Re: Deformed frogs back in the news

Edward M. Kennedy wrote:
"Kyle T. Jones" <KBfoMe@xxxxxxxxxxxxxx> wrote'

The heuristic guideline is wrong.

--Tedward
Even that isn't what the guy's claiming (IMO). As a general guideline, it's still fine in almost every scenario.

According to whom?


According to me, dewd. You know why? Because you can take any theory and then produce an infinite number of variations by simply introducing additional irrelevant entities or claims.

Now, which theory is best? The original one, or one of the infinite variants I produced? If you say the second, which of the infinite variants do you choose - remembering that you can't say "the most complex", because, given any variant (T), I can always create a yet-more-complex variant (T') by adding an additional irrelevant entity or claim.

Occam's Razor doesn't claim that a simpler explanation or theory is always correct or better - simply that, all other things being equal, you go with the least complex. For instance, there's no reason to introduce the guiding hand of God to evolution, because the results are the same in either case. You simply don't need anything beyond the interaction of mutation and random selection. And if you introduce the guiding hand of God, what's to stop me from introducing the guiding hand of Gods?

Besides, this Webb dewd doesn't seem to truly grasp Occam's Razor:

"Webb fed a computer different sets of real-life data, such as credit ratings and medical records, with some containing more than 3,000 examples. In each test, Webb used two approaches. One had the computer emulate Occam’s razor: After examining 80 percent of the data, the program would learn which attributes seemed to be important to whatever goal Webb had set, and which were irrelevant. The computer would then create a decision tree with the fewest branches and finally use that tree to try to classify the remaining 20 percent of the examples.

In the second approach, the computer again initially examined 80 percent of the examples. But instead of having the computer construct the simplest decision tree possible, it was programmed to consider additional decision-making criteria if doing so would help in the classification."

Nobody is claiming that introducing "additional decision-making criteria if doing so would *help* in the classification" wouldn't give you a better decision-making tree. This doesn't seem to have much to do with the Razor at all. It's the introduction of additional decision-making criteria that would be *irrelevant* in the classification that the Razor abhors.

HTH. HAND.

Cheers.
.

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