Anyway, the reasons I start this new thread are not just because of recent exchange on chartist vs fundamentalist in the
書中自有黃金屋 thread, but also because I recently read a book "The Dhandho Investor" by Mohnish Pabrai.
This is a short book on value investing. The author is a huge fan of Warren Buffet. I got to know the book from an Ed Thorp article.
The first part of the book is stories of successful business ventures, especially the Asian Indians who now owns most of the motels in the US. The key lesson is buy value & limit downside & be contrarian. The second part shifted the focus to "rules" on how to invest in value. Just like any other books on success stories, the examples may be subject to survior bias, and I also suspect there are a fair amount of urban legends in the stories.
To me the more interesting part of the book is the author's attempt to articulate "value" in the form of expected value, i.e. sum of all scenarios (probability * payoff). In theory, any time the expected value is >100%, then it's a good investment to make.
In analyse a company's financials and business prospect, I think it's very difficult to accurately assign probabilities & payoffs to various outcomes. To compensate for this difficulty, the author seems to propose that one should only invest if the expected value is approaching 200% or more, thus widen the margin of safety.
Another important philosophy of the author is to concentrate the portfolio (vs diversification) by "Bet Big, Bet Few, Bet Infrequent". This idea contrast sharply to the quantitative investors "Bet Small. Bet Frequent" idea in the
Ed Thorp &
CRW threads. In the quantitative approach, the probabilities & payoffs can be and indeed are projected accurately and explicitly, thus even a small EV edge, e.g. 102%, can be exploited. If turnover is fast enough, even low margin can translate to high return on capital employed. But in conventional equity investment (the main focus of this book), perhaps the EV cannot be computed accurately, thus lead to the contrast in philosophy?!