Professor Dahl and the paper’s other author, Stefano DellaVigna, an economist at the University of California, Berkeley, attach precise numbers to their argument: Over the last decade, they say, the showing of violent films in the United States has decreased assaults by an average of about 1,000 a weekend, or 52,000 a year.

Crime is not merely delayed until after the credits run, they say. On the Monday and Tuesday after packed weekend showings of violent films, no spike in violent crime emerges to compensate for the peaceful hours at the movies. Even a few weeks later, there is no evidence of a compensating resurgence, they say.

The findings in their paper are part of a recent wave of economic research in what might be called the “freakonomics era.” Practitioners of the dismal science are transcending traditional subjects like labor and markets, and are now crunching numbers to evaluate matters like cheating among sumo wrestlers or the effects of a crackdown on cocaine.

In this case, the authors have waded into a long-simmering debate about media violence, with their findings likely to attract controversy: Their conclusion seems to collide with the research of psychologists, which has fed concerns by parents and policy makers that brutal imagery in films, video games and other media sows aggression in American life by rendering viewers insensitive to horrific acts.

“There are hundreds of studies done by numerous research groups around the world that show that media violence exposure increases aggressive behavior,” said Craig A. Anderson, a psychologist and director of the Center for the Study of Violence at Iowa State University. “People learn from every experience in life, and that learning occurs at a very basic level of brain function.”