Weighting waiting: A decision-theoretic taxonomy of delay, pacing and procrastination

Why do today, what you can fail to do tomorrow? How to pace or allocate work over time, whether to delay starting to work, and how much effort to exert are decisions people face daily. People sometimes procrastinate, facing detrimental effects due to delays. Previous research has recognised multiple shapes of pacing and types of procrastination, influenced by a myriad of psychological and situational factors. However, the main mechanistic explanation for delays and pacing, which concerns temporal discounting of distant rewards, focuses on only a subset. Here, we introduce a systematic taxonomy of pacing and procrastination, integrating multiple mechanistic routes to them within a common framework. The taxonomy is based on the sequence of temporal decisions involved in choosing how to distribute work in time, and shows how these decisions can be influenced by characteristics of the task and the (sub-)optimality of decision-making. Using reinforcement learning and decision-making models, we simulate diverse sources of pacing to illustrate aspects of the taxonomy and demonstrate how they give rise to different types of pacing and procrastination, showing the plausibility of our taxonomy. Our approach provides a theoretical foundation for understanding pacing and procrastination, enabling the integration of both established and novel mechanisms within a unified conceptual framework.