Revisiting the Hawthorne Effect (01-13-10)

Economists Steven Levitt and John List have re-examined the data from the research that originally gave us the term “Hawthorne Effect” which is the “idea that the very act of being experimented upon changes subjects’ behaviour.”  During the original project at a manufacturing plant, lighting levels were changed (so that the workplace was either brighter or dimmer) but worker productivity did not vary in a reasonable way, “it did not matter what was done, so long as something was changed, productivity rose.”  The re-examination indicated that there were no systematic changes in productivity related to experimental actions.  As reported “It turns out that idiosyncrasies in the way the experiments were conducted may have led to the misleading interpretations of what happened.”  Light levels were always changed, for example, on days when the factories were closed, but workers at the test plant always seem to have been more productive on their first day back at work.  In addition, productivity fell when the experimentation stopped at the beginning of the summer, but output generally fell at that plant during the summer. 

“Questioning the Hawthorne Effect:  Light Work:  Being Watched May Not Affect Behaviour, After All.”  The Economist, vol. 391, no. 8634, p. 74.