Today another guest post. In this post, Fernanda Ferreira and John Henderson respond to the recent and instantly (in)famous multi-authored proposal to lower the level of statistical significance to .005. If you want to discuss this post, Twitter is the medium for you. The authors' handles are @fernandaedi and @JhendersonIMB. Fernanda Ferreira John M. Henderson Department of Psychology and Center for Mind and Brain University of California, Davis The paper “Redefine Statistical Significance” (henceforth, the “.005 paper”), written by a consortium of 72 authors, has already made quite a splash even though it has yet to appear in Nature Human Behavior. The call to a redefinition of statistical significance from .05 to .005 would have profound consequences across psychology, and it is not clear to us that the broad implications across the field have been thoroughly considered. As cognitive psychologists, we have major concerns about the advice and the rationale for t