From: John Conover <firstname.lastname@example.org>
Subject: Chances of NASDAQ being down this far?
Date: 30 Nov 2000 08:22:14 -0000
The NASDAQ's down, roughly, about 50% since mid March, (5132.50 at its maximum, to 2642.49 today.) There have been about 170 trading days since then, and the deviation, (square root of the variance = root mean square,) of the fluctuations is about 2% per day, (meaning that for 68.3% of the time, the day-to-day fluctuations were less than 2%.) The average magnitude of bull and bear markets follows a square root function in time, (Black-Scholes dogma, where deviation = risk,) so a standard deviation at the end of 170 trading days would be 0.02 * sqrt (170) = 26.1%, (meaning that for 68.3% of the time, the change in the index would be less than +/- 26% at the end of 170 trading days.) Or, the current bear market is about a two sigma, (50% / 26%,) affair-meaning that what we are seeing has about a 0.0228 = 2% probability. In other words, we would expect to see the market down, at least as much as its down now, (in a year,) in only 2 years in a century. John BTW, it works out about right. The only time a major US equity indice has lost 50% of its value in a year, in the last hundred years, is 1929/1930 and 2000. -- John Conover, email@example.com, http://www.johncon.com/