Monday, 22 June 2009

Learn from the Worst: Expert

With all the convoluted factors that drive the stock market, predicting which way it will go in the short term is just about impossible.

But wait. A certain group of people that the media refer to as "experts", how are their predictions? These self-assured sounding commentators that we find on TV, the Internet, or print news tell us that they know just what the latest round of earnings reports or economic figures will mean for stocks. After all, they're experts; don't they have to be at least pretty good at predicting economicand stock markt trends?

Unfortunately, research shows that they don't. Let's see how well the stock picks of most "experts" who appeared in the media actually did. Research on this showed there was no consistency or predictability in the performance of these pundits. The best performers in one week, one month, one quarter, six months, or one year were almost guaranteed to be entirely different in the next period; basically, you couldn't make money by picking a top performing expert as measured over a short period of time and following him or her.

"Experts" are far from infallible. A study found the best forecasters - even the "experts" - couldn't explain more than 20% of the toal variability in outcomes. "Consider what this means. On all sorts of questions you care about - Where will the Dow be in two years? Will the federal deficit balloon as baby-boomers retire? - your judgement is as good as the experts'. Not almost as good. Every bit as good." (This was from a 2006 article for Fortune, Geoffrey Colvin examined this concept by reviewing the book Expert Political Judgment: How Good Is It? How Can We Know?)

Colvin also noted that the study found that the experts' "awfulness" was pretty consistent regardless of their educational background, the duration of their experience, and whether or not they had access to classified materials. In fact, it found "but one consistent differentiator: fame. The more famous the experts, the worse they performed," Colvin said.

So, if that's the case, why do so-called "experts" still get so much publicity and air time? The reason is another result of our human nature. As humans, we want to believe the world " is not just a big game of dice and that things happen for good reasons and wise people can figure it all out." And since people like to hear from confident sounding experts who appear to be able to figure it all out, the media likes to give them air time - and the experts like to get that air time because it pays. This relationship was described as a "symbiotic triangle" - it is tempting to say "they need each other too much to terminate a relationship merely because it is based on an illusion."

The bottom line: Just because someone sits in front of a camera with a microphone and speaks confidently doesn't mean he or she has any sort of clairvoyant powers when it comes to the stock market. In fact, the odds are that four out of every five times, they'll be wrong!

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