Carnegie Mellon University finance professor Chester Spatt will take a two-year leave from the school to become chief economist at the Securities and Exchange Commission.

Spatt, 50, will oversee the SEC's Office of Economic Analysis in Washington, D.C., and advise policymakers on the effect of economic regulation on the markets.

His appointment is effective July 1.

SEC Chairman William H. Donaldson said Spatt would offer insight and analysis during a "critical time for our financial markets."

Spatt, who received his doctorate in economics from the University of Pennsylvania in 1979, has written extensively on market structure, pricing and valuation and the impact of information in the marketplace.

In the 1990s, he argued against implementation of Pennsylvania's corporate anti-takeover law and advocated simplifying federal income tax laws with a flat tax.

Spatt said he was looking forward to working on important issues facing America's financial markets.

He will succeed Lawrence E. Harris, who is returning to research and teaching at the University of Southern California Marshall School of Business.