Experienced and Prospective Wait in Queues : A Behavioral Investigation

Problem definition: The cost of completing a line—a continuous variable—is typically studied indirectly through customers’ decisions to balk or renege from a queue—binary variables. However, these decisions only tell us whether a customer’s completion cost is above some (unknown) personal threshold; we do not have a good understanding of individuals’ precise completion costs, V. In this paper, we study how a perfectly informed customer in deterministic, visible queues forms her completion cost from (i) her position in line, (ii) the number of people that have been served since she joined the line, and (iii) the service speed. We also investigate how affective attitudes (emotional responses) towards waiting influence V.Methodology/results: Using a controlled experiment, we introduce the use of the Becker-DeGroot-Marschak (BDM) method (Becker et al. 1964) todirectly measure V. We find two important deviations from rational predictions. First, completion costs are not independent from subjects’ experienced wait (i.e., the wait they had to endure to get to their current position)—but the direction of this effect depends on subjects’ affective attitudes. Second, regarding the prospective queue, we find that length and service speed influence V additively, not multiplicatively. That is, subjects use heuristics; the completion cost is not directly proportional to the prospective waiting time.Managerial implications: Companies and organizations regularly offer customers paid options to shorten their waiting time, present them with alternatives to waiting in line, or use incentives to manage queuing congestion. Our results can help them by providing a granular metric of completion costs—measured in monetary terms—and by shedding light on how these costs are affected by the experienced wait (and hence the timing of the offer or incentive) and the characteristics of the prospective queue. Our clean experimental framework can also be easily extended to a wide array of queuing settings