New Top Regulator of Exchanges Named

Erik R. Sirri, an economist who specializes in the structure of securities markets, has been named the new director of market regulation at the Securities and Exchange Commission, the agency announced Monday.

The appointment by SEC Chairman Christopher Cox fills a high-level position at the agency, leading the division overseeing the nation’s stock exchanges, which has been without a permanent director for months.

Sirri, 48, was the SEC’s chief economist from 1996 to 1999. He is a finance professor at Babson College in Wellesley, Mass., and currently a visiting scholar at Harvard Law School.

Sirri also has been a member of the economic advisory board of the Nasdaq Stock Market and the board of the Boston Options Exchange, and was a governor of the Boston Stock Exchange.

Before his career in finance and economics, he worked on planetary astronomy missions for NASA and on space surveillance sensors in the aerospace industry.

He will begin his new job Sept. 12.

Sirri has a bachelor’s degree in astronomy from Caltech, an MBA from UC Irvine and a doctorate in finance from UCLA.

Last month, Cox named Conrad Hewitt, an accountant with experience in corporations, state government and a Big Four accounting firm, the agency’s chief accountant.