預測未來最好的方法是對歷史有一個全面的了解，著名的交易專家W.D. Gann在金融市場有50多年的經驗，他對迄今為止一百多年前的數據都有所研究。最令他滿意的發現就是歷史會重複，歷史走勢是未來價格走勢最好的預測者。他在過去半個多世紀對時間週期的預測證明是正確的，因為這些預測是基於人類的本性，而這是不變的。
Gann是一個複雜的人。他在大蕭條時期以$5,000售出他的碩士課程——即使在今天也是一筆巨款。人們付了款之後發現，仍然有很多不理解的地方。就像Gann在你的咖啡桌上扔了一個由1000塊零散部分組成的智能拼圖，你需要在沒有原圖參照的情況下將它拼在一起。很顯然，今天的這一代交易者都希望從一個很昂貴的交易課程中得到很多，這也就很容易理解為什麼很多人認為他的作品神秘而迷惑。
我們不能在一篇文章裡涵蓋Gann的種種神秘性，但是我們卻可以將一些拼圖部分成功的組合到一起。
對Gann而言，最重要也是最有價值的發現是價格與時間可以構成正方形。意思是，同等數量的價位對應同等的時間週期，因此，準確地預測趨勢中的重要變化是有可能的。當然，各種不同的情況是存在的。我們下面將會看一些宏觀的以及適合每日交易的例子。
崩盤事件
1987年崩盤之前，道瓊斯工業指數的最高點和最低點分別在2, 746.6和1, 638.3，波動範圍在1, 108.3個點。而從1987.8.25至2008.11.21共1,108.4週。我們需要忽視的是正在研究道瓊斯指數的頂部（納斯達克指數在1987.10月達到最高點，比道瓊斯指數晚了2個月）並且納斯達克指數在那一日最終達到了底部。這一市場變革是我們必須做的最複雜調整之一，因為Gann主要研究道瓊斯指數以及標普500.
毫無疑問的是，從1987年到2008.11.21牛市的底部與交易範圍之間行成了一個方形。過去幾年中市場積累的悲觀情緒導致的每一次抛售所顯示的熊市底部重要的週期性以及其與前期高點之間的關系都被誤解。
1987年道瓊斯指數的高點在整個世紀中都被認為有重要意義，是1989年以後牛市的開始。1108.49這個數字也很關鍵，因為納斯達克指數在2002年的熊市達到了該價位。
2008年奈斯達克100的低點不是一個隨機的軸點，而是歷史作用於長期市場走勢的結果。當前的投資以及交易決策應該考慮到這一點。所以，每一次市場抛售不會導致更進一步的熊市低點。既然這一低點如此重要，那麼如果想要擊穿它勢必需要強有力的幹預手段。
下面是一個小範圍的但是同等重要的例子。標普500在1576.09 至666.79 之間波動，幅度達到 909.30點，在2007.10.11達到最高點。如果我們從2007.10.11至2010.4.26計算，那麼我們將會得到928日，很顯然，不成立。
然而，市場交易從來不是簡單的事，你需要不斷地挖掘市場試圖隐藏的真正目的。當我們從2007.10.31至2010.4.26計算納斯達克指數天數時，結果是908日，結果相差1（正負差1是可以接受的）。這中關系標志重要的交易滞後性。
Gann的一些材料對於現代的交易者來說很神秘。其中一個原因是並不是所有的資料都十分清楚。或許他希望自己的學生進行自己的研究。這種理念有幾種變體。波動範圍在長期之後會呈正方形。對於道瓊斯以及納斯達克100指數，1987年以來的時間與交易範圍呈正方形。別的情況下，交易者需要從極低點開始計算，交易者也有可能得到1，108的波動範圍，並且與最低點、最高點之間都呈正方形。對所有可能性都持開放態度，這一點很重要。
誠然，這一點很具有迷惑性，Gann也從來沒有預見到自己的方法適用於高速運轉的網絡世界。因此，現代交易者探索這些技術將會面臨更大的挑戰。
21世紀的Gann
短期交易者需要對掌握小數點並對其進行調整。2007~2009年道瓊斯處於熊市，高點為14,198 低點是 6,470，波幅7,728點。從2009.3.6的底部至2010.8.27，當道瓊斯指數於8月份之後在9,937位置抛售，實現了重要的反轉，很少人意識到其距離底部已經達到77週。
安進股價在8.27號達到低點，65日之後達到另外一個低點。10.19號達到58.74的高點，11.29號的低點為52.19，波動範圍在6.55。交易者都需要適應五位數的道瓊斯指數，四位數的標普500指數，小數點後2~4位數的外匯報價。
7700/77 與65/6.55的意義相當。這既可以單獨的也可以結合別的工具使用。正如我們所看到的，長期波動範圍的計算很難與別的方法結合使用。然而，短期交易是關於價格波動的確定性以及給交易者提供足夠的交易證據。交易的可能性越大，盈利的可能性也就越大。
比如，安進股價以及安德魯分叉線。價格在這個特定形態的下半部分反轉，這在技術層面給了交易者更多的交易信心。這是交易者入場的一個很好的時機，但是接下來價格的小幅波動挑戰了交易者的信心。最終，價格形成缺口並上移至通道的中部，使之成為一個很好的震蕩交易。
另外一個變體是時間與價格在相同的位置形成正方形。KBW銀行指數在四月份達到頂部是一個很好的例子。從2009.3月的底部到58.81的價格最高點大約是59週。從2009.3.6至2010.4.21，共58.71週) 這種方法給了交易者很高的時間精準度。如果方形關系可以被一個關鍵部門或者重要的市場領導者識別，那麼這將會是一個很大的優勢，因為他可以利用該信息獲得很多交易機會。
我們大多數人對於Gann的方法都很陌生，因此，在學習時，我們需要呈開放的態度。那些首次練習這些方法的交易者需要足夠的耐心來信賴這種模式。Gann把這種波動範圍和時間呈正方形的交易方法視為他最重要的發現，這種方法即使在今天也毫不遜色。
W.D. Gann's master forecasting methods
