Many years ago I bought this book about the stock market. In retrospect, it is the worst book I've ever bought because it made me believe in efficient capital markets. The author made his point with a lot of arrogance - just like finance professors did 15-20 years ago. At the time the markets very certainly not as efficient as the author believed. There have been several updates to the book, but the condescending voice of the author remains.
For the statistically interested, the problem with a lot of old finance (and also not so old) research was that it was testing the theory that the market was efficient. That is poor philosophy of science. You should always test the opposite of what your theory stipulates. If you can reject the opposite, your theory is as supported as it can be (standard Popper). The finance profession in their ignorance of philosophy of science tested it the other way around. This means that they could too easily conclude that the markets were efficient. Not a word about such complications in this book. Why is this relevant? I would say that the author is less critical of research that supports his preconceived opinion (as stated in the first edition of the book).
I did not realise this bias when I first read the book. Instead, I believed the author's conclusion that the markets must be so efficient that it is fruitless to try to beat them. That was and is just plain silly. The markets are of course tending towards efficiency, so it is not easy to beat them. This is an important point. However, to state that they are efficient is just plain arrogant. So while there are some very good critical analyses in this book, ultimately it might make you believe in something that is very costly: That you cannot make more money in the stock market unless you are willing to take on a higher level of risk.
Currently a lot of academics are questioning the efficient markets. This research is not taken seriously by the author. I am reminded of Kuhn's comment that the new paradigm only becomes prominent when the old guard dies/retires. Furthermore, a lot of people with a PhD in finance start hedge funds to exploit anomalies in the market place instead of writing academic articles. Wouldn't this be worth serious consideration by the author? Still, there is still room for other inefficiencies. For instance the role of emotions is totally disregarded by academic-finance number-crunchers.
The author also has advice of how to invest. His view is to buy low-cost mutual funds. This is not awful advice, but still why would you buy mutual funds when the average fund doesn't even return average market returns? The only thing you know is that they take 1-3% in management fees every year. Do compound interest on that! In The Financial Times, the author recently argued that stocks in emerging markets are undervalued. It is hard to believe in efficient markets and write an investment column. So he just assumes (contrary to his book) that the markets are inefficient and have not priced those stocks correctly. Check out recent videos from 2011. He says that he believes in efficient markets when it comes to publicly available information. Then he proceeds to state that people in 1999 bought the wrong kind of stocks (Internet, technology), which were overvalued. Yes, I would agree those stocks were in a bubble. But honestly, then you cannot believe in efficient markets. These blaring inconsistencies are remarkable.
If you have read this far and want to give me negative feedback, be my guest. I posted a version of this review on an earlier edition of the book, and the review got trashed be believers. When you get a lot of negative feedback on a negative review on amazon that tells you the author has a lot of worshippers. That should make you worried.
A more rational response would be to read Justin Fox's The Myth of the Rational Market
. It tells a much more nuanced narrative about the efficiency of capital markets and prominent academics role in developing ideas and theories. The style of the book is not preachy at all. His stories show academic finance to be a very dogmatic environment in the 80s and 90s. You could be called a communist by the stars in the field and have your chances of employment reduced if you didn't sign up to the belief that markets are efficient. It is all described in Fox's book. Or read Shiller's Irrational Exuberance
describing how bubbles have been removed from finance textbooks and PhD syllabi because they doesn't fit with the rational actor model. He has the following to say about the efficient market hypothesis: "one of the most remarkable errors in the history of economic thought". Or read Montier's Behavioural Investing: A Practitioners Guide to Applying Behavioural Finance (The Wiley Finance Series)
(or his other books) for more evidence of imperfect markets. Or read Dreman's column in Forbes magazine.