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Comment by hogFeast

4 years ago

Lol. He must have never met anyone who has bet full Kelly.

Seriously. Full Kelly betting involves the use of significant leverage. The correct Kelly bet on the S&P index would be long 2.5x your total wealth.

  • You are right, but with execution risk / slippage it gets closer to 2x (2x and 3x are both close to 2.5x, but 2x has been performing better in the past).

  • it literally can't tell you to bet more than your bankroll.

    if you include margin in your bankroll, well, that's on your head.

    • Yes it can. Kelly can be applied to determine optimal leverage ratios. Assuming a risk free rate of zero, that formula is expected return divided by expected variance.

      so 10% expected return and 10% expected volatility, optimal Kelly is 10x leverage.