Percent perfect trading

摘要

What makes a trading system "good" and what makes a trading system "bad" is relative based on how well your money might have performed elsewhere — or is it? Here's one measure that not only provides an objective measure of system performance but can be used as a rather effective filter. The first rule of developing a trading system is test, test, test. Take as much historical data as you can get your hands on, from different markets, and from different time periods, and test your ideas on that data. Just because a system performs well for a year, or even for five years, does not mean that it will be any good on the next year or five.