以扔硬币为例。13亿中国人中找到扔20次硬币全朝上的人不会太难,应该有1300人左右,如果其中的150人都来自海南省某个地方,比方说张家村,这个事实是不是如有朋友说的‘很震撼’ 呢?
调研下去,我们发现:这150个人都姓张,回溯源头,都出自一个共同的祖先,张氏宗主。张氏宗主非常智慧,早就预见到几千年后这个扔硬币比赛,因此,祖传有扔硬币秘芨,教授扔20次硬币全朝上的原则和方法,传给所有的张氏后人,而且不得外传。另外,这150个人虽然个性有不同,年龄有大小,但他们基本上都是遵循祖传秘方里的原则和方法来参加扔硬币大赛的。
这时,你是不是觉得,太TMD的震撼了!谜底揭开了,圣杯找到啦。这些人可以被称为‘张家村的超级扔币者’ ?
且慢,进一步调查发现,中国人中姓张的有1。5亿多,这些人也都熟读张氏宗主的秘芨,参加扔硬币大赛时,也基本上遵循祖传秘方,但很遗憾,这1。5亿多人中扔20次硬币全朝上的除了张家村那150人外,非常非常少,比方说只有30个。所以,总共只有180人。
这样问题就来了:虽然1。5亿人中出180个扔20次硬币全朝上的人比平均概率要大一点,但你还敢那么自信,还能得出这样的结论:张氏扔硬币秘芨就是圣杯,就是比别的方法好吗?一百万人里出一个扔20次硬币都朝上的人与八十万里出一个有很多区别吗?如果前者符合随机理论,后者不也基本符合吗?
这时再回头找为什么150人集中在海南省‘张家村’ 的原因,就可能会发现以前没有想到的因素。比方说,很可能是因为海南省张家村风景优美,由于房地产热在中国方兴未艾,张家村的房价被炒翻天,因此,只有富豪才能买得起这里的房子,住在海南省张家村本身就是一种身份的标志。而且,由于开发商姓张,规定不卖给外族,因此,海南省张家村实际上是中国张氏富豪的集结地。至于会扔硬币的人与富豪的正关联性那么大就是另外的,不需要在这里讨论的问题了,反正,张氏秘芨没有原来传说的那么神乎其神。那种认为,因为150位扔硬币成功的人都出自海南省张家村的事实足以说明张氏秘芨比别的方法好,扔20次硬币都朝上的机率不再是随机的论证方法是不充分的,也是站不住脚的。
当然,上面只是一个比方,但我想已经足以说清楚这一点:在没对价值投资者总体进行审视前,仅凭几个个例,是没法达到巴非特想驳倒有效市场理论的目的的,更谈不上证明了价值投资法理论高人一筹这一点。
也许,找为什么巴非特周围都是价值投资成功人士的原因是非常容易的:物以类聚,人以群分。象巴非特这种1969年就有2500万身价的巨富,如果接触的都是穷人,才让人感到奇怪呢。因此,巴非特周围形成一个价值投资成功者的小圈子不但不奇怪,还是十分自然的。不是吗?
说到这儿,我们基本可以拨开第一个迷雾了:
‘价值投资法适合于大多数人,如果不是所有的人的话。’是价值投资信徒们竭力明示或暗示的意思,但没有证据支持这一点,巴非特的论证方法也是经不起推敲的。
如果想严格而科学的证明,大多数价值投资者也是失败者或者说被市场击败者(underachievers),可能需要一个大规模的,长时期(可能得持续十年二十年) 的跟踪调查,非一般人的人力和物力所能承担。我们能做的大概是,看看参与美国股市的以价值为导向的共同基金的多年的表现,至今为止,我们还没听说过,多数以价值为导向的共同基金的表现能够超越市场,不然,也就不劳巴非特发表那篇所谓的‘经典演说’来煽风点火了,直接出个所有的,有一定历史的(包括那些消失的),以价值为导向的共同基金表现的统计数据岂不是更简单明了,也更有说服力?
如果说第一个迷雾的说法很多时候价值投资者还只是暗示的话,那么下面这个迷雾,价值投资者们就是在赤裸裸的误导别人了。
‘投资和价值投资法非常简单。’
(‘投资和价值投资法非常简单。’)
表达这种意思的说法经常出自价值投资者之口,举个例子,在一篇巴非特访谈里,巴非特就这么回答别人的问题:‘。。。15你为什么不进行其它投资? 既然股市这么简单,这什么还要买房地产呢?根据价值进行投资是如此地简单易懂,以至于到大学拿一个经济学博士显得是一种浪费。。。。
巴非特作为一个成功的投资者,不管他是拽还是其他什么原因,如果在私下里,圈子里这么说说倒也无妨。但是,当他面对媒体,当他知道很多人将他的话非常当回事时,他这么说就有了误导的嫌疑。
价值投资真的是‘如此地简单易懂’ ,股市真的是‘那么简单’ 吗?好象并不是这么回事。
价值投资法的两大基石,内在价值和安全边际,看上去十分简单,但里面的内容却是一直在变的,而且有的变化还很大。内在价值估算法在几十年实践中就发生了本质的变化,从账面价值变化到未来现金流量折现法,‘内在价值’ 的名称没有变化,但由于着眼点从估算已知存在的资产演变到预测估算将来的财务状况和指标,这是质的变化,有朋友表示异议,我想还是让价值投资的鼻祖的言论来说话吧。
These conditions do obtain with regard to some growth stocks, as they are identified by analysts; and highly satisfactory profits are made from that work. But the results vary a great deal with the skill of the selector, and perhaps with ‘the luck of the draw.’ It is quite questionable to my mind whether you can establish a technique of a communicable sort --- that a good instructor can pass on to his pupil --- by which you will be enabled to identify those stocks not only which have good prospects of growth but which have not already discounted pretty much those prospects in the market.
如果你觉得这一段话不够,我再引几段出自同一个地方的话(段与段之间是不连续的,但都在上面一段的前面):
We have been trying to point out that this concept of an indefinitely favorable future is dangerous, even if it is true; because even if it is true you can easily overvalue the security, since you make it worth anything you want it to be worth. Beyond this, it is particularly dangerous too, because sometimes your ideas of the future turn out to be wrong. Then you have paid an awful lot for a future that isn’t there. Your position then is pretty bad.
The concept that investment value is dependent upon expected future earnings is undoubtedly a more persuasive and a more logical one than thinking of value in relation to past earnings only, or in relation to the par value printed on the certificate, or any other stage in between. But I must emphasize to you that this concept does not make the job of the security analyst easier. On the contrary, it makes it a great deal harder, and it places him in a serious dilemma, for now the past earnings, with which he can become very closely familiar and which he can study with a great deal of skill and ingenuity --- those past earnings unfortunately are not determinative of value. And the element which is determinative of value, the future earnings, is just the thing which he cannot analyze with any real feeling of assurance as to the correctness of his conclusions.
…the discrepancies in market movement are so great that they should add an extra note of caution in our attitudes toward our future calculations. For even if we knew what was going to happen to a company, in terms of its business and its earning power, we might not be able to make too good a prediction as to what was going to happen to it in the market price, which interests us a good deal. That is just an added reason for being either as cautious as possible in regard to our own decisions on security purchases, or else protecting ourselves as much as we can in our own thinking and in our statements by qualifying comments, whenever we begin to make predictions as to the future.
这个人就是本杰明格雷汉母,那几段话节选自他1946至1947年间在纽约金融学院(New York Institute of Finance) 发表的多次演讲,题目是‘证券分析中的现实问题’(Current Problems in Security Analysis) 。