Let me see whether I can bring some Kelly logic to this discussion.
Your goal is to make most money in the long run, subject to your risk tolerance. I typically have a running sharpe of about 3 over 3m, 6m, 1y interval and daily standard deviation of 1%. If running sharpe drops too low, I personally cannot handle it and subconsciously started to reduce risk/positions.
Remember according to kelly rule, your optimal position for continuous distribution is:
mean/var
which is same as
sharpe/std
So if you annualized sharpe is 3, which implies a daily sharpe of 0.2, you can choose to increase or decrease size/positioning based on your daily standard deviation and your risk tolerance / risk aversion.
Say if your daily standard deviation is about 2%, and your daily sharpe is 0.2, then you optimal kelly position is 0.2 / 2% = 10, which means you should size up 10 times more according to Kelly rule, which assumes a risk aversion of 1 (log utility or long run acct growth maximization). If your risk aversion is 10, then you are exactly doing the right positioning.
Furthermore, if you do lots of long-short, which is BP intensive, you might not be able to increase your positioning due to margin constraint. I typically take 5% or 10% of optimal kelly position.
njrookie
Your goal is to make most money in the long run, subject to your risk tolerance. I typically have a running sharpe of about 3 over 3m, 6m, 1y interval and daily standard deviation of 1%. If running sharpe drops too low, I personally cannot handle it and subconsciously started to reduce risk/positions.
Remember according to kelly rule, your optimal position for continuous distribution is:
mean/var
which is same as
sharpe/std
So if you annualized sharpe is 3, which implies a daily sharpe of 0.2, you can choose to increase or decrease size/positioning based on your daily standard deviation and your risk tolerance / risk aversion.
Say if your daily standard deviation is about 2%, and your daily sharpe is 0.2, then you optimal kelly position is 0.2 / 2% = 10, which means you should size up 10 times more according to Kelly rule, which assumes a risk aversion of 1 (log utility or long run acct growth maximization). If your risk aversion is 10, then you are exactly doing the right positioning.
Furthermore, if you do lots of long-short, which is BP intensive, you might not be able to increase your positioning due to margin constraint. I typically take 5% or 10% of optimal kelly position.
njrookie