<P> The Hawthorne effect (also referred to as the observer effect) is a type of reactivity in which individuals modify an aspect of their behavior in response to their awareness of being observed . The original research at the Hawthorne Works in Cicero, Illinois, on lighting changes and work structure changes such as working hours and break times was originally interpreted by Elton Mayo and others to mean that paying attention to overall worker needs would improve productivity . Later interpretations such as that done by Landsberger suggested that the novelty of being research subjects and the increased attention from such could lead to temporary increases in workers' productivity . This interpretation was dubbed "the Hawthorne effect". </P> <P> The term was coined in 1958 by Henry A. Landsberger, when analyzing earlier experiments from 1924--32 at the Hawthorne Works (a Western Electric factory outside Chicago). The Hawthorne Works had commissioned a study to see if their workers would become more productive in higher or lower levels of light . The workers' productivity seemed to improve when changes were made, and slumped when the study ended . It was suggested that the productivity gain occurred as a result of the motivational effect on the workers of the interest being shown in them . </P>

N the first set of hawthorne experiments dealing with lighting the main conclusion was that