The discovery of match fixing in Japan’s national sport, sumo wrestling, is a good illustration of why using N=all need not mean big. Thrown matches have been a constant accusation bedeviling the sport of emperors, and always rigorously denied. Steven Levitt, an economist at the University of Chicago, looked for corruption in the records of more than a decade of past matches—all of them. In a delightful research paper published in the American Economic Review and reprised in the book
Freakonomics, he and a colleague described the usefulness of examining so much data.