Last time around I featured a simple scheme that could be used to fool investors into thinking they had found a genius at predicting the stock market. For some reason, in looking for examples of statistics, probability, and decision theory, it is relatively easy to find examples of how to use a bit of knowledge to extract treasure from someone who doesn’t share that background. I don’t know if that is a reflection of the opportunities that education brings or a reflection on the type of people who look for practical applications of my favorite subjects.

Maybe it is just the novelty. We all know that failure statistics play an important role in data storage and retrieval, but a Lockergnome column devoted to the economic tradeoffs of improving the performance of hard drives versus the increase in cost to maximize profits would result in a drastic reduction in readers. A column featuring a nifty card trick that could be the basis of winning some bar bets would draw a lot more interest - even if the underlying analysis was the same.

Not all is lost. Decision theory can be used by common people for things as remote as tracking down a lost island. Recently I found an interesting example of what appears to be a self-taught amateur named Robert Bittlestone who has applied the rudiments of decision theory to an interesting quest. This amateur is one of those delightful British enthusiasts who jump in with vigor and attack a problem that professionals have worried about for centuries. This amateur claims to have found the true home of Odysseus, the island of Ithaca. The catch is that ancient Ithaca is not the same as the island we currently identify by that name. To back it up, he has written a book, Odysseus Unbound. This is not a junk book of the new age, occult, or Da Vinci genres. It is a serious work that has received acclaim and discussion from experts in the field.

I can’t review here the various arguments from literature, archeology, geology, etc. that he uses to support his contention that ancient Ithaca is no longer obvious because, according to Bittlestone, it is no longer an island. He argues that it is now a peninsula attached within historical times to a nearby larger island. The channel that separated the two islands in Odysseus’ time is now filled. This is a bold hypothesis which he backs up with convincing arguments.

What caught my eye is that he went through the Iliad and Odyssey and recorded all mentions of the island of Ithaca and its surroundings. Then he constructed a table of testable statements from these excerpts. For instance, if some of the residents of the palace are reported to have looked out and seen a boat docking in the harbor, then we can test likely candidates by measuring whether the supposed harbor can be seen from the likely spot for a palace. That would be one testable statement. By itself, that does not help much, but by piling up many such statements, he could test each one against various of the conjectured sites and assign a composite score to the ensemble.

Similarly, he rated various features of the island by the presumed probability of it being true. For instance, having a harbor and a town associated with it overlooked by a palace placed on higher ground is likely to be true. Being guided through a foggy night to a servant’s hut by the goddess Athena is more likely fantasy. This formalism, which is somewhat arbitrary, has the advantage of providing an ordered array of possibilities. He might not have the sums right, but at least he provides a mechanism for combining statements in a way that demonstrates the power of multi-variant analysis.

Both of Bittlestone’s attempts to perform this multi-variant data analysis are primitive by many standards, but they have the advantage of providing a way of organizing data and allowing the computation of relative probabilities.

I liked the book and recommend it for general reading by anyone who is interested in the ancient Greeks, but it is also fun to see how a bright amateur goes about attempting to verify his solution to a puzzle that has bothered experts for more than 2000 years. The contrast between this honest amateur trying to use the scientific method to find truth and politicians, who tell us they know the truth, is heartening. Who knows, after seeing the many color photographs in his book, you might want to take your next vacation hopping around Greek isles.

In response to the interest my original tutorial generated, I have completely rewritten and expanded it. Check out the tutorial availability through Lockergnome. The new version is over 100 pages long with chapters that alternate between discussion of the theoretical aspects and puzzles just for the fun of it. Puzzle lovers will be glad to know that I included an answers section that includes discussions as to why the answer is correct and how it was obtained. Most of the material has appeared in these columns, but some is new. Most of the discussions are expanded compared to what they were in the original column format.

[tags]odysseus unbound,robert bittlestone,amateur archaeologist,iliad,odyssey[/tags]