Alan Farley 2015年8月21日
交易員和技術人員可以通過建立準確預測重要高點和低點的循環研究深入了解市場行情。相對強度指標，包括推斷統計學和王爾德相對強度指數是提供了創建循環學習的流行方式。當指標在超買和超賣水平徘徊時，分析人士預測價格將向相反方向移動。
非趨勢價格擺動指標（DPO）去除相對強度中的動量，呈現一個更簡單的視角估計從高點到低點的價格週期寬度。該指標旨在降低特定週期長度中長期趨勢的影響，專註於短期的波動。該指標在最基本的調查水平把收盤價格和移動平均數進行比較，尋找乘離率的關系。
非趨勢價格擺動指標為交易員和技術人員提供一個優秀的時間界定工具，但是應當和價格圖表分析和其他提供進出點的指標一起使用，將會為交易決定提供一個完美的互補。
非趨勢價格擺動指標應用
First Solar Inc的買賣信號
正如在上圖中看到的，First Solar Inc在2015年3月和2015年8月的一系列的高點和低點中徘徊。相對高點為圖中所示的1、3、5、8，相對低點則為2、4、6、7、9。設置非趨勢價格擺動指標能捕捉到9個高點和低點中的6個。正如你所見，1點和A點對應，2點和B點對應，3點和C點對應，4點和D點對應，6點和F點對應，8點和H點對應。該指標嚴重錯誤地把5點和F點對應，7點和G點沒展示出相關性。
乍一看，該指標在股票集中在自2014年中的一個狹窄的交易區間和2014年10月到15年8月趨勢長度擴展時非常準確。值得註意的是，延遲指標到7或者增加到28對整體結果幾乎沒有影響。更短的設定通常切掉更多高點和低點並增加錯誤信號。更長的設定則產生更少的信號，但是準確性不變。
與移動平均數趨同和趨異的例子
iShares20+年債券ETF買賣信號
在上面圖表中，iShares 20+ Year Treasury Bond ETF在2014年呈現出穩定上升的趨勢，終於在2015年初封頂。在2015年中期出現支撐並開始校正。非趨勢價格擺動指標穿過2014年小波浪的高點和低點，與價格上升中波動大致匹配。在第三個圖中，你可以看見一個移動平均數的柱狀圖。她幾乎沒有超出這期間的基準線，沒有出現明確的買入和賣出信號。這個圖表看起來最適合短期策略，對其長期來說信號混淆和不可靠。
該指標能更好的預測2014年9月到2015年8月的價格運動，通過逆轉點提供有效的信號。在這期間模式和趨勢延長到更長的週期，表明該指標組合更適合這種價格環境。另外，二級乘離率移動平均值為5、6、7點增加更大的可靠性。
乘離率的移動平均值以三種方式出現：
- 高點或者低點的直方圖。
- 基準線的直方交叉。
- 上升或下降直方圖呈現出更高的低點和更低的高點。
上面的例子呈現出一系列第一種信號的例子，更多的非趨勢價格擺動指標使用這些信號時有相關性。雖然引入了一些主觀性，但是也能為交易員構建更複雜的信號機制提供參考。
總結
非趨勢價格擺動指標為循環分析提供一個簡單的方法。它排除長期趨勢的動量而定義一個短期週期並改善進入市場時機。
Detrended Price Oscillator Trading Strategies
By Alan Farley | August 21, 2015
Traders and technicians can see deeply into the mind of the market by creating cycle studies that can reliably predict significant highs and lows. Relative strength indicators, including stochastics and Wilder’s relative strength index (RSI), present one popular approach to creating cycle studies. When indicators roll over at overbought and oversold levels, analysts predict prices will begin heading in the opposite direction.
The detrended price oscillator (DPO) removes momentum from the relative strength equation, presenting a simpler view that estimates the length of price cycles from peak to peak, or from trough to trough. The indicator seeks to reduce the impact of long-term trends in defining cycle length, focusing instead on short-term price swings. At the most basic level of inquiry, the detrended price oscillator just compares closing price to a moving average, looking at convergence-divergence relationships.
The detrended price oscillator offers traders and technicians an excellent market timing tool but should be used in conjunction with price pattern analysis and other indicators that provide entry and exit signals. Since it strips out momentum from the analysis, a momentum indicator, like an MACD histogram (moving average convergence divergence), provides a perfect complement by adding reliability to trading decisions.
The Detrended Price Oscillator in Action
Buy and Sell Signals for First Solar Inc
As you can see in the chart above, First Solar Inc (FSLR) grinds through a series of highs and lows between March 2014 and August 2015. Relative highs are posted at dates corresponding to points 1, 3, 5 and 8 while relative lows are posted at dates corresponding to points 2, 4, 6, 7 and 9. Setting the detrended price oscillator to 21-periods does a good job of capturing six of the nine highs and lows within a few price bars. As you can see, Point 1 in the price history corresponds to Point A in the detrended price oscillator chart, Point 2 corresponds to Point B, Point 3 corresponds to Point C, Point 4 corresponds to Point D, Point 6 corresponds to Point F and Point 8 corresponds to Point H. The detrended price oscillator misses badly by corresponding Point 5 in the price chart with Point F. Finally, Point 7 and Point G show no correlation at all.
At a glance, the indicator showed greater accuracy when the security was bound up in a narrow trading range through the middle of 2014 and misfired when trend lengths expanded between October 2014 and August 2015. Notably, reducing the indicator setting to 7 or increasing it to 28 had little effect on overall results. Shorter settings tended to carve out more peaks and valleys, adding false signals to the mix. Longer settings produced fewer signals, but with equal accuracy.
An Example With Moving Average Convergence and Divergence
iShares 20+ Year Treasury Bond ETF Buy and Sell Signals
As you can see in the chart above, the iShares 20+ Year Treasury Bond ETF (TLT) ticks higher in a steady uptrend throughout 2014, finally topping out in early 2015. It then entered a correction that found support in the middle of 2015. The detrended price oscillator cuts through small waves of highs and lows into the third quarter of 2014, roughly matching channeled price swings within the uptrends. In the third chart, you can see a MACD histogram. It barely stretches above or below the zero line during this period, issuing few distinct buy or sell signals. This side of the chart looks best suited to short-term strategies, with mixed or unreliable signals for longer-term strategies.
The indicators do a better job of predicting price action between September 2014 and August 2015, with reversals at points 2-B-a, 3-C-b, 5-E-f, 6-F-g and 7-G-g providing valid signals. Patterns and trends stretch into longer cycles during this time, suggesting the indicator combination is better suited to this type of price environment. In addition, secondary moving average convergence divergence signaling added greater reliability to price turns at points 5, 6 and 7.
Moving average convergence divergence signaling comes in three varieties:
Histograms turn at high or low extremes.
Histograms cross their zero lines.
Rising or falling histograms print a higher low or a lower high.
The above example places a line over the first type of signal (histograms turn at high or low extreme), with much greater detrended price oscillator correlation when using a mix of these signals. While this introduces subjectivity, it also serves as a starting point for the trader or technician to build more complex signaling mechanisms as part of a back-tested systems strategy that uses both indicators.
The Bottom Line
The detrended price oscillator presents a simple approach to cycle analysis. It removes momentum and long-term trends from the calculation while defining a short-term cycle length that can improve market timing.
本文翻譯由兄弟財經提供
文章來源：http://www.investopedia.com/articles/active-trading/082115/detrended-price-oscillator-trading-strategies.asp