Calling the data on such short-term swings suspect, he said the rebound was largely a result of PC makers preparing for Christmas sales.

For stock investors, such practices by professional managers can cause volatility, and seemingly inexplicable, short-term swings in share prices.

Such services, however, typically smooth over short-term swings in auction prices.

And stock prices are subject to much wider short-term swings than home values.

But criminologists say it is harder to predict, or understand, short-term swings in homicide rates, which may not be statistically significant.

But Mr. Utsumi's comments did not seem directed at short-term swings in the currency markets.

Yesterday's volatility was the most extreme example of a tendency for wide short-term swings that the stock market has exhibited all year.

Still, investing with an eye toward retirement can insulate bond investors from short-term swings in interest rates.

The markets that possess those in greatest abundance, he said, are overseas, and he expects that to remain the case despite short-term swings.

However, workers who do can find themselves extremely vulnerable to short-term swings in the market.