Numerical Example

Below is a numerical example to illustrate how the Overall Attractiveness of the Italiana! restaurant was calculated.

1. The Italiana! value for the Food Quality attribute is 7. We can see from the Utility Curve (Figure 1) that the utility for 7 is 66.7. (Note: This chart is shown to illustrate this relationship. Optsee calculates the utility value automatically.) Table 1 shows the utility values for the other attributes, calculated in the same way from their respective utility curves.

Figure 1: Food Quality Utility Curve

Table 1: Individual Utility Values

2. The assigned weight and corresponding normalized weight for each attribute are shown in Table 2. These normalized weights are used to adjust the individual utility functions in the next step. Notice that even though the normalized weights are different than the assigned weights in the decision model, the relative importance of each attribute is the same. For example, the normalized weight for Atmosphere is still twice as much as the normalized weight for Cost (0.417÷0.208=2.005), and more than three times as important as Travel Time. (0.417÷0.125=3.336).

Table 2: Normalized Weights

3. Each individual utility is then multiplied by their respective normalized weighting factors to get the individual weighted utility values (Table 3).

Table 3: Individual Weighted Utility Values

4. The individual weighted utility values are then summed to yield the Overall Attractiveness:

16.7 + 10.2 +15.2 + 27.8 = 69.9