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The Hawthorne effect takes its name from Western Electric’s Hawthorne Works in Cicero, Illinois, outside Chicago. From 1924 to 1927 researchers ran illumination experiments to see whether brighter lighting raised output. Productivity rose in the test room when the lights went up, but also in the control room where nothing changed, and it kept rising as the lights were dimmed, falling only near the level of moonlight. In 1927 Elton Mayo led the relay assembly experiments: two women chose four friends, and the six were moved to a separate room under a sympathetic supervisor, their output counted by relays dropping down a chute. Breaks, soup, sandwiches and a 4:30 finish all lifted output, and Mayo concluded the women worked harder because they felt special and functioned as a team.

The bank wiring room study of 1931 and 1932, run by Mayo and W. Lloyd Warner with 14 men, contradicted that hope. Piece-rate pay lowered output because the men feared management would cut rates or jobs, and their cliques enforced a slow pace with a punch on the arm called binging. The term Hawthorne effect was coined only in the 1950s by John R. P. French and Henry Landsberger. In 2011 Steven Levitt and John List found the original lighting data on microfilm at the University of Wisconsin in Milwaukee and saw only slight evidence of the effect. Richard Nisbett called it a glorified anecdote, J. G. Adair proposed a demand effect, and H. M. Parsons noted the women could hear the relays clicking down the chute.

• Six five-minute breaks a day lowered output by breaking the workers’ rhythm.
• Harry Braverman read the bank wiring study as evidence of power dynamics and class antagonism.
• Parsons argued the audible chute gave real-time feedback, making the gains a learning effect.
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