More on oenometrics

In today's National Post, columnist Barbara Kay tells an interesting story about wine tasting.

She and her husband had been invited to dinner, where the host decided to test attendees' wine-identifying skills. Ten wines were served, and guests had to identify the country from which each wine came.

The top score -- 10 out of 10 -- was submitted by Kay's husband, who "hadn't tasted a drop of wine but just for kicks filled out the ballot on the basis of mathematical probabilities."

Well, you can't guess wines with 100% accuracy just on an understanding of probability theory. So, *how*, exactly, did he do it? The odds of guessing 10 out of 10 different countries (assuming the list of ten countries was provided) are 1 in 3,628,800. Even if there were two wines for each of five countries, that would still be a 1 in 113,400 chance.

So how did Ms. Kay's husband do it? That was the most interesting part of the entire article, and we get no explanation at all.

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UPDATE: I e-mailed Ms. Kay, and she was kind enough to respond. It turnso ut that there were several small groups rather than one group of ten, as I had incorrectly assumed. If there were 2 groups of two and 2 groups of three, that would make the odds 1 in 144.

Her husband just tried to guess how the host would have permuted the answers -- for instance, he guessed that the first group of two was backwards, so that the lines on the scoring sheet would cross instead of being straight horizontal lines.

The moral of the story, I guess, is that if you're the host, choose the order of the answers by randomizing!

"Super Crunchers" -- Bill James and oenometrics

A few minutes ago, I started reading "Super Crunchers," by Ian Ayres. It's a book about how sabermetrics is better than intuition for finding things out. Of course, Ayres doesn’t use the word "sabermetrics," but that's what he means.

I'm only a few pages in, but already there's a great example. Economist Orley Ashenfelter looked at wine ratings, and figured out that the quality of a given year's vintage can be easily predicted from rainfall data. He produced this formula, which appears to have been derived from a simple regression:

Wine Quality = 12.145 + .00117 * winter rainfall + .0614 average growing season - .00386 harvest rainfall

The reaction from traditional wine experts was not surprising. Robert Parker, perhaps the world's most famous wine critic, said the method "was so absurd to be laughable." A wine magazine said "the formula's self-evident silliness invites disrespect."

However, it worked. Ashenfelter used the formula to predict that the 1989 vintage would be exceptional, and that 1990 would be even better. He turned out to be right.

That's the first six pages. On page 7, Ayres notes that the technique of wine sabermetrics can also be applied to sports. He calls Bill James the "Orley Ashenfelter of baseball," and talks a bit about Runs Created and Moneyball.

So now I'm nine pages into the book, and it looks very promising.

P.S. Appropriately, I think I remember a Joe Morgan baseball card from the '70s that said Joe is a wine connoisseur ...