Tuesday, March 14, 2017

"Whether" prediction works?

Much more snow was forecast. On the news they talked of a foot or more for NYC. We have less than they forecast.

Is this unusual? My very first review for Skeptic magazine, written under my male pseudonym, talked about this. The book was William Sherden's _The Fortune Sellers_ and his persuasive argument was that predicting the future doesn't usually work. That even with better equipment and better training, weather prediction is not going to _ever_ be more accurate than an estimate, and that not for more than a day or two ahead.

Sherden makes the same argument for stock market prediction. People pay big money for stock market prediction, and how often is it right?

Try it: maybe write down for, say, a week, what weather forecasters say, and then write down what happens. How right are they for seven days ahead? For the next day?

Do you own stock? Would it give you confidence to write down what the predictors say, and then, six months or a year later, compare it with what happened?