Ed Thorp on Arbitrage

"It all depends on how confident you are about your edge. If you have a really strong conviction about your edge, then the best thing to do is sit there and take your lumps. If, however, you believe there is a reasonable chance that you might not have an edge, then you better have a safety mechanism that constrains your losses on drawdowns. My view on trend-following was that I could never be sure that I had an edge, so I wanted a safety mechanism. Whereas for a strategy like convertible arbitrage, I had a high degree of confidence as to the payoff probabilities, so reducing exposure on drawdowns was unnecessary."