The effect of simply being studied, usually improving performance no matter what changes are made to the circumstances. The effect is often attributed to being the subject of focused observation. It is named after the Hawthorne works of the Western Electric Company in Chicago where seven studies were carried out on the effects of changing working conditions (e.g., increasing levels of lighting, introducing rest pauses) on work output during the middle 1920s and early 1930s under the directorship of the Australian psychologist Elton Mayo (1880-1974). Since the 1970s, however, the interpretation of the effect has been a topic of some debate, culminating in the conclusion drawn by John Waller (2003) in his book Einstein’s luck: the truth behind some of the greatest scientific discoveries that the original work on which it was based is deeply flawed.
See Demand characteristics, ‘Screw you’ effect