The Hawthorne effect is the tendency of people to change their behavior when they know they are being watched or studied. It takes its name from studies at Western Electric’s Hawthorne Works near Chicago, run between 1924 and 1933. A systematic review traces the term to a 1953 research-methods textbook, and how strong the original effect was is still debated (McCambridge et al., 2014).
How it works
Where you see it today
A team picked for an AI pilot gets new tools, attention and a sense of being watched. Early gains can reflect all three. Studies with comparison groups over longer periods, such as the staggered rollout of an AI assistant to customer-support agents studied by Brynjolfsson, Li and Raymond (2025), are a better guide than a launch-week showcase.
The effect now has a machine version. Needham et al. (2025) found that frontier language models can tell evaluation transcripts from real use better than chance, which they call evaluation awareness. If models behave differently when tested, benchmark scores may not match deployment.
Levitt and List (2011) recovered data from the first Hawthorne lighting experiments and found the striking patterns described in textbooks were not in the data, though they saw subtler signs of an effect. The lesson: check famous results before building on them.
A review of studies, mostly in health sciences, found that taking part in research does change the behaviors being studied, but little is securely known about when, how or how much (McCambridge et al., 2014). Always-on monitoring software raises the same question at work: people may optimise what is visible rather than what matters.
Hawthorne effect vs related ideas
How to use it
- Run AI and process pilots long enough for novelty to wear off, and compare with a team that did not get the change.
- Measure outcomes people cannot easily perform for an observer, such as error rates, retention or customer results.
- Separate the effect of attention from the effect of the tool: give the comparison group attention too.
- When you test AI models, include tasks that look like real use, not only obvious benchmarks.
- Treat dramatic textbook findings as hypotheses and check the original data where you can.
AI pilots and model benchmarks are both observed settings, so early numbers flatter. The Business Engineer reads enterprise AI adoption on what persists after the attention moves on.
Read: The State of Enterprise AI Adoption [Report] โExplore the platform โRelated: Pygmalion effect ยท Placebo effect ยท Demand characteristics ยท Goodhart's law ยท Scientific management
Frequently asked questions
What is the Hawthorne effect?
It is the tendency of people to change their behavior when they know they are being observed or studied, named after 1920s and 1930s studies at Western Electric's Hawthorne Works.
Is the Hawthorne effect real?
Research participation does seem to change behavior in some settings, but a systematic review found its conditions and size are poorly understood, and re-analysis of the original data found the classic story overstated.
Why does it matter for AI pilots?
Teams in a pilot get new tools and extra attention, so early gains can partly reflect being watched. Longer trials with comparison groups give a truer picture.
Can AI models show a Hawthorne-like effect?
Research suggests frontier models can often tell when they are being evaluated, which could make test behavior differ from real use.
Sources
- McCambridge, Witton & Elbourne (2014), Systematic review of the Hawthorne effect, Journal of Clinical Epidemiology
- Levitt & List (2011), Was there really a Hawthorne effect at the Hawthorne plant?, American Economic Journal: Applied Economics
- Needham et al. (2025), Large Language Models Often Know When They Are Being Evaluated, arXiv
- Brynjolfsson, Li & Raymond (2025), Generative AI at Work, Quarterly Journal of Economics
The full guide
The complete explainer, cleaned up and reformatted for mobile.
The Hawthorne Effect refers to an inclination of some people to work harder or perform better when they know they are being observed. The effect is most associated with those who are experiment participants, who alter their behavior due to the attention they are receiving and not due to any manipulation of independent variables. Therefore, the Hawthorne Effect describes the tendency for a person to change their behavior with the awareness that they are being observed.
Understanding the Hawthorne Effect
The Hawthorne Effect has also been discussed in the context of industrial and organizational psychology. Researcher Henry A.
Landsberger, who first described the effect, conducted landmark studies in the 1920s and 30s after being commissioned by an electric company to determine if there was a relationship between productivity and work environment.
During the studies, Landsberger examined aspects such as the timing of breaks, workplace lighting, and workday length.
In one particular study into the effect of decreasing light levels on worker productivity, Landsberger found that employees worked harder in response to the changes but then decreased their output once the test concluded.
It was later found that any change to the workplace caused an increase in productivity.
Many of these changes might appear to lower productivity at first glance, such as longer workdays or the elimination of work breaks.
The researchers concluded that employees responded to increased attention from supervisors and not from experimental variables.
Subsequent research into the Hawthorne Effect
Subsequent research into the Hawthorne Effect suggested that Landsbergerโs original results were somewhat overstated.
In 2009, a University of Chicago study went over the data and discovered that other factors played a role in employee productivity.
The study also found that many of Landsbergerโs conclusions were simply not supported by the data.
Nevertheless, the study did concede that the Hawthorn Effect was a real โ if not weak โ phenomenon.
Five years later, a systematic review published in the Journal of Clinical Epidemiology found the phenomena to exist across 19 different experiments.
The review also acknowledged that more research needed to be done to determine the mechanism(s) behind the Hawthorn Effect.
With that said, some factors which may influence productivity include:
Demand characteristics
Where study participants match their behavior to subtle clues a researcher may exhibit regarding the experiment hypothesis.
Novelty effects
Sometimes, performance increases because of the novelty associated with being monitored.
Performance feedback
In the original study, increased attention from researchers was thought to have increased performance feedback.
This in turn resulted in productivity improvements.
Principles of the Hawthorne Effect
- Observation Awareness: The key principle is that individuals modify their behavior when they are aware of being observed.
- Performance Improvement: The Hawthorne Effect often results in improved performance, as individuals strive to meet perceived expectations.
- Psychological Impact: It highlights the psychological influence of being the subject of study, leading to a sense of importance and engagement.
