A new paper published in Psychological Science reports a failure to replicate Study 2 of the influential article by Dan Ariely and Klaus Wertenbroch titled, "Procrastination, Deadlines, and Performance: Self-Control by Precommitment," originally published in 2002. The original study concluded that individuals performed better on tasks with externally imposed deadlines compared to self-set deadlines or a single deadline for all tasks. This study has been widely cited, with over 2,100 citations on Google Scholar.
The authors of the new paper, including Kyle Hyndman and Alberto Bisin, analyzed the original data after receiving it from Hyndman in 2006. They noted that the replication study was forthcoming and that they had requested additional data from Ariely, which was denied. The authors concluded that the data from the original studies were tampered with, based on their analyses.
In their assessment, they identified four major concerns regarding the original study's data. The first red flag was the size of the effect observed, which they deemed implausibly large given the small sample size. The second concern involved duplicate observations, where many participants reported identical results, suggesting potential data manipulation. The third issue was the lack of expected correlations among subjective measures of task evaluation, which were present in the replication study. Lastly, the original data showed no rounding in self-reported time estimates, which is atypical in such studies.
The authors have shared their findings in two posts, with the first focusing on Study 2 and the second on Study 1. They have also indicated that Ariely and Wertenbroch have requested the retraction of the original article from Psychological Science, a process that is currently ongoing.