And it has also put the world into a financial condition where we need to fix the Math, for the Economy to get well. At this point; there need to be repairs to both the mathematical models used in the Finance sector and to the way those models are applied. And what people don't seem to grasp is that there can be no transparency, in the Finance sector, until some of those repairs are made. Even the best model will fail to represent reality, if we fudge the data overmuch - to show the desired result. Now economists are beginning to re-examine past market data to include a broader time segment, as well as using the full extent of variations as a guideline, in order to properly include catastrophic events in their assessment of what is normal or characteristic. In the past, it was considered sufficient to use a segment of time and range of variations when the market was well-behaved, to determine its normal behavior. This approach treats all rangy or catastrophic events as impossible, rather than merely unlikely, promoting a kind of false determinism that allows lies to appear factual.

So; if we want to have real accountability, we need to fix the Math to an extent where it more accurately reflects reality. Mathematician Benoit Mandelbrot correctly pointed out several flaws in financial Math in common use, and predicted there would be problems down the road if the errors were not fixed, but he was looked at as a "Chicken Little' telling people "the sky is falling" rather than an honest mathematician, trying to save people some grief. People were all too eager to believe another mathematician, David X. Li, when he devised something called the Gaussian Copula Function, which became the basis for credit-swap derivatives trading. Li cleverly knitted together two risk-estimation formulas, one used in engineering for equipment failures, and the other from actuary for attrition rates due to disease or death. He included plenty of caveats in his paper, about the need to use all the data, but also made a convincing case for the illusory notion that precisely estimating risk allows us to reduce it, and thereby create financial instruments with zero risk.

Of course; the claim of zero risk seems rather absurd after the fact of a market crash fueled in large measure by trading in such instruments. But at the time Li's paper came out, it was hailed as a major advance in financial Math, and there was even talk of a Nobel Prize for his contribution to Economics. Well; it turns out Mandelbrot was nearer correct, but we now have trading in financial instruments (credit-swap derivatives) whose founding premise was discovered to be faulty. Yes; there must be greater transparency and some form of regulation of CDOs is necessary, in order to assure fairness. But I wonder if the economists and quants have really addressed some of the basic problems caused by bad Math, which allow for greedy and devious people to play both sides without it being apparent. It is as though the numbers, and the Mathematics itself, were used as a shield or weapon instead of an instrument of the truth. Math is used in finance because of its capacity to represent complex transactions accurately and transparently. But one has to use the right Math for the job, and though Mathematics as a whole has continued to evolve, much of the Math used in Finance is outdated.

2010 Jonathan J. Dickau - reproduction for non-commercial purposes is allowed

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