tion of R-side task performance, has led to a model that only estimates R-side task load.
To compute task load, the times spent on individual tasks are summed, and thus assumed to be independent of one another and performed sequentially rather than concurrently. Model task times are generated primarily through GOMS modeling and from information obtained from consultations with subject matter experts.
To model PTT, which is an estimate of whether one or more controllers are required to work the traffic, requires information on total controller task load. Because the model only estimates R-side task load, various methods are employed to infer total task load. The method now being used, which employs fuzzy logic modeling, weights each R-side task according to its perceived D-side complexity. Although the D-side tasks are neither measured nor identified, these complexity weightings are treated as valid representations of D-side task loads because they were developed by using the judgment of operational experts.