Petra on Programming: Truncated Indicators

Cumulative indicators, such as the EMA or MACD, are affected not only by previous candles, but by a theoretically infinite history of candles. This makes them return slightly different results depending on the tested period. Although this effect is often assumed negligible, John Ehlers demonstrated in his July S&C article that it is not so. At least not for some indicators, such as a narrow bandpass filter. Continue reading “Petra on Programming: Truncated Indicators”

Build Better Strategies! Part 2: Model-Based Systems

Trading systems come in two flavors: model-based and data-mining. This article deals with model based strategies. Even when the basic algorithms are not complex, properly developing them has its difficulties and pitfalls (otherwise anyone would be doing it). A significant market inefficiency gives a system only a relatively small edge. Any little mistake can turn a winning strategy into a losing one. And you will not necessarily notice this in the backtest.  Continue reading “Build Better Strategies! Part 2: Model-Based Systems”