Sunday, December 09, 2007

The Efficient Market Revisited

There has been a lot of debate since the 1950s whether markets are efficient or not. Btw, if you are asking what the heck is an Efficient Market, you can read this posts first.

Label: Modern Portfolio Theory

Ok Efficient Market. Essentially, some academics came out with this theory that nobody can earn a superior return than the market return (ie average investment return) over an extended period of time bcos markets are damn bloody efficient. ie if there is an inefficiency (or a discrepancy between price and value), eg a stock is worth $5 but is only trading at $3, people will simply keep buying the stock until it is fairly valued. So no matter how hard you try, you can only earn the average index/market return if you invest in stocks/bonds whatever, which is about 8%pa.

As with academics, they made it complicated. So they came up with three forms of Efficient Market which I have forgotten what they are. But the message is nobody can beat the market whether you use fundamental analysis, or technicals or whatever intelligent tools you can come up with. So even if you managed to spot one inefficiency, you are just lucky and you won't be able to do it over and over again. The academics dare you to prove them wrong man! They really do! And sadly I think they are winning. Not 100% but quite close.

Having said that, actually there is a flaw in the EMH, or Efficient Market Hypothesis. The flaw is that the markets are not efficient to begin with. It becomes efficient bcos the market participants are constantly taking out the inefficiencies. Imagine 1 million investors/speculators in the market and everyone just managed to spot 1 price/value discrepancy, then the market will be quite efficient already right?

So the markets become efficient bcos there are lots of participants taking out the inefficiencies all the time. The thing is that most participants can probably pick out 1 or 2 inefficiencies during a certain time frame but not a hell lot over long periods. Hence in general, markets are quite efficient to any one person.

But what if they are those who can consistently spot inefficiencies and earn the difference between price and value? Does that mean that the market is not efficient? In my opinion, the markets are still efficient it's just that this group of people have superior tools to enable them to pick out more inefficiencies than others. Of course for those still blur blur one, we are talking about value investors.

One reason why value investors can do this is bcos of their investment philosophy and investment horizon. Most pple nowadays go for instant reward, taking quick profits. They are not interested in owning businesses, waiting for its value to grow over time. They want profits NOW. Hence although a lot of people may know about value investing, they either

1) don't believe it works; they just don't believe in the owning business thingy
2) may not want to practise it bcos it takes too long to see the fruits
3) they think they are practicing value investing but they still buy and sell stocks like oranges or mobile phones or cars

So those Superinvestors for Graham and Doddsville patiently buy businesses while the world revolves around trading stocks like oranges or mobile phones or cars and Voila! They beat the major indices flat with their 30 yr track record of 25-40%pa. But sad to say, there are probably only a handful of these people and they don't really have a strong statistical argument against the Almightly Efficient Market.

Conclusion: The markets are not 100% efficient but they are efficient enough such that you don't get a free lunch if you don't work hard enough for it. Work hard = read books / annual reports, do a lot of macro, industry, company analysis etc.

1 comment:

  1. The short-term market is a voting machine, the long-term market is a weighing machine. Think about that.