Steven D. Levitt Quote

To answer this question with some kind of scientific certainty, what you’d really like to do is conduct an experiment. Pretend you could randomly select a group of states and command each of them to release 10,000 prisoners. At the same time, you could randomly select a different group of states and have them lock up 10,000 people, misdemeanor offenders perhaps, who otherwise wouldn’t have gone to prison. Now sit back, wait a few years, and measure the crime rate in those two sets of states. Voilà! You’ve just run the kind of randomized, controlled experiment that lets you determine the relationship between variables. Unfortunately, the governors of those random states probably wouldn’t take too kindly to your experiment. Nor would the people you sent to prison in some states or the next-door neighbors of the prisoners you freed in others. So your chances of actually conducting this experiment are zero. That’s why researchers often rely on what is known as a natural experiment, a set of conditions that mimic the experiment you want to conduct but, for whatever reason, cannot. In this instance, what you want is a radical change in the prison population of various states for reasons that have nothing to do with the amount of crime in those states.

Steven D. Levitt

To answer this question with some kind of scientific certainty, what you’d really like to do is conduct an experiment. Pretend you could randomly select a group of states and command each of them to release 10,000 prisoners. At the same time, you could randomly select a different group of states and have them lock up 10,000 people, misdemeanor offenders perhaps, who otherwise wouldn’t have gone to prison. Now sit back, wait a few years, and measure the crime rate in those two sets of states. Voilà! You’ve just run the kind of randomized, controlled experiment that lets you determine the relationship between variables. Unfortunately, the governors of those random states probably wouldn’t take too kindly to your experiment. Nor would the people you sent to prison in some states or the next-door neighbors of the prisoners you freed in others. So your chances of actually conducting this experiment are zero. That’s why researchers often rely on what is known as a natural experiment, a set of conditions that mimic the experiment you want to conduct but, for whatever reason, cannot. In this instance, what you want is a radical change in the prison population of various states for reasons that have nothing to do with the amount of crime in those states.

Related Quotes

About Steven D. Levitt

Steven David Levitt (born May 29, 1967) is an American economist and co-author of the best-selling book Freakonomics and its sequels (along with Stephen J. Dubner). Levitt was the winner of the 2003 John Bates Clark Medal for his work in the field of crime, and is currently the William B. Ogden Distinguished Service Professor of Economics at the University of Chicago as well as the Faculty Director and Co-Founder of the Center for Radical Innovation for Social Change at the University of Chicago which incubates the Data Science for Everyone coalition. He was co-editor of the Journal of Political Economy published by the University of Chicago Press until December 2007. In 2009, Levitt co-founded TGG Group, a business and philanthropy consulting company. He was chosen as one of Time magazine's "100 People Who Shape Our World" in 2006. A 2011 survey of economics professors named Levitt their fourth favorite living economist under the age of 60, after Paul Krugman, Greg Mankiw and Daron Acemoglu.