What is Pugh Matrix and How to Use it ?

The Pugh Matrix is one of the most widely used methods of finding out the best solution once a number of alternate solutions have been generated. The success of the Pugh Matrix is in its simplicity. The tool is not very mathematically intensive and fairly simple to use. However, it has a record of coming up with the same solutions as mathematically intensive solutions would albeit with much less effort. Here is a step by step guide to use the Pugh Matrix.

Step 1: List down the Criteria in a Vertical List

The first step of the exercise is to list down the criteria that will be used for evaluation. The criteria is listed in a vertical list towards the extreme left of the paper or spreadsheet being used. Although the possible criteria could be many, the Pugh Matrix suggests using at least 3 viz. technological impact, cost impact and organizational acceptance.

Step 2: Select the Datum

The next step in the process is to select the Datum. The Datum is nothing but what the Six Sigma project team believes to be the initial most feasible solution. Selecting the appropriate datum is important because every solution will be evaluated against the datum.

Step 3: List down the Alternative Solutions Horizontally

After the datum, list down all the alternative solutions horizontally. This will create a matrix with the criteria on the vertical axis and the solutions on the horizontal axis.

Step 4: Marking the Pugh Matrix

Pugh Matrix is marked using “+”, “–” or “S”.

“+” means a particular solution scores better on a particular criteria as compared to the datum

“–” means a particular solution doesn’t score better on a particular criteria as compared to the datum

“S” means a particular solution scores the same on a particular criteria as compared to the datum

The datum by default has “S” rating assigned to all its criteria. This is because it is the same as itself and hence has the score 0.

No numerical values are assigned to the positives or negatives. This can be seen as one problem of the Pugh Matrix. If a solution is just a little inferior to the datum or very inferior to the datum, both will receive the same score on the matrix. However, this is where the Pugh Matrix relies on human judgement.

Step 5: Aggregating the Scores

The scores are aggregated by counting the number of “+” and “–” that a solution has. Many times weights are attached to criteria. Thus gaining a “+” on 1 criteria will be considered as 1.5 “+” while aggregating the scores.

The “+” and “–” are then used to compare the final score. If any solution has a score greater than 0 i.e. greater than the datum, it is considered for selection. If all the scores are less than “0”, then the datum is selected as the final solution.