The best way to predict the future is to have an understanding of the past, noted master trader W.D. Gann who had more than 50 years of experience in financial markets and did research dating back hundreds of years. What he found to his satisfaction was that history repeats, and the past is the best predictor of future prices. His forecasts of time cycles over a half century proved to be accurate because those cycles are based on human nature, which does not change.
Gann was a complex individual. He sold his master course during the Great Depression for $5,000 — a small fortune in today’s dollars. People paid the price, but found a lot was left to interpretation, perhaps akin to Gann dropping a 1,000-piece jigsaw puzzle on your coffee table and leaving you to assemble it without a picture. Needless to say, today’s generation of traders would expect more out of an expensive trading course, so it’s understandable why so many find his work mysterious and confusing.
We can’t conquer Gann’s mysteries in one article, but we can put a few practical pieces of that puzzle together.
According to Gann himself, one of his most important and valuable discoveries was that price squares with time. This means that it’s possible to forecast important changes in a trend with greater accuracy because an equal number of price points balance an equal number of time periods. There are variations, though. We’ll look at some macro examples and then one that is applicable to everyday trading.
Crash matters
The high in the Dow Jones Industrial Average before the 1987 crash came in at 2,746.6 and bottomed out at 1,638.3, for a range of 1,108.3 points (see "Crashed out"). When we take the time from Aug. 25, 1987, to Nov. 21, 2008, it comes out to 1,108.4 weeks. We must overlook that we are working with a Dow top (the Nasdaq 100 topped in October 1987, two months later than the Dow) and an ultimate Nasdaq 100 bottom on that date. This market evolution is one of the complex adjustments we must make because Gann dealt mostly with the Dow and S&P 500.
It is beyond doubt that the range from the 1987 sequence has squared time to the point where the market traced out one of its bear market bottoms on Nov. 21, 2008. With all the bearish sentiment the past couple of years, each sell-off demonstrates how much the cyclical importance of the bear market bottom is misunderstood — as well as its ties to the cycle top of a generation earlier.
