Finance and economics | Buttonwood
财经板块 | 梧桐树专栏
Finance and economics | Buttonwood
When to sell your stocks
Poker provides investors with helpful guidance
Watch professionalsplay poker, and one of the first things to strike you is how often they fold when the game has barely begun. Rounds of Texas Hold’em, a popular variant, start with each player being dealt two cards and then deciding whether to bet on them. Amateurs are more likely to proceed than not, while pros fold immediately up to 85% of the time. Naturally this does not mean that high-stakes casinos are frequented by the timid. It is simply that most hands are too likely to lose to be worth betting on, and the pros are better at judging when this is the case.看行家玩牌，首先震惊你的就是他们经常很早就弃牌。德州扑克是一种流行的扑克牌玩法，每轮游戏开始时，每位玩家都会发到两张牌，然后决定是否下注。业余玩家更有可能继续下注，而专业玩家立即盖牌放弃的概率高达85%。当然这并不意味着动辄一掷千金的赌场是胆小者的天下，只是因为大多数牌都很可能会输，并不值得下注，而专业玩家更善于看清这一点。Investors usually dislike gambling comparisons. Yet at a recent conference held by Norges Bank Investment Management, which oversees Norway’s oil fund of $1.6trn, a packed hall sought to learn from a former poker pro. Annie Duke was there to talk about quitting decisions, a topic on which she wrote the book (“Quit: The Power of Knowing When to Walk Away”). Ms Duke argued that many factors stack the deck against people considering quitting, pushing them to act irrationally. That applies to poker players wondering whether or not to fold—and also to investors considering whether to exit a position.投资者通常不喜欢拿投资和赌博作比较。但是在挪威银行投资管理公司（该公司负责管理挪威1.6万亿美元的石油基金）最近举行的会议上，现场座无虚席，大家都想向一位前职业扑克玩家取经。安妮·杜克在会上谈到了“退出决策”，她曾以此主题写了《退出：知道何时离开的力量》一书。杜克女士认为人们考虑退出时会受到很多因素的干扰，促使他们做出不理智的行为。这一理论既适用于考虑是否弃牌的扑克玩家，也适用于考虑是否退出头寸的投资者。注释：
头寸：头寸是投资人自己对某项资产未来价值走势的判断。简单来说，就是站在哪方立场上看待这一资产，是看好它决定购买，还是不看好它想要卖出。
Selling out of a position is much harder to do well than buying into it. To see why, start with some now-famous biases popularised by Daniel Kahneman and Amos Tversky, two giants of behavioural science on whose work Ms Duke draws. People hate losses a lot more than they enjoy equivalent gains (“loss aversion”) but reserve a special loathing for crystallising a certain loss, even if the probable alternative is a greater one (“sure-loss aversion”).They also value things they own more than identical things they do not (the “endowment effect”). All this makes closing a losing position an absolute wrench. Already smarting from a paper loss, you must turn it into a certain one, while also letting go of an asset you value more than you would any equivalent alternative.卖出头寸比买入头寸更难做好。要了解原因，可以从一些著名的偏见开始。丹尼尔-卡尼曼（Daniel Kahneman）和阿莫斯-特沃斯基（Amos Tversky）两位行为科学巨匠的研究成果使这些偏见广为人知，杜克女士也借鉴了他们的研究。首先是“损失厌恶”——人们痛恨损失的程度远远超过享受同等收益的程度；其次是“确定损失厌恶”——人们更加厌恶确定的损失，即使不确定的损失或许金额更大。还有“拥有效应”——对于同样的东西，人们更看重自己已有的，而不是没有的。在上述因素的影响下，退出亏损的头寸成为了艰难的抉择。在已承受账面亏损的情况下，你必须将其变为确定的亏损，还要放弃你更看重的已拥有资产，而不是任何同等的替代品。Small wonder retail traders are bad at this. Alex Imas of the University of Chicago has studied the behaviour of those who set take-gain and stop-loss orders when they enter a trade. Although these are supposed to neuter harmful biases by exiting the position if a specified profit or loss is reached, Mr Imas found that few investors reached their take-gain orders, having already sold manually rather than risk their profits disappearing. Meanwhile, they tended to cancel and blow through their stop-losses, preferring to keep gambling rather than take a certain hit.难怪散户对此并不擅长。芝加哥大学的亚历克斯·伊马斯（Alex Imas）研究了那些在进场交易时设置止盈和止损指令的投资者行为。虽然投资者本应在达到指定的盈利或亏损点时退出头寸，从而消除有害的偏见。但伊马斯发现，虽然投资者设置了止盈线，但实际操作中很少会真的触发，因为在上涨阶段他们早已手动卖出，不愿拿已经获得的收益冒险。价格下跌时，他们又往往会取消止损指令并继续持有，宁愿继续赌博也不愿意承担损失。Are the pros any better? Only up to a point. Last year Mr Imas and colleagues published a paper on the buying and selling choices of 783 institutional portfolios with an average value of $573m. Their managers were good at buying: the average purchase, a year later, had beaten the broader market by 1.2 percentage points. But they would have been better off throwing darts at the wall to select which positions to exit. After a year, sales led to an average of 0.8 percentage points of forgone profit compared with a counterfactual in which the fund selected a random asset to sell instead.专业人士是否表现更佳？只能说稍好一点。去年，伊马斯及其同事发表了一篇关于783个机构投资组合买卖选择的论文，这些组合的平均价值为5.73亿美元。他们擅长买入：一年后，平均买入比大盘高出1.2个百分点。但在卖出方面，他们的表现还不如用扔飞镖的方法决定卖出哪个头寸。相比于随机选择资产卖出，一年后，他们的卖出决策导致平均错失了0.8个百分点的利润。注释：
