Way of the Turtle

Discussion in 'Philosophy and Strategy' started by 大地飞鹰, May 27, 2007.

  1. Tharp’s Thoughts

    Way of the Turtle, Way to Go

    By
    Van K. Tharp

    I recently wrote a foreword for a book that I think is one of the top five trading books ever written. It’s Curtis Faith’s new book, Way of the Turtle. Curtis was one of the more successful traders in Richard Dennis’ experiment to see if he could train good traders. And since I was part of the selection process, but never knew what happened once they started training, I was fascinated to get these insights.

    So why do I believe that it is one of the five best trading books ever written? First, it paints a very clear picture of what is necessary for trading success. Curtis says in very concise terms that it’s not about the trading system. Instead, it’s about the trader’s ability to execute the trading system. During the initial training period, Curtis earned almost three times as much as the others combined, yet they’d all been taught to do the same thing.

    Think about it: Ten or so people who had all been taught a certain set of rules, including fixed position sizing rules, all produced different results. The answer as to why is, of course, that trading psychology produced the differences in the results. And Curtis really brings this point home in his book.

    The second really fascinating aspect of Way of the Turtle is that it probably has the most lucid description of how some of the principles of behavior finance apply to and influence trading that I’ve ever read. Curtis even goes into a lengthy discussion of support and resistance and why these exist because of inefficiencies in our decision making. It is must read material.

    The third aspect of the Way of the Turtle that I really like is Faith’s emphasis on game theory and using it to explain how a trader should think. For example, he suggests that you concentrate on the present trading, forgetting the past and the future. Why should you do this? You should know from your historical testing that you will probably be wrong most of the time in your trading. But you should also know that some of your gains will be huge, which will result in a positive expectancy. Curtis tells the reader why they must understand and have confidence in the expectation of their system. And it’s this confidence that will make them long term winners.

    Other excellent topics along the same lines include:

    How the Turtles were trained and what they actually learned.

    The real “secrets” of the Turtles (and I’ve already given you lots of clues).

    An excellent discussion of the problems involved with system development and why people make mistakes in their system development because they don’t understand basis statistical principles involved in sampling theory.

    A superb discussion of why most systems fail to perform adequately. And even though most good systems are dropped for psychological reasons, there are also many bad systems out there that look good at first glance. So if you want to know why and how to spot them, then you must read this book.

    And lastly, there is an interesting discussion of robust measures of systems. And if you understand this material, you will go a long way toward being able to design a long-term profitable system for yourself that will work.
     
  2. TAMING THE TURTLE MIND

    By Curtis Faith

    Excerpted from the Newly Released Way of the Turtle

    Human emotion is both the source of opportunity in trading and the greatest challenge. Master it and you will succeed. Ignore it at your peril.

    To trade well you need to understand the human mind. Markets are comprised of individuals, all with hopes, fears and foibles. As a trader you are seeking out opportunities that arise from these human emotions. Fortunately, some very smart people—behavioral finance pioneers—have identified the ways that human emotion affects one’s decision-making process. The field of behavioral finance—brought to popular attention in Robert Shiller’s fascinating book, now in its Second Edition, titled Irrational Exuberance and greater details of which were published by Hersh Shefrin in his classic Beyond Greed and Fear—helps traders and investors understand the reasons why markets operate the way they do. Just what does make prices go up and down? (Price movements can turn an otherwise stoic individual into a blubbering pile of misery.)



    Behavioral finance is able to explain market phenomena and price action by focusing on the cognitive and psychological factors that affect buying and selling decisions. The approach has shown that people are prone to making systematic errors in circumstances of uncertainty. Under duress, people make poor assessments of risk and event probabilities. What could be more stressful than winning or losing money? Behavioral finance has proved that when it comes to such scenarios, people rarely make completely rational decisions. Successful traders understand this tendency and benefit from it. They know that someone else’s errors in judgment are opportunities, and good traders understand how those errors manifest themselves in market price action: The Turtles knew this.

