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Re:It’s not just p=0.048 vs. p=0.052 by bart_spoon on Wednesday September 11, 2019 @10:08AM (#20940364)
Its a meta observation of how we view p-values. He's saying that the same logic behind p-values and declaring something "statistically significant" when p < X (often 0.05), falls apart when applied to differences between two observed p-values. Essentially, you would say there is no "statistically significant" difference between an experiment that resulted in a p-value of 0.2 and one that resulted in a p-value of 0.05.

And the argument will hold no matter what threshold you choose for rejecting the null hypothesis. You can choose to reject if p > X, and for any X, there will be values greater than X that, applying this meta-logic, are not statistically different from X.

> At what point would this author say something is not consistent with the null hypothesis?

Gelman's argument, I presume, is against the idea of significance testing as a whole. Declaring something "statistically significant" is in itself a very problematic thing, as it distills the entire phenomenon, the uncertainty surrounding the experiment, and the uncertainty surrounding the researcher's decisions to a single, binary conclusion.

Gelman is a Bayesian (perhaps the most famous modern Bayesian), and the Bayesian philosophy is to focus on producing a posterior distribution of the phenomenon being studied. I presume the alternative to significance and null hypothesis testing that he was suggest would be something closer to a model where people are reporting their priors/data/posteriors, and the discussion focuses around the implications and replication of those.

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