Applying EST ScriptBots to SP Daily Follow Through Systems
Introduction
This article describes the method and results of applying confidence based Ensemble Signal Trader (EST) BioComp Dakota ScriptBots to two very simple base systems. This research was inspired by the writings of Michael Stokes on his MarketSci blog. Thanks to Michael for providing what I consider to be a valuable education to his readers . The systems use continually linked reverse adjusted closing data for the SP futures contract provided by Pinnacle Data Corp. The start date for the trading simulations is January 1, 2005. In my opinion, this is not enough data for quality research. I’m ‘dipping my toe in the water’ here.
System Sp_CounterTrend goes or stays long as at today’s close if today’s closing price is lower than yesterday’s closing price and goes or stays short as at today’s close if today’s closing price is higher than yesterday’s closing price. System Sp_TrendFollower goes or stays long as at today’s close if today’s closing price is higher than yesterday’s closing price and goes or stays short as at today’s close if today’s closing price is lower than yesterday’s closing price (opposite to Sp_CounterTrend). Both systems use the Delta ScriptBot, one has the Counter Indicator parameter set to 1 (true) and the other to 0 (false).
As individual systems, Sp_CounterTrend and Sp_TrendFollower are not adaptive in any way. The purpose of applying EST ScriptBots to the signals generated by these two systems is to create a master system that adapts to the persistence / anti-persistence of the daily trend. No trading costs have been applied as the purpose of this research is not to assess the viability of a trading system.
Base Systems Configuration
The screen images that follow illustrate the configuration of the two base systems.

Sp_CounterTrend Data Settings
The Delta Period is set to 1 on the Bots and Swarm tab within the Dakota application. The number of Bots is set to 1 because no parameters are being adapted using the swarm.

Sp_CounterTrend Bots And Swarm Settings
The system hypothetically trades at the close of the most recent day session so a trading delay of zero is used.

Sp_CounterTrend Equity Management Settings
The configuration of Sp_TrendFollower is the same as Sp_CounterTrend except the Counter Indicator parameter on the Bots and Swarm tab is set to zero.

Sp_TrendFollower Bots And Swarm Settings
Base Systems Performance
Screen images of the equity curves and hypothetical trade statistics for the base systems follow. It is clear that system Sp_CounterTrend performed much better than it’s converse system over this time period. Note the steadily declining equity curve from approximately April 2006 to April 2007 for this system. I would like to see the master system produce an upwardly sloping equity curve over this period.

Sp_CounterTrend Price Signal Equity Charts

Sp_CounterTrend Trade Statistics
Sp_TrendFollower produces a mostly downward sloping equity curve. If the EST ScriptBot does it’s job then the periods of poor performance will not be reflected in the master system.

Sp_TrendFollower Price Signal Equity Charts

Sp_TrendFollower Trade Statistics
Ensemble Signal Trader Systems Configuration
EST ScriptBots that calculate and apply confidence based weights to the input signals will be used to build master systems. ScriptBot EST-Confidence-Weighted calculates a weighting for each input signal that is based on the performance over the adapted lookback period relative to a confidence threshold that specifies what level of performance is required to have 100% confidence in the signal. The weightings are multiplied by each input signal and averaged to determine the output signal. Performance is measured in terms of either proportion of perfect, net direction correct or weighted net direction correct. If the confidence weighting is less than 5% then it is set to zero.
ScriptBot EST-PolarConfidence-Weighted is similar to EST-Confidence-Weighted, however, negative confidence values are applied. If the absolute value of the confidence weighting is greater than or equal to 5% then the signal is used, otherwise a weighting of zero assigned. Thereby, if a signal has produced significantly poor performance over the lookback period then it still contributes to the master system signal without the inclusion of it’s converse system. Only one of the base system signals is required for the system that uses ScriptBot EST-PolarConfidence-Weighted, however, both base systems signals will be used in this case.
The screen images that follow illustrate the configuration of the two EST systems. Note that the signals generated by the two base systems have been added to the Ticker list and that the Volume and Open Interest for the SP contract were deleted. The Equity Management settings are not shown because they are the base systems settings. The EST-PolarConfidence-Weighted settings are not shown because they are the same as those listed below.

Sp_EST-Confidence-Weighted Data Settings
If you are trying this yourself then don’t forget to set the Trading Delay parameter to zero (the default value is 1). The parameter ranges for the adapted values have not been optimized. It is possible that longer Lookback periods may work better. A Confidence Threshold of 10% was used simply because it seems reasonable.

Sp_EST-Confidence-Weighted Bots And Swarm Settings
Ensemble Signal Trader Systems Performance
Screen images of the equity curves and hypothetical trade statistics for the base systems follow. Note that the master system equity curves are generally more consistent then the best base system equity curve. ScriptBot EST-PolarConfidence-Weighted produced the best result. However, only one trading simultion per system was run. Ideally, a minimum of ten runs per system would be run and the average results analyzed. As I mentioned earlier, this is a quick bit of work done to see if further research is warranted.

Sp_EST-Confidence-Weighted Price Signal Equity Charts

Sp_EST-Confidence-Weighted Trade Statistics
For the readers interest, an image of the trade bots appears below.

Sp_EST-Confidence-Weighted Parameter Scatter Chart

Sp_EST-PolarConfidence-Weighted Price Signal Equity Charts

Sp_EST-PolarConfidence-Weighted Trade Statistics

Sp_EST-PolarConfidence-Weighted Parameter Scatter Chart
Conclusion
The confidence based EST ScriptBots were effective when applied to the two base systems over the period from 01/02/2005 to 08/08/2009. Further research will include running the systems from 1982 and including additional base systems. Also, while writing this article it occured to me that EST ScriptBots with multiple adapted lookback periods might be more effective in the long term. For example, lookback period 1 adapted between 20 and 60 trading days, lookback period 2 between 60 and 250 trading days and lookback period 3 between 250 and 500 trading days. The confidence weighting from the three lookback periods would then be averaged to form the signal.
Regards,
James




