    Emotional Rescue

    For many years economic and financial theory was based on the rational actor theory, which stated that individuals act rationally and consider all available information in the decision-making process. Traders have always known that this notion is pure bunk. Winning traders make money by exploiting the consistently irrational behavior patterns of other traders. Academic researchers have uncovered a surprisingly large amount of evidence demonstrating that most individuals do not act rationally. Dozens of categories of irrational behavior and repeated errors in judgment have been documented in academic studies. Traders find it very puzzling that anyone ever thought otherwise. The Turtle Way works and continues to work because it is based on the market movements that result from the systematic and repeated irrationality that is embedded in every person. How many times have you felt these emotions while trading?

    • Hope: I sure hope this goes up right after I buy it.

    • Fear: I can’t take another loss; I’ll sit this one out.

    • Greed: I’m making so much money, I’m going to double my position.

    • Despair: This trading system doesn’t work; I keep losing money.

    With the Turtle Way, market actions are identified that indicate opportunities arising from these consistent human traits. This chapter examines specific examples of how human emotion and irrational thinking create repetitive market patterns that signal moneymaking opportunities.

    People have developed certain ways of looking at the world that served them well in more primitive circumstances; however, when it comes to trading, those perceptions get in the way. Scientists call distortions in the way people perceive reality cognitive biases. Here are some of the cognitive biases that affect trading:

    • Loss aversion: The tendency for people to have a strong preference for avoiding losses over acquiring gains

    • Sunk costs effect: The tendency to treat money that already has been committed or spent as more valuable than money that may be spent in the future

    • Disposition effect: The tendency for people to lock in gains and ride losses

    • Outcome bias: The tendency to judge a decision by its outcome rather than by the quality of the decision at the time it was made

    • Recency bias: The tendency to weigh recent data or experience more than earlier data or experience

    • Anchoring: The tendency to rely too heavily, or anchor, on readily available information

    • Bandwagon effect: The tendency to believe things because many other people believe them

    • Belief in the law of small numbers: The tendency to draw unjustified conclusions from too little information.

    Although this list is not comprehensive, it includes some of the most powerful misperceptions that affect trading and prices.

    In another edition of this newsletter, we'll look at each cognitive bias in greater detail.
     
  3. TAMING THE TURTLE MIND

    Part Two

    by Curtis Faith

    Excerpted from the Newly Released Way of the Turtle



    In part of this excerpt from the excellent new book by Curtis Faith, we detailed some of the most powerful misperceptions that affect trading and prices. If you missed part one, click here.

    This week we'll look at each cognitive bias in greater detail.

    People who are affected by loss aversion have an absolute preference for avoiding losses rather than acquiring gains. For most people, losing $100 is not the same as not winning $100. However, from a rational point of view the two things are the same: They both represent a net negative change of $100. Research has suggested that losses can have as much as twice the psychological power of gains. In terms of trading, loss aversion affects one’s ability to follow mechanical trading systems because the losses incurred in following a system are felt more strongly than are the potential winnings from using that system. People feel the pain of losing much more strongly when they follow rules than they do when they incur the same losses from a missed opportunity or by ignoring the rules of the system. Thus, a $10,000 loss is felt as strongly as a $20,000 missed opportunity. In business, sunk costs are costs that already have been incurred and cannot be recovered. For example, an investment that already has been spent on research for a new technology is a sunk cost. The sunk cost effect is the tendency for people to consider the amount of money that already has been spent—the sunk costs—when making decisions.

    Say the ACME Company has spent $100 million developing a particular technology for building laptop displays. Now suppose that after spending this money it becomes obvious that an alternative technology is much better and more likely to produce the desired results in the required time frame. A purely rational approach would be to weigh the future costs of adopting the new technology against the future expense of continuing to use the developed technology and then make a decision solely on the basis of future benefits and expenditures, completely disregarding the amount of money that already has been spent.

    However, the sunk cost effect causes those who make this decision to consider the amount of money previously spent and view it as a waste of $100 million if a different technology is used. They may choose to continue with the original decision even if it means spending two or three times as much in the future to build the laptop displays. The sunk cost effect leads to bad decision making that often is heightened in group situations.

