目前为止很多投资人的阅读习惯还是集中于阅读类似于Security Analysis 或者Common Stock Uncommon Profit这类书籍，当然有些人可能偏好欧奈尔的套路。不过从收益来说我们很难看到能持续获得较高且稳定的相对收益投资人，王亚伟也许永远是个异数。

我这里提出另外一个阅读的来源也许相对于那些所谓经典书籍的阅读更为重要，一个可信的推论是经典文献所形成的投资策略都为人所掌握，获得超额收益的可能性越来越低。我这里强调另外一个途径：文献阅读是及其重要的，这里的假设是更新的手段还不为人所知或者广泛运用，这时获得超额收益的可能性更大。下面我来举个例子：

http://s16/middle/4174cd114ca5eb4416c5f&690

上图来自Chen, H., M. Z. Frank, et al. (2005). "What Actually Happened to the Inventories of American Companies Between 1981 and 2000?" Management Science 51(7): 1015-1031.

文章大意我直接引用摘要（读不懂英文也不用看这篇博客了）：
    This paper examines the inventories of publicly traded American manufacturing companies between 1981 and 2000. The median of inventory holding periods were reduced from 96 days to 81 days. The average rate of inventory reduction is about 2% per year. The greatest reduction was found for work-in-process inventory, which declined by about 6% per year. Finished-goods inventories did not decline. Firms with abnormally high inventories have abnormally poor long-term stock returns. Firms with slightly lower than average inventories have good stock returns, but firms with the lowest inventories have only ordinary returns.

很显然这是可以形成一个长期的对冲策略，从而获得明显的超额收益，这篇文章的结论在A股市场也是成立的，至少我的分析是如此，但我也知道应该还没有人使用这种方法来形成对冲的策略，至少国内没人采用这一策略。

目前国内谈经论道的多，潜心研究的少，连赚钱都是如此，甚至所谓的学院派都是假的，满嘴的名词，还不如一块来读文献吧。