Investigating Barry Crane’s Queen Rule

Here is Barry’s queen finding rule:
“The queen is over the jack in the minors and under the jack in the majors.”
I will look at two different interpretations of this rule–
First interpretation: We take it just as stated. Applying it whenever the Q and J are not held by the same side.
Second Interpretation: We add the qualifying condition “When our side has the A, K, and J of that suit.”
I don’t know which interpretation Barry had in mind so I will look at both of them. Given that Barry Crane played at a time before computer dealt bridge–we should test both computer dealt hands and human dealt hands.

I will test Barry’s rule against a random sample of hands. If Barry does significantly better than a coin flip then we will say that we found evidence supporting Barry’s rule. For example if Barry is right ten out of ten times that is equivalent to calling a coin flip correctly ten out of ten times, i.e. a probability of 1/1024 = 0.1%. That would be strong evidence for Barry. On the other hand if Barry is right six out of ten times, that could happen by chance with a probability of 38%. That result is not evidence supporting Barry. Our threshold for this experiment will be 10%, a very generous value for Barry. This is how science experiments are done.

For my sample of computer dealt hands I will use the most recent 50 deals that I played on BBO. You can get to your “recent” hands by logging in to BBO, clicking on the “History” tab, and then selecting “Recent hands” in the top menu of the History panel. For human dealt hands I will use the most recent six boards from our Sunday potluck bridge game together with the most recent twenty boards of Dick Hill’s duplicate game. Here are the results:

The “by chance” probabilities of 73% and 44% are way above our target of 10%. We found no evidence supporting Interpretation one of Barry’s rule.

The “by chance” probabilities of 96% and 80% are way above our target of 10%. We found no evidence supporting Interpretation two of Barry’s rule.

Once again I declare a Barry Crane rule to be utter rubbish. Who are you siding with–Barry Crane (one of the world’s greatest bridge players) or Patrick (aka Mr. IdeaHamster)?

[The “by chance” calculations were done on Google Sheets using the BINOMDIST function.]

[For more bridge quizzes click on Bridge Index page.]