Quote from verbotenlaandia:
Neke, maybe your realization that you tend to lose more frequently when you put up more cash could mean that you are perceiving that a particular stock is highly volatile...and then leveraging up to hit a home run. I guess the first question that I should ask would be: is your position sizing discretionary, or is that part of your program too?
Maybe you should either try using a similar position size on every trade (as your spreadsheet suggests), or you could even correlate the position size to something like front-month average implied volatility, derived from the stock's options, if available. For example, what would happen if you tried using a smaller position size for high IV trades, and vice versa?...which would probably be the opposite to what you've been doing. Just a thought...
My position sizing for my discretionary trades are discretionary. That is where the problem lies. Like you suggested I shall try and use a formula based on the stocks expected volatility (for me that depends on % move over prior-day's and the market cap or stock price). I will probably keep it simple for now and use just the overnight % move on the stock. Eventually I will let my system determine position size for even my discretionary trades - if I am away from home, I will route my request for trades remotely to my system at home. Any trade the system detects that was not routed thru it would be immediately closed. I haven't just found the time to automate a lot of the things I would like to automate.