David Weidner

Last night, in a prime time spectacle, LeBron James announced which NBA team he's joining: the Miami Heat. He was only a free agent for a few days, but the machinations to woo the best player in basketball have been underway for years. In particular, The New York Knicks have suffered two terrible seasons as they cleared out players to make salary-cap room for big name free agents this signing season. Stocks even moved based on rumors he was coming to New York. Cleveland has calculated the impact of this one player on the downtown economy and regional business. It's in the hundreds of millions of dollars.

Stock markets around the world seem to be going haywire in recent weeks. We find out how global stock markets work, and why they’re so interconnected. John Authers is the Investment Editor for the Financial Times; David Weidner is Senior Columnist for Marketwatch.

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