Why is it that American football uses eleven players, Canadian football twelve, and Gaelic fifteen? Why eleven in European soccer? Why does baseball field nine players, basketball five, volleyball six, water polo seven, and cricket eleven? Simple as these questions are, they are deceptively hard to answer. But whatever the historical reasons, the number of people on a team has significant impact on performance. Here's why.
The earliest known attempt to investigate the relation between team size and productivity dates back about a hundred years to the now famous experiments by French engineer, Maximilien Ringelmann. In a set of simple rope pulling experiments he discovered that, in what is now known as the Ringelmann Effect, people's efforts quickly diminish as team size increases. Eight people, he found, didn't even pull as hard as four individuals. He rationalized the decay in effort by suggesting it was difficult for team members to coordinate effort, and left it at that.
