D, compare Group C with Group A and D and compare Group D with Group B and Group C. Each group should have its items listed along a separate arm of the X.
A Y-shaped matrix will allow you to compare three groups. Each group can be compared with the other two groups.
Each item in the group will be compared, one at a time, to each item in the other group. Try to determine whether there is a relationship between the two items, and if so, whether this is a strong or weak relationship. Then mark the intersection of the two items.