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Richard Feynman The Meaning Of It All
Atec Февраль 27 2008 22:52:48
Книга только для ознакомления
. Sounds stupid. Well, it is and it isn't. If you pick the hundred out by seeing which ones come through a low door, you're going to get it wrong. If you pick the hundred out by looking at your friends you'll get it wrong because they're all in one place in the country. But if you pick out a way that as far as anybody can figure out has no connection with their height at all, then if you find forty out of a hundred, then, in a hundred million there will be more or less forty million. How much more or how much less can be worked out quite accurately. In fact, it turns out that to be more or less correct to 1 percent, you have to have 10,000 samples. People don't realize how difficult it is to get the accuracy high. For only 1 or 2 percent you need 10,000 tries.
The people who judge the value of advertising in television use this method. No, they think they use this method. It's a very difficult thing to do, and the most difficult part of it is the choice of the samples. How they can arrange to have an average guy put into his house this gadget by which they remember which TV programs he's looking at, or what kind of a guy an average guy is who will agree to be paid to write in a log, and how accurately he writes in the log what he's listening to every fifteen minutes when a bell goes off, we don't know. We have no right, therefore, to judge from the thousand, or 10,000, and that's all it is, people who do this, who study what the average person is looking at, because there's no question at all that the sample is off
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