Monday, April 23, 2007

Quote of the Week

"If you spend some time thinking about it ("ideal position sizing") you will realize that life just isn’t so simple. Every individual has different tolerances for different types of risks. A formula won’t capture all of them and a formula most certainly hides information that might be very valuable." -- Curtis Faith
Great article posted by Curtis today . Discusses some of what I found to be true in regards to the Sharpe Ratio and smoothness of returns. In fact, through much testing I have found using any type of volatility measure in my trading systems (entry, exit, position sizing, etc.) produces sub-par results when real-world results take effect. But, sometimes, those are the best measures we have. So, what do you do?

I think it's important to do what Curtis asks...
I’ll leave you with an exercise. Take your favorite position sizing methodology and then see what might happen if you happened to take the wrong side of a trade using that methodology on September 11th, 2001 or on Black Monday (October 19th, 1987).
In regard to formulas hiding valuable information. Pay attention to your stock data. There's a formula in there adjusting your time series for splits and possibly dividends. The longer term your system is...the more important this adjustment formula will play in your overall results. Common entry/exits formulas such as Average True Range (ATR) become rather out-of-date when processing IBM back in the 1960's. Something for all aspiring long-term trend-followers to consider when backtesting their systems.

Enjoy your week! I'm enjoying my first day of vacation since moving up to Missouri. And what a pretty day I picked out. What to do...what to do... ;-)

Later Trades,


No comments: