Sortition in the Bulletin of the Institute of Mathematical Statistics

The Bulletin of the Institute of Mathematical Statistics has published a column of mine that deals with the historical and theoretical connections between democracy and statistical sampling:

Democracy and statistical sampling

For about 2,500 years, statistical sampling was closely linked with democracy. “Selection by lot is natural to democracy, as that by choice [i.e., elections] is to aristocracy,” asserted Aristotle in the 4th century BC, following his own first-hand experience at Athens and the conventional wisdom of his time. Montesquieu concurred in the first half of the 18th century. It was only in the last 200 years, as democracy displaced aristocracy as the legitimate organizing principle of politics, that sortition—the delegation of power by statistical sampling—had to be air-brushed out of history and political science. […]

As part of the attempt to dismiss sampling as a political device it is sometimes claimed today that its use in Athens was motivated by the superstition that randomization allowed the gods to make the selection. However, the historical record indicates that the main motivation behind the practice was the law of large numbers. It was expected that sortition would produce a group that would mirror the population in important respects. This was often stated as an expectation of resemblance between the population and the sample in terms of wealth and social status (i.e., that most members would be poor commoners) but it was taken for granted that these characteristics would be correlated with certain interests and beliefs.

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