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Updated: May 28, 2026

The Attentional Set Shifting Task: A Measure of Cognitive Flexibility in Mice
Published on: February 4, 2015
False-positive psychology: undisclosed flexibility in data collection and analysis allows presenting anything as
Joseph P Simmons1, Leif D Nelson, Uri Simonsohn
1Wharton School, University of Pennsylvania, Philadelphia, PA 19104, USA. jsimmo@wharton.upenn.edu
Abstract:
In this article, we accomplish two things. First, we show that despite empirical psychologists' nominal endorsement of a low rate of false-positive findings (≤ .05), flexibility in data collection, analysis, and reporting dramatically increases actual false-positive rates. In many cases, a researcher is more likely to falsely find evidence that an effect exists than to correctly find evidence that it does not. We present computer simulations and a pair of actual experiments that demonstrate how unacceptably easy it is to accumulate (and report) statistically significant evidence for a false hypothesis. Second, we suggest a simple, low-cost, and straightforwardly effective disclosure-based solution to this problem. The solution involves six concrete requirements for authors and four guidelines for reviewers, all of which impose a minimal burden on the publication process.
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