Fair play key to waiting in line

CAMBRIDGE, Mass., Nov. 20 (UPI) -- Fair play -- or the idea of first come first served -- is at the heart of most successful queues, a U.S. expert on lines of waiting people said.

Violation of fair play can lead to "queue rage," said Massachusetts Institute of Technology Center for Engineering Systems Fundamentals Director Richard Larson, who has researched queuing psychology for more than two decades.

This is one reason most banks, airlines and fast-food restaurants have switched from several open lines that force customers to choose the line they think is moving fastest to a single serpentine line, which guarantees first come first served, Larson said.

An exception to the fair-play rule is the express checkout lane at the supermarket, Larson told CNN.

Customers buying a couple of items don't expect to get in the same line as people with shopping carts filled to the brim, he said.

The exception points to an example of another queuing psychology principle, that people's willingness to wait is usually proportional to the quantity of service they expect to receive, Larson said.

In addition, researchers have found that people who know ahead of time how long they will have to wait are less anxious than those who don't, he said.