    How does this phenomenon influence trading? Consider the typical new trader who initiated a trade with the expectation of winning $2,000. At the time the trade first was entered, he decided that he would exit the position if the price dropped to the point where a $1,000 loss would be incurred. After a few days, the trade’s position is at a $500 loss. A few more days pass and the loss grows to over $1,000: More than 10 percent of the trading account. The value of that account has dropped from $10,000 to less than $9,000.

    This also happens to be the point where the trader previously decided to exit.

    Consider how cognitive biases might affect the decision whether to keep true to the prior commitment to get out at a $1,000 loss or to keep holding the position. Loss aversion makes it extremely painful for the trader to consider exiting the position because that would make the loss permanent. As long as he does not exit, he believes there is a chance that the market will come back and turn the loss into a win. The sunk cost effect makes the decision not one of deciding what the market is likely to do in the future but one of finding ways to avoid wasting the $1,000 that already has been spent on the trade. So, the new trader continues to hold the position not because of what he believes the market is likely to do but because he does not want to take a loss and waste that $1,000. What will he do when the price drops even more and the loss increases to $2,000? Rational thought dictates that he will exit. Regardless of his earlier assumption about the market, the market clearly is telling him that he was wrong, since it is far past the point at which he originally decided to exit. Unfortunately, both biases are even stronger at this point. The loss he wishes to avoid is now larger and even more painful to consider. For many, this kind of behavior will continue until the trader loses all his money or finally panics and exits with a loss of 30 to 50 percent of his account, perhaps three to five times what he had planned.

    I worked in Silicon Valley during the height of the Internet craze and had many friends who were engineers and marketers for hightech companies. Several of them were worth millions from stock options on companies that recently had gone public. They watched the prices go up day after day during late 1999 and early 2000. As prices started to drop in 2000, I asked many of them when they were going to sell their stock. The reply was inevitably something along the lines of the following: “I’ll sell if it gets back up to $X,” a price that was significantly higher than the level at which the market was when I asked. Almost every single one of my friends who was in this position watched the price of his or her stock drop to a tenth or even a hundredth of its previous value without selling the shares. The lower it dropped, the easier it was for them to justify waiting. “Well I’ve already lost $2 million. What’s a few more hundred thousand?” they would say.

    The disposition effect is the tendency for investors to sell shares whose price is increasing and keep shares that have dropped in value. Some say that this effect is related to the sunk cost effect since both provide evidence of people not wanting to face the reality of a prior decision that has not worked out. Similarly, the tendency to lock in winning trades stems from the desire to avoid losing the winnings. For traders who exhibit this tendency, it becomes very difficult to make up for large losses when winning trades are prematurely cut short of their potential.

    Outcome bias is the propensity to judge a decision by its outcome rather than by the quality of the decision at the time it was made. Much of life is uncertain. There are no right answers to many of the questions that involve risk and uncertainty. For this reason, a person sometimes will make a decision that he considers rational and that appears to be correct, but as a result of unforeseen and unforeseeable circumstances that decision will not lead to the desired outcome. Outcome bias causes people to put too much emphasis on what actually occurred rather than on the quality of the decision itself.

    In trading, even a correct approach can result in losing trades, perhaps a few in a row. These losses can cause traders to doubt themselves and their decision process, and they then evaluate the approach they have been using negatively because the outcome of that approach has been negative. The next bias makes this problem particularly acute.

    Recency bias is the tendency for individuals to place greater importance on more recent data and experience. A trade that was made yesterday weighs more heavily than do trades from last week or last year. Two months of losing trades can count as much as or more than the six months of winning trades that happened previously. Thus, the outcome of a series of recent trades will cause most traders to doubt their method and decision-making process. Anchoring is the tendency for people to rely too heavily on readily available information when making a decision involving uncertainty. They may anchor a recent price and make decisions on the basis of how the current price relates to that price. This is one of the reasons my friends had such difficulty selling their stocks: They were anchoring on the recent highs and comparing the current price with those highs. After they made that comparison, the current price always looked too low.

