Kitamura, Ryuichi and J. Supernak (1993) Temporal Utility Profiles of Activities and Travel: Some Empirical Evidence. Institute of Transportation Studies, University of California, Davis, Research Report UCD-ITS-RR-93-01
Studies that have examined the decision process underlying the choice of activity duration are few. Previous time use studies tended to examine the aggregate sum of time allocated to each category of activities. Some studies of activity engagement and time use adopt utility maximization framework and formulate econometric model systems. Other studies take on purely empirical approaches to determine the distribution of activity durations based on observation. The decision of terminating activity engagement, however, is not explicitly addressed in these studies.
In some instances, the duration of an activity is externally determined and no disengagement decision really takes place. An example is going to a theater to see a play. In this case the beginning and ending times of the activity seeing a play are externally determined. In other cases, activity durations are governed by stochastic processes that are beyond the control of the individual. Examples include visiting a bank to deposit checks. The time spent in the bank depends on the time spent waiting and the time required for the service. Both are clearly random.