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Waiting in line isn't what it used to be. A robo-voice tells Red Line riders when a train is entering the station. Waist-high stanchions and nylon ropes force serpentine lines in fast-food places. E-Z Pass and cash toll-payers don't mix lanes. Soothing, eh?
You can thank Professor Richard Larson for that.
Larson, director of the Center for Engineering Systems Fundamentals and Mitsui Professor of Engineering Systems and Civil and Environmental Engineering at MIT, is a key figure in the field of queue psychology--the study of how to make waiting bearable and even enjoyable.
Back in 1976, Larson sat in a line he just couldn't forget.
At the time, he was pure operations research; his focus was on urban service systems. The line that got etched in his mind--a line that launched a whole new field--started out with a simple errand: to buy his young son his first bike.
"It looked so easy: My wife and kids would wait in the car while I went into Sears and got the bike. We'd be home by dinner," recalls Larson SB '65, SM '67, PhD '69.
All went well for a time. He picked out the bike, paid, took his receipt to a window at the back of the store and confidently assumed his place, second in line.
"The woman sitting in first place was weeping. She'd waited over an hour for a waffle iron, while others had gotten their items. I sympathized, sure it was a fluke. Then a half hour went by. Others got their things before I did. By the time I got back to the car, my kids were crying and I was furious," Larson says.
He returned the bike box, unopened, two days later, with a lifetime pledge to never, ever, darken the doors of that Sears again.
"I was prepared to be patient. I was happy to comfort the weeping woman. I believed I would get my bike when my turn came. But this was a HUGE violation of 'first-come, first-served,'" Larson says.
Larson couldn't get the experience out of his head.
"So I did what MIT teaches all engineers to do: Generalize! Look for a bigger picture. Look for patterns," Larson recalls.
The pattern he spotted went beyond aggravation into the area of social justice. After all, people who skipped ahead of him in line caused his place--his just and rightful place--to slip further from the bike pickup window. Skipping ahead and slipping had to be studied, too.
Larson sought and received funding from the National Science Foundation to research the psychology of queuing, including the slips and skips of queues gone bad. With that, his career took a surprising and fruitful new turn.
His seminal paper, "The Psychology of Queuing and Social Justice," was published in Operations Research in 1977, with journal articles, interviews and articles on his work following in The New York Times, and on radio and network television. To this day, he is asked to speak on queuing psychology.
Larson's research led to new computational techniques, such as the Queue Inference Engine and the Hypercube Queuing Model, and to whole new approaches to easing congestion in urban traffic, fast-food lines and banks.
Larson doesn't credit himself with the birth of queuing psychology, despite his success in defining the field. Applied queuing psychology itself was born in 1955, when Disneyland opened in Anaheim, Calif., he says.
"Who but Disney could get people to wait 45 minutes for a two-minute ride? Their visitors are so distracted, they voluntarily prolong their waits," Larson says.
Larson describes this as an A+ application of queuing psychology. But most of life happens outside of theme parks, and most people in queues grow cranky. Skipping can even provoke what he calls "queue rage."
For a queue to work well, people must believe their patience will pay off. They must believe in their queue's efficiency and fairness. They must have signs of hope--the train is coming; your call will be answered in 12 minutes.
Since Larson's first paper, the field has broadened in scholarly and social venues. Larson has supervised a half-dozen theses in this area, most recently in the psychology and physics of urban drivers' search for affordable on-street parking.
New queuing research has found parking hunts to be a major cause of urban traffic congestion, according to Larson.
Larson himself even got a new identity thanks to that fateful errand 30 years ago. For a time, he was known as "Dr. Q," dispenser of 10 annual tips on avoiding lines during holiday shopping.
A version of this article appeared in MIT Tech Talk on February 6, 2008 (download PDF).