    The observation that people often believe things because many other people believe them is known as the bandwagon effect or the herd effect. The bandwagon effect is partially responsible for the seemingly unstoppable increase in prices at the end of a price bubble.

    People who fall under the spell of the law of small numbers believe that a small sample closely resembles the population from which it is drawn. The term is taken from the statistical law of large numbers, which shows that a large sample drawn from a population does closely resemble the population from which it is taken.

    This law is the basis of all polling. A sample of 500 taken randomly from a larger population can give very good estimations for a population of 200 million or more people. In contrast, very small samples do not reveal much about the underlying population. For example, if a trading strategy works four times out of a test of six times, most people would say the strategy is a good one, whereas statistical evidence indicates that there is not enough information to draw that conclusion with any certainty. If a mutual fund manager outperforms the indexes three years in a row, he is considered a hero. Unfortunately, a few years of performance says very little about what the long-term expectations might be. Belief in the law of small numbers causes people to gain and lose too much confidence too quickly. When combined with the recency effect and outcome bias, it often results in traders abandoning valid approaches just before those approaches start working again. Cognitive biases have a profound effect on traders because if a trader is not influenced by them, almost every bias creates opportunities to make money. In the following chapters, as specific aspects of the Turtle Way are explored, you will see how avoiding these biases can provide you with a significant advantage in trading.
     
  4. My points:
    <Way of the Turtle>,作者Curtis Faith,可能是成功的Turtle。该书由Van K. Tharp作序,从介绍来看,很可能是类似于<Trade Your Way to Financial Freedom >,对交易心理和行为金融有独特的深入描述。除此而外,以下两部分内容可能很精彩:
    A superb discussion of why most systems fail to perform adequately. And even though most good systems are dropped for psychological reasons, there are also many bad systems out there that look good at first glance. So if you want to know why and how to spot them, then you must read this book.

    And lastly, there is an interesting discussion of robust measures of systems. And if you understand this material, you will go a long way toward being able to design a long-term profitable system for yourself that will work
     
  5. 好文! 谢谢!
     
  6. 我买了一本, 很不错. 交易系统的所有方面都涉及了. 唯一的缺点是海龟的故事讲得太少了.
     
  7. 交易系统所有方面都涉及的书不少啊,有没有什么独到之处?
     
  8. 交易系统讲得全面的书不多啊. 你列出来一些, 如果我看过的话, 可以评论一下.

    WOTT对很多概念都有独到的分析, 特别是对优化,测试和系统的鲁棒性有很多独到的评论. 我觉得所有系统交易员都应该买一本.
     
  9. 有没有电子版?呵呵
     
  10. 是啊,有没有电子版?
     
  11. 扫描上传吧,大家一块来读要快些全面些
     
  12. 恩,最好一天扫一小节贴上来,大家边读边讨论
     
  13. 不扫描,拍照也行,当然要拍清楚哦。
     
  14. 您直接说吧,怎么跟Amazon交流交流。我查过Amazon在中国的代理,他们没这本书,发了个email也没人睬。Amazon倒是睬了,但是我搞不懂这种跨国采购,怎么打款,怎么过关,怎么交税,比我去一趟都麻烦。
    这段时间你的那位朋友的书正好打折,卖价+税+邮费可能在人民币300元左右,我可以接受。
     
  15. 可以用信用卡在AMAZON直接购买邮寄回来,快递直接送上门,貌似不用自己过关交税,查查EMULE,0DAY之类的资源上有没有电子版下载,下了打印比较方便
     
  16. 很好奇,老Van认为的top five trading books是哪5本?
     
  17. 要不就这样,大家一起凑钱,一人出一点,由一个人负责具体操作去买一本,然后再拿来复印装订,一人一份影印版,原本就放在具体操作的人那。
     
  18. 只要10以上就可以找个有经验的一起购买,或者委托给专业书商。

    报个名吧。

    我,第一个。