doug141 writes "Analyzing for a difference is easy. But analyzing a difference of a differences is done incorrectly half the time in studies published in neuroscience journals.
Nieuwenhuis looked at 513 papers published in five prestigious neuroscience journals over two years. In half the 157 studies where this error could have been made, it was. They broadened their search to 120 cellular and molecular articles in Nature Neuroscience, during 2009 and 2010: they found 25 studies committing this fallacy, and not one single paper analysed differences in effect sizes correctly."
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