The Hawthorne Experiments: Management Takes A New Direction

General  Electric, the major manufacturer of light bulbs, had preliminary evidence that better lighting of the work place improved worker productivity, but wanted to validate these findings to sell more light bulbs, especially to businesses. GE funded the National Research Council (NRC) of the National Academy of Sciences to conduct an impartial study. AT&T's Western Electric Hawthorne plant located in Cicero, Illinois, was chosen as the laboratory. Beginning with this early test, the “Hawthorne Experiments” were a series of studies into worker productivity performed at the Cicero plant beginning in 1924 and ceasing in 1932.

Illumination Studies, 1924 -1927

The earliest experiment (1924) was conducted by the NRC with engineers from MIT. The study would end in 1927 with the NRC abandoning the project. The group examined the relationship between light intensity and worker efficiency. The hypothesis was that greater illumination would yield higher productivity.  Two work groups of female employees were selected for  “control” and “experimental” groups. By comparing the changes on worker productivity by manipulating lighting in the experimental group with the production of the control group, the researchers could validate and measure the impact of lighting.  The study, however, failed to find any simple relationship as poor lighting and improved lighting seemed in increase productivity. Indeed, in the final stage, when the group pretended to increase lighting the worker group reported higher satisfaction.

The preliminary findings were that behavior is not merely physiological but also psychological. This was a break with the Scientific Management school that saw work productivity as “mechanical”, and led to the decision to learn more about worker behavior. George Pennock, Western Electric’s superintendent of inspection suggested that the reason for increased worker productivity was simply that the researchers interacted with the female employees; and, this was first time any one had shown an interest in the workers. Basically, the workers were trying to please the researchers by continuing to increase their output and report satisfaction in the study, no matter what the intervention was. Later, the phenomenon of a researcher corrupting an experiment simply by his presence would be termed the “Hawthorne effect”. 

Relay Assembly Test Room Experiments, 1927-1929

The NRC started an experiment to probe the unexpected findings of the Illumination study but would depart in 1927, at which time Western Electric continued the project drawing on support from Harvard researchers. An experimental group was established of five young women from the Relay Assembly room of the plant. The experiments involved the manipulation of a number of factors, to include pay incentives, length of workday and workweek, and use of rest periods, to measure impact on productivity and fatigue. Again, the relationship between pay, incentives, rest, and working hours seemed to have little effect on productivity, even when the original, more demanding conditions were re-implemented. 


Mica-Splitting Test group, 1928 – 1930

Disturbed by the inconclusive evidence that rewards and incentives improved worker performance, a second experiment was conducted to look only at this relationship using workers in the Mica-Splitting Room. In his experiment the workers’ piece wages were held constant while work conditions were varied.  Productivity increased by about 15%. The researchers concluded that productivity was affected by non-pay considerations. Members of the research team began to develop the theory that social dynamics were the basis of worker performance.

Plant-wide Interview program, 1928-1931

As early findings indicated that concern for workers and willingness to listen impacted productivity, Western Electric implemented a plant-wide survey of employees to record their concerns and grievances. From 1928 to 1930, 21,000 employees were interviewed. This data would support the research of the Harvard team for years and lead them to conclude that work improved when supervisors began to pay attention to employees, that work takes place in a social context in which work and non-work considerations are important, norms and groups matter to workers.

Bank Wiring Observation group, 1931-1932

The final Hawthorne experiment was conducted studying 14 male workers assigned to the Bank Wiring factory. The objective was to study the dynamics of the group when incentive pay was introduced. The finding was that nothing happened! The work group had established a work “norm” – a shared expectation about how much work should be performed in a day and stuck to it, regardless of pay.  The conclusion: informal groups operate in the work environment to manage behavior.


Importance of the Hawthorne Plant Studies

Despite modern criticism that the research was flawed and that incentives played a larger role in improving worker productivity than the Hawthorne plant researchers concluded. These studies changed the landscape of management from Taylor’s engineering approach to a social sciences approach. Worker productivity would, henceforth, be interpreted predominately in the United States in terms of social group dynamics, motivation, leadership, and “human relations”.  The practice of management could not be the aloof technician of Taylor’s Scientific Management, designing the job, selecting and training the “right” worker, and rewarding for performance. The manager was an immediate part of the social system in which work is performed, responsible for leading, motivating, communicating, and designing the social milieu in which work takes place.

The studies also developed the scholars that would continue to influence the American way of thinking about management at Harvard Business School and elsewhere. Included among these researchers were:

Elton Mayo came to Harvard from Wharton where as a psychologist he had researched the impact of social and home life on worker performance. At the Harvard University School of Business his reputation led him to consult with the FBI and the movie industry. Mayo’s reporting of the Hawthorne experiments became the most influential in that he laid out a programmatic interpretation, which would be called the “Human Relations” approach that dominated management thinking until the 1950’s. Mayo’s views lead to the construction of manager as a leader supported by knowledge and skills to build social cooperation. 

Fritz Roethlisberger and W.J. Dickson were the first to publish comprehensive findings of the Hawthorne experiments in 1937 and authored Management and the Worker in 1939, a comprehensive statement of the research and findings.  Roethlisberger, educated as an engineer, started the Harvard Industrial Research Department, was a lead researcher in the Hawthorne project and a leader in the Human Relations movement. Dickson was Chief of Employee Relations Research Department at the Hawthorne plant and an instrumental contributor to the project. 

W. Lloyd Warner, an anthropologist who designed the group experiments, pioneered the field of social anthropology at Chicago and Michigan.  His work includes classics in the American class system and race.

L.J. Henderson a chemist and physiologist in charge of the Fatigue Laboratory at the Harvard Business School provided a theoretical foundation to the research. He would contribute to the development of “systems theory”, influencing management theorists Chester Barnard and George Homans. He became the first president of the History of Science Society.

This group of scholars permanently influenced the study of management and the development of Organizational Behavior as a discipline.