Cobra Effect · People and organisations
The Ringelmann effect
The bigger the group, the less effort each person puts in.
6 cards, read aloud in 2:32, with a test and sources.
France, the 1880s. An engineer asks his students to pull a rope.
Max Ringelmann studies farm labour. Horses, oxen, men. He wants to know how much work a man can do, and whether a team does more. One at a time, each student pulls as hard as he can. Ringelmann measures the force. Then he puts them on the rope together.
Two men pull less than twice one man.
Three pull less than three times. By eight men, each is pulling roughly half of what he pulled alone. Ringelmann published the figures in 1913. He thought it was mostly a matter of timing. Eight men cannot heave at exactly the same instant.
It was not just timing. It was effort.
In 1974 Alan Ingham’s team blindfolded people and told them others were pulling behind them. Nobody was. The others only pretended. Still, the people who believed they were in a group pulled less hard. The loss was in the mind before it was in the rope.
That is the Ringelmann effect. Psychologists call it social loafing.
In 1979 Bibb Latané, Kipling Williams and Stephen Harkins asked people to shout as loud as they could. Those who believed one other person was shouting with them gave 82% of their solo effort. With five others, 74%. When your share of the result cannot be seen, part of you stops trying. Not out of laziness. Out of arithmetic.
It is why the big meeting decided nothing.
Twelve people asked to review a document, and nobody reads it, because eleven others will. A group project where the grade is shared and the work is not. The larger the pool, the thinner each person’s stake in it. And the harder it is to tell who pulled.
Make each pull visible.
Give every task one name, not a team. Keep groups small enough that easing off would be noticed. Measure individual contributions where you can, and say so. When you catch yourself easing off because others are on the rope, notice it. They are doing the same.
Sources
- Ringelmann effect, Wikipedia. The rope experiments, the 1913 publication, Ingham’s 1974 pretend groups, and the distinction between losing effort and losing coordination.
- The Mythical Man-Month, Fred Brooks, 1975. Why adding people to a project does not add their full effort, told from inside a giant software project. Communication overhead is its main culprit, and it pairs well with Ringelmann’s rope.
- Social loafing, Wikipedia. The modern name, the shouting and clapping studies of 1979, and what reduces it: small groups, visible contributions, and tasks people care about.
Nearby ideas
- The bystander effect. The more people who see a problem, the less each one acts.
- Brooks’s law. Adding people to a late project makes it later.
- The tragedy of the commons. Why shared things get used up, and how communities stop it.
- Milgram’s obedience experiments. Ordinary people follow harmful orders when the setting pushes them.
- Pluralistic ignorance. Everyone can privately doubt a rule that nobody questions out loud.
- Gall’s law. Complex systems that work grow out of simple ones that worked.
- Cunningham’s law. The fastest way to get the right answer is to post a wrong one.
- Pournelle’s iron law of bureaucracy. In any organisation, those who serve the organisation end up in charge.