Elinor Ostrom and Oliver E. Williamson, two American economists, were awarded the 2009 Nobel Prize in economics early Monday.

Both will split $1.4 million from the prize. The first half of the award went to Mrs. Ostrom, a professor at Indiana University, who became the first woman to win the award.

She analyzed economic governance, especially the commons. Her work demonstrated how common property can be successfully managed by user associations.

The other half was given to Mr. Williamson for his analysis of economic governance where he showed that it is better to regulate the wrong behavior such as abuse of power of large private corporations directly rather than through policies that limit the size of the corporations.

Mr. Williamson is a professor at the University of California, Berkeley.