Who Saw It Coming?

“Your money is at risk… Anyone who would tell you otherwise is either a fool or a huckster. Then there are those who do warn of risk but package it into a simple numerical measure that seems to put it within manageable bounds. They're even more dangerous.

“Your mutual fund's annual report, for example, may contain a measure of risk (usually something called beta). It would indeed be useful to know just how risky your fund is, but this number won't tell you. Nor will any of the other quantities spewed out by the pseudoscience of finance: standard deviation, the Sharpe ratio, variance, correlation, alpha, value at risk, even the Black-Scholes option-pricing model.

“The problem with all these measures is that they are built upon the statistical device known as the bell curve. This means they disregard big market moves: They focus on the grass and miss out on the (gigantic) trees. Rare and unpredictably large deviations like the collapse of Enron's stock price in 2001 or the spectacular rise of Cisco's in the 1990s have a dramatic impact on long-term returns – but ‘risk’ and ‘variance’ disregard them.

“The professors who live by the bell curve adopted it for mathematical convenience, not realism. It asserts that when you measure the world, the numbers that result hover around the mediocre; big departures from the mean are so rare that their effect is negligible. This focus on averages works well with everyday physical variables such as height and weight, but not when it comes to finance…

“Today Google grabs much Internet traffic, and Microsoft represents the bulk of PC software sales. Out of a million submitted manuscripts, a handful account for the bulk of book sales. One percent of the U.S. population earns close to 90 times what the bottom 20% does, and half the capitalization of the stock market (close to 10,000 companies) is in fewer than 100 corporations…

“The economic world is driven primarily by random jumps. Yet the common tools of finance were designed for random walks in which the market always moves in baby steps. Despite increasing empirical evidence that concentration and jumps better characterize market reality, the reliance on the random walk, the bell-shaped curve, and their spawn of alphas and betas is accelerating, widening a tragic gap between reality and the standard tools of financial measurement.”

(“How the Finance Gurus Get Risk All Wrong.” Benoit Mandelbrot, Nassim Nicholas Taleb. Fortune: July 11, 2005. Vol. 152, Iss. 1; pg. 99)

LULLED BY THE CONVENTIONAL, dulled by the narcotic of normal science, trapped in the norm, we should have seen this meltdown coming. Blinded in the fluorescent light of hopeful greed, it is so easy to be seduced by the dominant illogic of analysis without thought. (See Andy Grove below... )

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