Multi-Criteria Evaluation

The ability to solve for multi-criteria evaluation is at the core of IWalkways as described in Kalay 1995. Although this tool only looks at two major criteria for design, it does bring to light some important factors for decision making. For example, in figure 1, the system tells us that it is cheap to build a "y" pattern, but at the same time pedestrians might not like to make such sharp turns. Therefore a comprimise is needed to reasonably satisfy the two criteria (figures 2 and 3).

figures 1, 2, and 3: in figure 1, the detour heuristic oval is magenta, telling the user that this pattern is inconvenient for people to walk on (the top oval is not very important since this example was for north/south traffic). A better solution would be to drag the center node down into the lower arcs as in figure 2. In figure 3, too much emphasis is put on satifying the detour heuristic and not enough on cost.

Obviously, in addition to these two heuristics the designer also has his or her own factors to consider while working.

IWalkways