Which country has the largest stock of brilliant people? The answer to this question depends in part on raw brainpower, but also on the size of a country. Exclusively for Business Insider, Dr. Jonathan Wai, a Duke University Talent Identification Program research scientist and psychologist, compiled a new ranking of countries based on scores on the 2009 PISA assessment, which tests reading, math, and science competency in 15-year-olds. Multiple researchers have found that these tests, administered by the Organization for Economic Cooperation and Development (OECD), are a good measure of "g," or general intelligence. In our list, the rank order...