when you lose money, the market is rational. when you make money, you can say it was because of the market's inefficiency or irrationality. or maybe it is irrat

when you lose money, the market is rational. when you make money, you can say it was because of the market's inefficiency or irrationality. or maybe it is irrational to construct a trading strategy that relies so much on luck, with a few large trades that cannot be sufficiently characterized statistically. how can you know what your edge is, in terms of probabilities, on your long-term macro calls on oil or the dollar?