1.Dart: n. a light spear
Source: https://www.merriam-webster.com/dictionary/darts
Unlike retail traders, the pros were not clinging on to losers. Yet neither were they making selling decisions analogously to how they make buying ones: by choosing the asset adding the least to their risk-adjusted return and offloading it. Instead they used a simpler heuristic, disproportionately selecting positions where relative performance had been very bad or good, and exiting those. As a result, they were throwing away two-thirds of the excess returns their skilful buying had won them.与散户交易者不同，专业人士并不会执着于持有亏损的资产。然而，他们在做卖出决策时并不像买入决策那样，选择对其风险调整后收益贡献最小的资产，将其从组合中剔除。相反，他们使用了一种更简单的启发式方法，更多地选择相对表现非常差或非常好的头寸退出。结果，他们抛掉了通过精明买入所获得的三分之二的超额收益。注释：
1.Cling: verb. to hold or hold on tightly or tenaciously
Source: https://www.merriam-webster.com/dictionary/cling
2.Heuristic adj. involving or serving as an aid to learning, discovery, or problem-solving by experimental and especially trial-and-error methods
Source: https://www.merriam-webster.com/dictionary/heuristic
3.Position trading: 头寸交易是一种常见的交易策略，交易者长期持有某一证券，持续持仓数月或数年。头寸交易者不关注价格的短期走势，倾向于从长期趋势中精确定位并获利。这是最接近投资的一种交易方式，区别在于购买并持有的投资者只能做多市场。
Source: https://capital.com/zh/position-trading
Ms Duke’s prescriptions for these problems are at once obvious and underused. Most important, recognise that buying and selling are two sides of the same coin and start treating them as such. Many investors keep watch lists of assets they may buy; they should also track those they have sold to test their decision-making. Fund managers routinely justify purchases to an investment committee in advance; they should have to do the same for exits. Traders of all stripes must set strict “kill criteria”, such as stop-losses, and actually stick to them (though even Ms Duke admits to having outstayed hers at the poker table).杜克女士对这些问题的解决思路非常直白，却未被广泛采用。最重要的是，认识到买入和卖出是同一枚硬币的两面，并以这样的方式对待它们。许多投资者会列出可能买入资产的观察名单；他们也应跟踪自己已卖出的资产，以检验其决策。基金经理通常会在购买前向投资委员会说明理由；卖出时也应如此。各种类型的交易者必须设定严格的‘止损标准’并严格遵守（尽管杜克女士也承认她自己在牌桌上有时也会该放手时未放手）。Professionals face constraints that prevent them from selling perfectly. Timing may not be in their gift: the capital could be needed for another purchase, or to return to investors. But if the faces in Oslo were anything to go by, many will now be giving their exit strategies a good deal more thought.专业人士面临着一些限制，使他们无法完美地卖出。卖出时机可能并不由他们掌握：资金可能需要用于另一项购买，或返还给投资者。但倘若从奥斯陆会议上的与会者反响来看，许多人现在将会更加认真地思考他们的退出策略。翻译组：
Martina，想做REST的I人
Humi，学习财经的金融小白，不负韶华，平视世界
风筝，想退休
Harold，不狂不放不申花
Cecilia:，今年过得贵妇一点
Intro，政府临时工，前理想主义者兼积极的悲观主义者
会买的是徒弟，会卖的是师傅，会空仓的才是祖师爷。
文科生在高中就会学到一个比较简单使用的模型就是价格围绕价值上下波动。然而为什么价格会上下波动。
首先，经济学原理告诉我们供求关系决定价格，供求变动引起价格变动。再一个就是各种经济因素、政策、外部事件等因素构成的对预期的影响。基于这两大原因，价格就成为了一个时期相对的指标，即所谓绝对的高价也没有所谓绝对的低价。例如，一个行业政策可以让一个企业的核心业务的价值直接归零，对，就是教培行业。对于这种极端行业政策下的反应，斩仓出清是所有投资人本能的反应，只要没有买盘，价格就可以不断的下跌，直到跌到了现金价值。这时候所谓的会卖的是师傅，体现出的是老师傅极强的交易纪律和出色的风控能力，把风险降到最小，损失降到最低。当然跟某些做时间的朋友的大佬不能比，他们就跟次贷危机时的高盛一样，总是能先别人一步，那就不是师傅和徒弟的事了。
在大A，在上涨面前更能体现会卖的是师傅，无论什么利好，无论什么预期，就算十几年的成长预期，2个月都能给直接涨到位。看不懂的就做过山车，享受一下财富的泡沫，看得懂的自然就会在崩盘前拂袖离场。
一鲸落万物生，远离修罗场，经历过了周期变动，起起落落，知道能力的边界，知得失，懂进退，是得天道者，这就是祖师爷。祖师爷为什么牛逼，因为上涨的因素千千万，祖师爷只做自己看得懂的事情，例如祖师爷是研究宏观的，那祖师爷只会在宏观驱动的时候来加仓，除此之外都是空仓等待，例如祖师爷是看产业的，那祖师爷只会在产能出清结束的前期来加仓，其他时候都是看云卷云舒。
一切都是认知变现，只做看得懂的，你也可以是祖师爷。
