Pairwise generated Interrelationship Diagraph (PID) is an enhanced version of the commonly used Interrelationship Diagraph (ID). The following points explain why PID is easier and better to use than the traditional ID.
The following figure shows a PID generated using ConceptStar software.
The following steps show how a traditional ID is constructed. (PID does not require many of the steps described below due to computer assisted construction)
1. Define an issue or problem and collect the related ideas (5 to 25 ideas).
2. Write the ideas on cards in large letters and arrange them in a large circular pattern on a wall or other surface such that arrows can be easily drawn between them.
3. Work with one idea-pair at a time to determine the direction of the dominant influence and draw an arrow representing that influence. If the influence is deemed to be equal in both directions, the idea pair can be collapsed as one idea-set by putting the two cards together.
4. Work through all of the idea pairs to draw the influence arrows.
5. If there are a large number of ideas in the Interrelationship Digraph, select the ideas with the most in-arrows and out-arrows to construct a simpler final Interrelationship Digraph.
6. The ideas or issues with a large number of out-arrows are the root cause or drivers, and the ones with a large number of in-arrows are the outcomes.