This headliner appeared before, but to a sparse audience, so Management’s giving him another chance… His joke relates to both Senn’s post (about alternatives), and to my recent post about using (1 – β)/α as a likelihood ratio--but for very different reasons. (I’ve explained at the bottom of this “(b) draft”.)
….If you look closely, you’ll see that it’s actually not Jay Leno who is standing up there at the mike, (especially as he’s no longer doing the Tonight Show) ….
It’s Sir Harold Jeffreys himself! And his (very famous) joke, I admit, is funny. So, since it’s Saturday night, let’s listen in on Sir Harold’s howler joke* in criticizing the use of p-values.
“Did you hear the one about significance testers rejecting H0 because of outcomes H0 didn’t predict?
‘What’s unusual about that?’ you ask?
What’s unusual is that they do it when these unpredicted outcomes haven’t even occurred!”
Much laughter.
[The actual quote from Jeffreys: Using p-values implies that “An hypothesis that may be true is rejected because it has failed to predict observable results that have not occurred. This seems a remarkable procedure.” (Jeffreys 1939, 316)]
I say it’s funny, so to see why I’ll strive to give it a generous interpretation. Continue reading