Time pressure heuristics can improve performance due to increased consistency.

Our goal is to demonstrate that potential performance theory (PPT) provides a unique type of methodology for studying the use of heuristics under time pressure. While most theories tend to focus on different types of strategies, PPT distinguishes between random and nonrandom effects on performance. We argue that the use of a heuristic under time pressure actually can increase performance by decreasing randomness in responding. We conducted an experiment where participants performed a task under time pressure or not. In turn, PPT equations make it possible to parse the observed change in performance from the unspeeded to the speeded condition into that which is due to a change in the participant's randomness in responding versus that which is due to a change in systematic factors. We found that the change in randomness was slightly more important than the change in systematic factors.