Economist Jack Kyser was the go-to expert on the business of Southern California for reporters who knew he would give them the perfect sound bite on everything from immigration to Michael Jackson.

The economic face of Los Angeles County for decades, Kyser was found dead at his home in Downey, associates said Monday. He was 76.

"He was a giant of a man," said Hasan Ikhrata, executive director of the Southern California Association of Governments, where Kyser was an adviser. "He was the most knowledgeable economist in the state of California."

Ikhrata said his office called authorities when Kyser did not appear as expected at the office on Friday or Monday. It was not clear exactly when or how he died. Ikhrata said Kyser had reported no health problems.

A Downey police sergeant and a Los Angeles County coroner's lieutenant said they had no information on the death.

Kyser had roles both in shaping public policy and explaining it to the public.

"He was affectionately dubbed the 'guru,' the 'godfather' and the 'voice of the Los Angeles economy' for his great depth of knowledge, insight and uncommon ability to articulate complex economic concepts and issues in simple and understandable terms," Bill Allen, president of the Los Angeles County Economic Development Corp., said in a statement.

Kyser spent most of his career as chief economist for the LAEDC, which named its research center after him in 2007. He had just retired this summer.

He also had a practical role in influencing the county's economic direction.

"For over 30 years, Jack Kyser served as the chief economist for Los Angeles County, shaping economic policy and spurring development and job creation," Mayor Antonio Villaraigosa said in a statement.

Kyser was born in Huntington Park and grew up in Downey.

He earned bachelor's and master's degrees from the University of Southern California, and worked in Omaha, Neb., as a teacher of economics and a forecaster for Union Pacific Railroad, the only time his career did not focus on the Los Angeles area.

He also worked for Security Pacific National Bank, First Interstate Bank and the Los Angeles Area Chamber of Commerce.

Kyser was not married and had no children.