Experimental Design
Our study design comprises two experimental parts, which are both artefactual field experiments in the classification of Harrison and List (2004)*. The first part is designed to observe procrastination – a behavioural implication of present bias – in high school students in an unobtrusive and naturalistic setting. In this part, we give the students an incentivised homework, consisting of a real-effort task requiring sustained attention, to be completed within a set deadline. We make use of the described interventions aiming at improving the timeliness of goal completion. The second part is designed to measure time preferences (i.e. an individual’s preference for when to do tasks and his or her bias for the present) for each student. For this part, we follow the experimental methodology of Augenblick, Niederle and Sprenger (2015)**.
Reflecting the two-part design, the study is executed over two separate periods. The first part takes place over the course of five weeks. At a first visit to the school, students fill out a background questionnaire, receive instructions and get to practice the homework task for the first part of the study. Two days later, the period to work on the homework task begins, which is up to four weeks long. Subsequently, we return to the school to introduce the second part of the study, which takes place over the course of three weeks.
*Harrison, G.W. and List, J.A. (2004). Field Experiments, Journal of Economic Literature, 1009-1055.
**Augenblick, N., Niederle, M. and Sprenger, C. (2015). Working Over Time: Dynamic Inconsistency in Real Effort Tasks, Quarterly Journal of Economics, 1067-1115.