The past six months have been a hard time for some high-profile hedge funds. Crispin Odey’s Swan Fund and Bill Ackman’s Pershing Square have made losses of sufficient magnitude to wipe out years of accrued profits. Other star funds, from Blackstone’s Senfina to Paulson & Co, have also seen the second quarter of this year turn into a bloodbath.

一些知名对冲基金在过去6个月处境艰难。克里斯平•奥迪(Crispin Odey)的天鹅基金(Swan Fund)和比尔•阿克曼(Bill Ackman)的Pershing Square出现大幅亏损，抹掉了多年来累积的利润。从黑石(Blackstone)的Senfina到Paulson & Co，其他明星基金也在今年第二季度遭遇巨额亏损。

Some of the losses are attributable to the normal things that go wrong in investing — mergers which fall apart, commodity prices following their own logic and so on. But some of the worst pain has been caused by trades which looked like they made a lot of sense at the time. Pershing Square’s losses, for example, are largely attributable to one stock — Valeant and one macro theme: short China.

一些亏损可归因于正常的投资失误——并购告吹、大宗商品价格走势遵从其自身规律等等。但一些最糟糕的损失是当时看起来非常明智的交易导致的。例如，Pershing Square的亏损在很大程度上归因于一只股票Valeant和一个宏观主题：做空中国。

Neither of these trades could be considered a dumb mistake. Valeant had been one of the best-performing stocks in the pharmaceuticals sector until last year. And speculating on a Chinese economic slowdown not only had a sound economic rationale, it was delivering the goods until quite recently. It all serves as a grim reminder that it is not always the bad ideas that do the damage. What you have to look out for is good ideas that have stopped working.

这两个交易当初都不算是愚蠢的错误。直至去年以前，Valeant还是制药行业中表现最好的股票之一。猜测中国经济放缓不仅有靠谱的经济理由，而且直到不久以前还颇有斩获。结果我们付出惨痛代价才明白，并不总是坏主意才会造成破坏。你不得不当心那些不再奏效的好主意。

At a brokerage firm I once worked for, a constant source of irritation for the research department was the Best Ideas portfolio. This was a model portfolio consisting of the analysts’ highest conviction “buy” recommendations with the greatest upside, hedged against a selection of the “sell” recommendations with the biggest downside. Its performance was, generally, terrible.

在我曾经工作过的一家经纪公司，研究部门常常感到不满的根源是“最佳想法”投资组合。这种组合包含分析师以最高信念给予“买入”评级，并坚信具有最大上涨潜力的股票，相对冲的是一些“卖出”评级，被认为具有最大下跌空间的股票。这种组合的表现通常非常糟糕。

However, the same firm also maintained a Head of Research’s portfolio. This was a similar long/short selection and its performance was much better. In fact, during the time I worked there, the Head of Research portfolio outperformed major market indices in bull and bear markets.

然而，这家公司同时还保持了“研究主管”投资组合。这是一个类似的多空组合，但其表现要好得多。实际上，在我在这家公司工作期间，研究主管的投资组合在牛、熊市期间的表现都跑赢了主要股指。

What was particularly impressive was that the head of research did no work at all in selecting his eponymous portfolio. It was simply constructed by taking the Best Ideas portfolio, and using a “stop loss” rule which took out any stock that had gone the wrong way by 10 per cent since being included.

尤其令人印象深刻的是，研究主管根本没有为这个以他的职位命名的组合挑选股票。它只是采用“最佳想法”组合，然后使用“止损”规则来剔除自纳入组合以来反向波动10%的股票。

It seemed to be the case that the Best Ideas portfolio had a lot of potential value in it but that all the positive returns generated by the good ideas, and more besides, was being destroyed by a comparatively small number of ideas that did not work, but which the analyst liked too much to downgrade.

“最佳想法”组合似乎有许多潜在价值，但好想法产生的所有正回报，被相对数量不多的未奏效想法破坏——但相关分析师过于喜欢自己的想法而不愿调降评级。

This seems to be a large part of the problem with the hedge funds this year. Mr Odey and Mr Ackman are strong-willed characters and both had a record which justified their self confidence. But all this goes to show is that it is not just mediocre investors who make mistakes.

这似乎是上述对冲基金今年面临的主要问题。奥迪和阿克曼都是意志坚强的人物，而且都有证明他们的自信正确的过往记录。但这一切表明的是，不仅仅是平庸投资者才会犯错误。

An old City saying has it that the definition of a “long-term investment” is a short-term investment that went wrong. The behavioural tendency it describes is one of the most dangerous things in finance. Of all the factors which drive someone to take unacceptable risks, the most common and most serious is arguably the refusal to admit that a mistake has been made.

伦敦金融城的一句老话是，“长期投资”的定义是出了错的短期投资。它所描述的行为倾向是金融领域最为危险的事情之一。在推动某人甘冒不可接受的风险的所有因素中，最常见且最严重的可以说是拒绝承认犯错。

This is not to say that the market is never wrong or that it is a good idea to be shaken out of a position by market volatility. Mr Ackman and Mr Odey have made their reputations and fortunes out of betting against the herd.

这不是说市场永远不会犯错，或者说被市场波动踢出某一头寸是个好主意。阿克曼和奥迪都曾因逆向押注赢得了名声和财富。

But it is always worth looking out for the indicators that a fund manager might be in denial. Changing rationales for a trade, ignoring bad news, blaming central bankers — these are all signs that contrarianism might have slipped into cognitive dissonance. Investors should remember that although Best Ideas portfolios are occasionally referred to as High Conviction, the two terms are definitely not synonymous.

但始终有必要留意基金经理死不认错的迹象。改变某一笔交易的理由、忽视坏消息，指责央行行长——这些都是逆向思维沦为认知失调的迹象。投资者应该记住，尽管“最佳想法”投资组合有时被称为“高信念”(High Conviction)组合，但这两个词绝不是同义词。