No. of Recommendations: 4
Absolutely. FCFLAN worked obscenely well only with a January start date. One wouldn't use it for any other month's start date. Isn't that fine so long as its performance in both good and bad years continues?

I think most people on tghe board would agree when I say no. The best indication of the true historic performance of a screen comes from averaging it s returns over all starting months (or all starting weeks if you have the data). The greater the variation among starting times the less reliable (more data mined?) the screen.

To explain, let me go back to red and white marbles and random sampling. Let's say you picked five marbles out of a bag and got all white. You repeated the exercise 11 more times and got various results. The average of all results was 3 white marbles and two red. Here are two possible conclusions:
1. The ratio of white to red marbles in the bag is probably close to 3:2.
2. You have a good chance of picking five white marbles on your first try, but not on other tries.

Which conclusion sounds more plausible?

Elan
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