In a controlled lab experiment, we investigate hypothetical biases in the value of time by comparing stated preference (SP) and revealed preference (RP) values attached to unexpected waiting times. The SP and RP choice sets are identical in terms of design with the only difference being that the RP choices have real consequences in terms of unexpected waiting times and monetary incentives. We find a substantial hypothetical bias with the average SP value of time being only 70% of the corresponding RP value. The bias is mainly driven by participants who have scheduling constraints during the time of the unexpected wait. Scheduling constraints are taken into account to a much lesser extent in the SP setting than in the RP setting, presumably because only in the latter, the consequences of ignoring them are costly. We find evidence that this effect is stronger for persons with relatively low cognitive ability.

在受控实验室实验中，我们通过比较陈述的偏好（SP）和显示在意外等待时间上的显示的偏好（RP）值，调查时间值的假设偏差。SP和RP选择集在设计上是相同的，唯一的不同是RP选择在意外的等待时间和金钱激励方面具有真正的影响。我们发现一个很大的假设偏差，平均时间SP值仅为相应RP值的70％。偏差主要由在意外等待期间具有计划约束的参与者驱动。SP设置中考虑的调度约束比RP设置中考虑的约束要少得多，这大概是因为仅在后者中，忽略约束的后果是昂贵的。