Analytic Hierarchy Process - Group Decision Making

SpiceLogic AHP Software supports group decision making. Each decision-maker can create an AHP project file and save it to a shared network location. Another user can then import those project files into the same AHP software and calculate an aggregated group decision.

No cloud setup is required. The important rule is that all member project files must use the same decision structure: the same criteria and subcriteria hierarchy, and the same options.

Here is an example. Suppose three decision-makers, Mike, Robert, and William, saved their AHP projects in these shared locations:

\\Network shared\\ahp decisions\\mike.ahpDecision
\\Network shared\\ahp decisions\\robert.ahpDecision
\\Network shared\\ahp decisions\\william.ahpDecision

Start AHP Software and click the Group Decision menu.

AHP Software Group Decision Making tab opened, the entry point for combining several team members' individual AHP project files into one aggregated decision.

Click the "Import member project files" button.

AHP Software Group Decision Making tab with the 'Import member project files' button highlighted, used to load each decision-maker's saved AHP project from a shared folder.

Click "Add a member" to add the first member project file.

AHP Software Group Decision Making panel with the 'Add a member' button highlighted, used to register the first decision-maker before pointing at their project file.

The member manager opens. From here, you can add, edit, or delete group members and their project-file paths.

AHP Software Member Manager dialog where group members are added, edited, or deleted along with the path to each member's individual AHP project file.

This is a typical member manager view after member project files have been loaded.

AHP Software Member Manager populated with several decision-makers and their loaded project files, ready to feed the group aggregation calculation.

After you add the member project files, the group decision aggregation is calculated automatically.

AHP Software Group Decision Making panel showing the automatically calculated aggregated priorities and recommended option once members' project files are loaded.

Aggregation Methods

SpiceLogic AHP Software supports two aggregation methods: AIJ (Aggregation of Individual Judgments) and AIP (Aggregation of Individual Priorities).

Aggregation of Individual Judgments

AIJ aggregates each member's pairwise comparisons using a weighted geometric mean. After the aggregated pairwise comparison matrices are built, the regular priority calculation method is used to calculate final option priorities.

For example, suppose Mike and Robert each have a pairwise comparison matrix. Each cell in the final aggregated matrix is created from the geometric mean of the matching cells in their matrices.

Worked example of the Aggregation of Individual Judgements (AIJ) method: each member's pairwise comparison is combined via weighted geometric mean before deriving final priorities.

Aggregation of Individual Priorities

AIP is simpler. It takes each member's final calculated priority for an option and then calculates the arithmetic mean.

For example, suppose Mike gives Car 1 a final priority of 0.3 and Car 2 a final priority of 0.7. Robert gives Car 1 a final priority of 0.2 and Car 2 a final priority of 0.8. The aggregated priority for Car 1 is the arithmetic mean of 0.3 and 0.2, which is 0.25. The aggregated priority for Car 2 is the arithmetic mean of 0.7 and 0.8, which is 0.75.

Worked example of the Aggregation of Individual Priorities (AIP) method: each member's final calculated option priorities are averaged (arithmetic mean) into the group result.

Selecting an Aggregation Method

In the Group Decision tab, use the two radio buttons to choose the aggregation method. By default, AIJ (Aggregation of Individual Judgments) is selected. Click the "i" button beside a method to see a visual explanation of how that method works.