Wharton grad took job in arbitrage at Goldman Sachs 1982; worked with billionaires Edward Lampert, Thomas Steyer, Richard Perry. Left to launch Och-Ziff hedge fund with $100 million initial investment from Ziff brothers. Public offering last November; stock down 50% since. Assets under management: $33 billion. Flagship fund up 16% annually net of fees since 1994; rose 11.5% in 2007.