US EPA

3220125 

Journal Article 

The ASA’s statement on p-values: Context, process, and purpose 

Wasserstein, RL; Lazar, NA 

2016 

Yes 

American Statistician
ISSN: 0003-1305
EISSN: 1537-2731 

70 

2 

129-133 

English 

10.1080/00031305.2016.1154108 

WOS:000378462300001 

is supplemented by 3220126 - Supplemental material

In February 2014, George Cobb, Professor Emeritus of Mathematics and Statistics at Mount Holyoke College, posed these questions to an ASA discussion forum:

Q: Why do so many colleges and grad schools teach p = 0.05?
A: Because that’s still what the scientific community and journal editors use.
Q: Why do so many people still use p = 0.05?
A: Because that’s what they were taught in college or grad school.

Cobb’s concern was a long-worrisome circularity in the sociology of science based on the use of bright lines such as p < 0.05: “We teach it because it’s what we do; we do it because it’s what we teach.” This concern was brought to the attention of the ASA Board.

The ASA Board was also stimulated by highly visible discussions over the last few years. For example, ScienceNews (Siegfried 2010) wrote: “It’s science’s dirtiest secret: The ‘scientific method’ of testing hypotheses by statistical analysis stands on a flimsy foundation.” A November 2013, article in Phys.org Science News Wire (2013) cited “numerous deep flaws” in null hypothesis significance testing. A ScienceNews article (Siegfried 2014) on February 7, 2014, said “statistical techniques for testing hypotheses …have more flaws than Facebook’s privacy policies.” A week later, statistician and “Simply Statistics” blogger Jeff Leek responded. “The problem is not that people use P-values poorly,” Leek wrote, “it is that the vast majority of data analysis is not performed by people properly trained to perform data analysis” (Leek 2014). That same week, statistician and science writer Regina Nuzzo published an article in Nature entitled “Scientific Method: Statistical Errors” (Nuzzo 2014). That article is now one of the most highly viewed Nature articles, as reported by altmetric.com