American Statistical Association statement on p-values

This is a re-directed post from Chuanpu Hu’s NMUsers post today.

The American Statistical Association (ASA) released a note on p-values. Here is a link to the full-text article and below is the email sent out to its members:

Dear Member,

Today, the American Statistical Association Board of Directors issued a statement on p-values and statistical significance. We intend the statement, developed over many months in consultation with a large panel of experts, to draw renewed and vigorous attention to changing research practices that have contributed to a reproducibility crisis in science.

“Widespread use of ‘statistical significance’ (generally interpreted as ‘p < 0.05’) as a license for making a claim of a scientific finding (or implied truth) leads to considerable distortion of the scientific process,” says the ASA statement (in part). By putting the authority of the world’s largest community of statisticians behind such a statement, we seek to begin a broad-based discussion of how to more effectively and appropriately use statistical methods as part of the scientific reasoning process.

In short, we envision a new era, in which the broad scientific community recognizes what statisticians have been advocating for many years. In this “post p < .05 era,” the full power of statistical argumentation in all its nuance will be brought to bear to advance science, rather than making decisions simply by reducing complex models and methods to a single number and its relationship to an arbitrary threshold. This new era would be marked by radical change to how editorial decisions are made regarding what is publishable, removing the temptation to inappropriately hunt for statistical significance as a justification for publication. In such an era, every aspect of the investigative process would have its appropriate weight in the ultimate decision about the value of a research contribution.

Is such an era beyond reach? We think not, but we need your help in making sure this opportunity is not lost.

The statement is available freely online to all at The American Statistician Latest Articles website. You’ll find an introduction that describes the reasons for developing the statement and the process by which it was developed. You’ll also find a rich set of discussion papers commenting on various aspects of the statement and related matters.

This is the first time the ASA has spoken so publicly about a fundamental part of statistical theory and practice. We urge you to share this statement with appropriate colleagues and spread the word via social media. We also urge you to share your comments about the statement with the ASA Community via ASA Connect. Of course, you are more than welcome to email your comments directly to us at

On behalf of the ASA Board of Directors, thank you!

Image removed by sender.
Jessica Utts
American Statistical Association

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Ron Wasserstein
Executive Director
American Statistical Association