The Ehlers Instantaneous Trendline strategy is proposed by John Ehlers in his book “Cybernetic Analysis for Stocks and Futures”. It utilizes technical indicators to identify real-time trends of stocks/futures and open positions when trends reverse.
The core of this strategy is calculating the Instantaneous Trendline (IT). The formula for IT is:
it := (a-((a*a)/4.0))*src+0.5*a*a*src[1]-(a-0.75*a*a)*src[2]+2*(1-a )*it[1]-(1-a )*(1-a )*it[2]
where src is the price, a is a smoothing factor, default to 0.07. This formula is a second order filter that can smooth the price and generate trends.
Another key indicator is the lag line, calculated by:
lag = 2.0 * it - nz(it[2])
The lag line lags IT line by one bar. When price crosses above lag line, it signals an upside breakout, go long. When price crosses below lag line, it signals a downside breakout, go short.
In addition, the strategy sets stop loss orders to control risks.
The advantages of this strategy include:
There are also some risks with this strategy:
These risks can be alleviated by:
This strategy can be further optimized in the following aspects:
Overall, the Ehlers Instantaneous Trendline strategy utilizes technical indicators to identify real-time trends in stocks/futures and open positions when trends reverse. It has the advantages of effective noise filtering, high parameter tuneability, clear signal generation logic, and incorporated risk control. With further optimization on parameter selection, signal filtering, position sizing and stop loss tuning, this strategy can achieve even better performance. The clear code structure also makes it easy to understand and modify. In summary, this is an efficient trend following system worth testing and improving.
/*backtest start: 2022-12-13 00:00:00 end: 2023-12-19 00:00:00 period: 1d basePeriod: 1h exchanges: [{"eid":"Futures_Binance","currency":"BTC_USDT"}] */ //@version=3 strategy("Ehlers Instantaneous Trendline Strategy", shorttitle = "Ehlers Instantaneous Trendline Strategy", overlay = true, default_qty_type = strategy.percent_of_equity, default_qty_value = 100.0, pyramiding = 1, backtest_fill_limits_assumption = 1) src = input(hl2, title="Source") a = input(0.07, title="Alpha", step=0.01) fr = input(false, title="Fill Trend Region") it = na if (na(it[2]) or na(it[1])) it := (src + 2 * src[1] + src[2]) / 4.0 else it := (a-((a*a)/4.0))*src+0.5*a*a*src[1]-(a-0.75*a*a)*src[2]+2*(1-a )*it[1]-(1-a )*(1-a )*it[2] lag = 2.0 * it - nz(it[2]) rngFrac = input(0.35) revPct = input(0.015) stopType = input(title="Stop type", defval = "stop-order", options = ["stop-order", "market-order", "None"]) diff = input(0.5, title = "Spread") LongPrice(p) => LongPrice = diff == 0 ? p : floor(p / diff) * diff ShortPrice(p) => ShortPrice = diff == 0 ? p : ceil(p / diff) * diff strategy.cancel_all() reverseTrade = false if stopType == "market-order" if strategy.position_size > 0 and close < strategy.position_avg_price * (1 - revPct) strategy.order("StopLoss open short", strategy.short, 2 * strategy.position_size, limit = close - 2 * diff) reverseTrade := true if strategy.position_size < 0 and close > strategy.position_avg_price * (1 + revPct) strategy.order("StopLoss open long", strategy.long, -2 * strategy.position_size, limit = close + 2 * diff) reverseTrade := true if lag > it and not reverseTrade price = LongPrice(max(close - (high - low) * rngFrac, low)) if strategy.position_size <= 0 strategy.order("Open long", strategy.long, strategy.equity / price - strategy.position_size, limit = price) if stopType == "stop-order" strategy.order("StopLoss open long", strategy.short, 2 * strategy.equity / price, stop = ShortPrice(price * (1 - revPct))) else if stopType == "stop-order" strategy.order("StopLoss open short", strategy.short, 2 * strategy.position_size, stop = ShortPrice(strategy.position_avg_price * (1 - revPct))) if lag < it and not reverseTrade price = ShortPrice(min(close - (high - low) * rngFrac, high)) if strategy.position_size >= 0 strategy.order("Open short", strategy.short, strategy.equity / price + strategy.position_size, limit = price) if stopType == "stop-order" strategy.order("StopLoss open short", strategy.long, 2 * strategy.equity / price, stop = LongPrice(price * (1 + revPct))) else if stopType == "stop-order" strategy.order("StopLoss open long", strategy.long, -2 * strategy.position_size, stop = LongPrice(strategy.position_avg_price * (1 + revPct))) itPlot=plot(it, color=red, linewidth=1, title="Trend") lagPlot=plot(lag, color=blue, linewidth=1, title="Trigger") fill(itPlot, lagPlot, it < lag ? green : red, transp=70) // === Backtesting Dates === testPeriodSwitch = input(false, "Custom Backtesting Dates") testStartYear = input(2018, "Backtest Start Year") testStartMonth = input(9, "Backtest Start Month") testStartDay = input(1, "Backtest Start Day") testStartHour = input(0, "Backtest Start Hour") testPeriodStart = timestamp(testStartYear,testStartMonth,testStartDay,testStartHour,0) testStopYear = input(2018, "Backtest Stop Year") testStopMonth = input(12, "Backtest Stop Month") testStopDay = input(14, "Backtest Stop Day") testStopHour = input(14, "Backtest Stop Hour") testPeriodStop = timestamp(testStopYear,testStopMonth,testStopDay,testStopHour,0) testPeriod() => time >= testPeriodStart and time <= testPeriodStop ? true : false isPeriod = testPeriodSwitch == true ? testPeriod() : true // === /END if not isPeriod strategy.cancel_all() strategy.close_all()