Hawthorne Effect

Also known as: Observer effect

The Hawthorne effect is a phenomenon where people change their behavior simply because they know they are being watched. The act of observation itself alters the reality being observed.

Social Biases

2 min read

observational Evidence


Hawthorne Effect

The Psychology Behind It

Named after the Hawthorne Works factory in Chicago, where experiments were conducted in the 1920s. Researchers wanted to see if better lighting improved worker productivity. They increased the lights; productivity went up. They decreased the lights; productivity still went up. They realized that the workers weren't responding to the lights; they were responding to the attention.

When we know we are being watched, we perform. We work harder, smile more, and follow the rules. This is a form of "social desirability bias." We want to look good for the observer.

Real-World Examples

The "Boss is Watching" Effect

Productivity in an office spikes when the manager walks into the room. It drops when they leave. The behavior is not a reflection of the workers' natural state, but of the surveillance.

Medical Adherence

Patients in clinical trials take their medication more regularly than patients in the real world because they know they will be tested and asked about it. This makes drugs look more effective in trials than they are in practice.

Reality TV

People on reality shows act in exaggerated, dramatic ways because they are aware of the cameras. The "reality" is constructed for the audience.

Consequences

The Hawthorne effect can lead to:

  • Temporary Improvements: Interventions (like a new management style) seem to work at first, but the effect fades once the novelty and observation wear off.
  • Inaccurate Data: We fail to measure typical behavior because the measurement process itself changes the behavior.
  • Surveillance State: Management might rely on constant monitoring to boost productivity, which can lead to stress and burnout.

How to Mitigate It

Observe without being seen.

  1. Unobtrusive Measures: Collect data from existing logs (e.g., computer usage, sales figures) rather than standing over the worker's shoulder.
  2. Habituation: If you observe for long enough, people eventually forget you are there and return to their normal behavior. The first week of data is useless; the second month is real.
  3. A/B Testing: Test changes (like a website design) on users who don't know they are part of a test.

Conclusion

The Hawthorne effect is the Heisenberg Uncertainty Principle of human behavior: you cannot measure a person without changing them. It reminds us that attention is a powerful drug, and people behave differently when they are on stage.

Mitigation Strategies

Naturalistic Observation: Observe subjects in their natural environment from a distance or via hidden means (ethically approved) to capture true behavior.

Effectiveness: high

Difficulty: moderate

Potential Decision Harms

Managers implement a new policy, see a temporary spike in productivity (Hawthorne effect), and wrongly conclude the policy is a success.

major Severity

Teachers perform better during an evaluation observation, masking their usual poor performance.

moderate Severity

Key Research Studies

Management and the Worker

Roethlisberger, F. J., & Dickson, W. J. (1939) Harvard University Press

The seminal text describing the Hawthorne experiments and the discovery of the social aspects of work performance.


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