Robert Engle, of the United States, and Clive Granger, of Britain, have won the 2003 Nobel Memorial Prize in Economic Sciences for devising statistical methods that improve the analysis of economic phenomena.
It was the fourth straight year in which the economics prize was dominated by academics working at U.S. universities.
Mr. Engle is on the faculty at New York University, and, although he is a British subject, Mr. Granger teaches at the University of California at San Diego.
Both men were lauded for helping to improve analysis of such economic indicators as economic growth, prices and interest rates.
Mr. Engle was cited for his development of a new statistical model to measure volatility on financial markets over time. The Royal Swedish Academy of Sciences says Mr. Engle's models have become indispensable tools for researchers and financial analysts, who use them in asset pricing and in evaluating portfolio risk.
Mr. Granger's research was directed at another aspect of economic movements over time, so-called non-stationary data, such as a long-lasting effect from a temporary disturbance in economic growth patterns. The academy says Mr. Granger discovered that statistical methods used to measure stationary data, which do not grow over time, could yield misleading results when applied to non-stationary data.
The announcement of the economics prize winners came hours after the Swedish Academy awarded the 2003 Nobel Prize in chemistry to two Americans, Peter Agre and Roderick MacKinnon for their research into cell membranes.
This year's Nobel Prize season got under way last week, when the literature prize went to South African writer J.M. Coetzee.
On Monday, American Paul Lauterbur and Briton Peter Mansfield were awarded the Nobel Prize for medicine. And on Tuesday, Russo-American Alexei Abrikosov, Russian Vitaly Ginzburg and British-American Anthony Leggett won the Physics Prize.
The most prestigious of the Nobel awards, the peace prize, is to be announced on Friday in Norway.