experiences such as a bus ride, a meal, and a college course unfold over time through a stream of transient states that may vary in intensity and even in sign from moment to moment. Such extended episodes can be depicted in the form of an experience pro®le, as illustrated in Exhibit 1 (see next page). Decision makers often evaluate the overall goodness or badness of extended episodes to assist future decisions or convey to others (presumably to aid them in making decisions). In some cases people evaluate the goodness or badness of episodes they experienced in the past; in other cases they predict the overall desirability of episodes that they have not yet experienced. Retrospective summary evaluations are an important input into decisions to repeat (or not repeat) past experiences; similarly, prospective summary evaluationsittis.