The 1987 high was recognized as an important top for the entire decade, until it was taken out in 1989 on the recovery that led to the bull market of the 1990s. The 1,108 number also appears to be critical because 1108.49 is also the low for the Nasdaq Composite in the bear market in 2002.
The 2008 Nasdaq 100 low is not just some random pivot, but a point in history tied into long-term market cycles. It should be put into context with current investment and trading decisions. Every market sell-off will not lead to new bear market lows. However, given that low is so important, it would take a powerful leg to violate and invalidate it.
The next example is of a smaller degree but no less significant. The S&P 500 bear market had a range of 1576.09 to 666.79 for 909.30 points, which topped on Oct. 11, 2007. If we take the number of calendar days from Oct. 11, 2007 to the April 26, 2010 high we get 928 days, so apparently it doesn’t work.
However, the market is never easy and it makes you dig as it attempts to conceal its true hand. When we take the Nasdaq top from Oct. 31, 2007 to April 26, 2010, we get 908 calendar days, which puts us off by one. (A margin of error of plus or minus one is acceptable.) The relationship marked an important trading leg down.
Much of Gann’s material is a mystery to modern day traders. One reason is that not all of Gann’s principles are clear. Perhaps the master wanted his students to do their own due diligence. There are several variations to this concept. The range will square over a long period of time. In the case of the Dow and Nasdaq 100, time squared with the range from the extreme high back in 1987 to a market bottom. In other instances, the trader might have to calculate from the extreme low. It also is possible a range such as 1,108 could have squared from either the top or bottom and terminated to create the top. It’s important to be open to all of the possibilities.
Granted, this can be confusing, and Gann never envisioned his methods to be used in a fast-paced Internet world. Given that, it is no doubt more challenging for modern traders to exploit these techniques.
21st century Gann
Shorter-term trading requires an adjustment and the manipulation of the decimal point. The Dow bear market of 2007-09 had a high of 14,198 to a low of 6,470, for a range of 7,728 points. From the bottom on March 6, 2009 to Aug. 27, 2010, when the Dow made an important turn after the August sell off at 9,937, few people realized that it was 77 weeks off the bottom.
Amgen had a low on that August turn and found another low 65 trading days later (see "Pitching in"). With a high on Oct. 19 at 58.74 and a low at 52.19, there was a range of 6.55. In a world with a five-digit Dow, four-digit SPX and either two to four digits to the right of the decimal on futures or forex, traders must adapt.
In the case of 7700/77 or 65/6.55, the meaning is the same. This can be used as a standalone technique or in combination with another tool. As we have seen, it would be hard to combine a long-term range calculation with any other method. However, shorter-term trading is about developing conviction about a move and the more evidence the trader can stack, the greater the probability he or she will get to the point of allowing a winner to run.
For example, the Amgen move is combined with an Andrew’s pitchfork. This particular pattern reversed right on the lower pitchfork line to give the trader more confidence in the overall technical condition. There was good evidence to take the initial trade, but with early congestion, it may have challenged the trader’s faith. Eventually, this move gapped through the midline right to the upper channel, making it a good swing trade.
Another variation is where time and price square in the same place. A great example of this was the April top in the KBW Bank Index (see "Banking on it"). The high since the March 2009 bottom came in at price point 58.81 in roughly 59 weeks. (From March 6, 2009 to April 21, 2010 it is exactly 58.71 weeks.) This method gives the trader a high degree of timing precision. If a square relationship can be identified on a key sector or important market leader, it can be a huge edge because the trader can leverage this information into many kinds of trading opportunities.
Gann’s techniques are so new to most of us that it is necessary to have an open mind as we approach them. For those practicing these methods for the first time, it will require practice and patience to learn to trust the pattern. Gann called the squaring the range with time method his most important discovery, and it is still as valuable today as it was in his era.
本文翻譯由兄弟財經提供
文章來源：http://www.fxstreet.com/education/technical/wd-ganns-master-forecasting-methods/2012/11/22/