Monday, September 4, 2017

More on New p-Value Thresholds

I recently blogged on a new proposal heavily backed by elite statisticians to "redefine statistical significance", forthcoming in the elite journal Nature Human Behavior. (A link to the proposal appears at the end of this post.) 

I have a bit more to say. It's not just that I find the proposal counterproductive; I have to admit that I also find it annoying, bordering on offensive.

I find it inconceivable that the authors' p<.005 recommendation will affect their own behavior, or that of others like them. They're all skilled statisticians, hardly so naive as to declare a "discovery" simply because a p-value does or doesn't cross a magic threshold, whether .05 or .005. Serious evaluations and interpretations of statistical analyses by serious statisticians are much more nuanced and rich -- witness the extended and often-heated discussion in any good applied statistics seminar.

If the p<.005 threshold won't change the behavior of skilled statisticians like the proposal's authors, then whose behavior MIGHT it change? That is, reading between the lines, to whom is the proposal REALLY addressed?  Evidently those much less skilled, the proverbial "practitioners", who the authors evidently hope might be kept from trouble by a rule of thumb that can at least be followed mechanically.

How patronizing.


Redefine Statistical Significance

Date: 2017
Daniel Benjamin ; James Berger ; Magnus Johannesson ; Brian Nosek ; E. Wagenmakers ; Richard Berk ; Kenneth Bollen ; Bjorn Brembs ; Lawrence Brown ; Colin Camerer ; David Cesarini ; Christopher Chambers ; Merlise Clyde ; Thomas Cook ; Paul De Boeck ; Zoltan Dienes ; Anna Dreber ; Kenny Easwaran ; Charles Efferson ; Ernst Fehr ; Fiona Fidler ; Andy Field ; Malcom Forster ; Edward George ; Tarun Ramadorai ; Richard Gonzalez ; Steven Goodman ; Edwin Green ; Donald Green ; Anthony Greenwald ; Jarrod Hadfield ; Larry Hedges ; Leonhard Held ; Teck Hau Ho ; Herbert Hoijtink ; James Jones ; Daniel Hruschka ; Kosuke Imai ; Guido Imbens ; John Ioannidis ; Minjeong Jeon ; Michael Kirchler ; David Laibson ; John List ; Roderick Little ; Arthur Lupia ; Edouard Machery ; Scott Maxwell; Michael McCarthy ; Don Moore ; Stephen Morgan ; Marcus Munafo ; Shinichi Nakagawa ; Brendan Nyhan ; Timothy Parker ; Luis Pericchi; Marco Perugini ; Jeff Rouder ; Judith Rousseau ; Victoria Savalei ; Felix Schonbrodt ; Thomas Sellke ; Betsy Sinclair ; Dustin Tingley; Trisha Zandt ; Simine Vazire ; Duncan Watts; Christopher Winship ; Robert Wolpert ; Yu Xie; Cristobal Young ; Jonathan Zinman ; Valen Johnson

Abstract: We propose to change the default P-value threshold for statistical significance for claims of new discoveries from 0.05 to 0.005.