"Rudisha is my role model, " said 18-year-old Nijel Amos of Botswana, who took silver.

WSJ: Menu

My model looks for firms with 10-year average ROEs of at least 15%, and 10-year ROTCs of at least 12%.

FORBES: How To Beat Inflation? Build A Buffett-Inspired Moat

It has made negative economic earnings (meaning its return on invested capital has been lower than its weighted average cost of capital) every year going back to 1998 when my model begins.

FORBES: Financial Sector Funds And ETFs Need Less Citi, More Discover

My Buffett-based model also likes CNOOC, whose EPS have declined in just one year of the past decade.

FORBES: Apple, SAP And Three Other Large-Cap Growth Stocks To Buy Now

Global Payments has upped EPS in every year of the past decade, the sort of dependable, predictable results my Buffett-based model likes to see.

FORBES: Three Financials Buffett And Combs Would Buy