- Context Sensitivity: The Hawthorne Effect is context-dependent, varying based on the specific situation and individuals involved.
Advantages of the Hawthorne Effect
- Improved Performance: The Hawthorne Effect can lead to temporary improvements in behavior or performance.
- Engagement: It can enhance engagement and participation in research studies or workplace activities.
- Data Validity: Researchers may obtain more accurate data when participants are actively engaged in a study.
- Employee Morale: In workplaces, it can boost employee morale and job satisfaction.
Challenges of the Hawthorne Effect
- Temporary Effect: The changes in behavior are often temporary and may not reflect sustained improvements.
- Research Bias: Researchers must account for the Hawthorne Effect when interpreting study results.
- Generalizability: The extent to which the Hawthorne Effect applies can vary between individuals and contexts.
- Ethical Considerations: Some argue that the Hawthorne Effect involves a level of deception and raises ethical questions about consent in research.
When the Hawthorne Effect Occurs
- Observation: It occurs when individuals are observed, monitored, or made aware of being studied.
- Expectations: The Hawthorne Effect is more likely when individuals have expectations about the desired behavior or performance.
- Social Context: It can be influenced by social factors, including peer pressure or perceived societal norms.
- Individual Differences: Some individuals may be more susceptible to the Hawthorne Effect than others.
What to Expect from the Hawthorne Effect
- Behavior Modification: Expect individuals to modify their behavior, often in a positive direction, when they know they are being observed.
- Temporary Change: The effect is usually temporary and may not lead to lasting behavioral changes.
- Research Awareness: Researchers should be aware of the Hawthorne Effect and consider its potential impact on study outcomes.
- Engagement: In workplace settings, anticipate increased engagement and performance during periods of close observation.
Long-Term Impact of the Hawthorne Effect
- Research Consideration: Researchers must consider the Hawthorne Effect when designing studies and interpreting results.
- Organizational Dynamics: In workplaces, it may influence how organizations approach employee monitoring and engagement.
- Ethical Reflection: The Hawthorne Effect prompts ethical discussions about informed consent and the boundaries of observation in research.
- Behavioral Insights: The understanding of the Hawthorne Effect contributes to insights into how human behavior can be influenced by external factors.
The Hawthorne Effect in business
Here are some scenarios where the Hawthorne Effect may occur in business:
Management technique
Observation of employees is a double-edged sword.
Employees who know they are being observed may improve their performance because of increased accountability.
On the other hand, performance may decline if the employee perceives there to be an ulterior motive for the superior observing them.
Education
The Hawthorne effect has been proven to have very little impact on school-age children, but teachers observed by a camera or a person sitting in on their class tended to perform better.
Start-up growth
The Hawthorn Effect can also be used in new companies to encourage innovative ideas and collaboration.
Employee observation means opinions are heard and respected, which in turn invokes certain emotions that motivate the employee to strive for a common purpose.
Attentive observation can also be used to monitor employees as they collaborate in teams, with more productive team members tending to assume leadership of the group and deliver better outcomes.
Hawthorne Effect and Pygmalion Effect
Like the Hawthorne Effect, the Pygmalion effect is a psychological phenomenon where the person influenced can lead to a change in performance.
If leveraged adequately within organizations, this can lead to increased performance.
Case Studies
- Clinical Trials and Medical Research:
- A group of patients in a clinical trial might show improved health outcomes simply because they know they are under observation and not necessarily because of the treatment they are receiving.
- Patients might adhere better to medication schedules, maintain healthier habits, or even report symptoms more accurately when they know they’re being watched.
- Fitness and Physical Training:
- An individual may push themselves harder during a workout if they are aware that their trainer or a peer is watching them.
- Similarly, a person might eat healthier or adhere to a stricter diet if they are documenting their food intake or if they’re part of a weight loss program where others monitor their progress.
- Office Productivity Tools:
- Employees might work more diligently when they know that management has installed software to monitor computer usage, even if the software is benign or doesn’t actively track productivity.
- They might avoid personal internet browsing, take fewer breaks, or even work longer hours.
- Traffic and Driving Behavior:
- Drivers often reduce their speed or become more cautious when they see a police car, even if they aren’t doing anything wrong. They change their behavior due to the mere presence of potential observation.
- Similarly, placing a sign indicating that speed is being monitored, even without an actual speed camera, can reduce speeding incidents.
- Classroom Behavior:
- Students might behave better in a classroom setting when they know the principal or another authority figure is observing the class, even if that observation is passive.
- A teacher might employ varied teaching strategies or maintain a more structured classroom environment when being evaluated by superiors.
- Customer Service:
- Customer service representatives might be more polite, patient, and helpful when they know their calls are being recorded or monitored for quality assurance.
- Similarly, in-person service providers (like waitstaff in restaurants) might offer better service when they know a mystery shopper or reviewer is present.
- Environmental and Sustainability Practices:
- Individuals or companies might be more environmentally conscious when they know they are being observed or evaluated for sustainability practices.
- For example, a company might ensure recycling is properly done during an audit but be lax at other times.
- Home and Personal Behavior:
- People might clean their homes more thoroughly or maintain better personal habits when they know they have guests coming over.
- Someone might act more charitably or kindly in public settings when they feel they’re being observed, compared to when they’re alone.
- Competitions and Reality Shows:
- Participants in reality TV shows or competitions might act differently, either playing up certain aspects of their personality or hiding others, due to the knowledge of being observed by millions.
- Similarly, athletes might push themselves harder during a televised match or competition due to the presence of cameras and audience.
- Digital and Online Behavior:
- Internet users might adjust their online behavior, such as the language they use or the content they post, if they are aware that their actions are being monitored, even if just by algorithms.
- They might be more careful about personal information and their digital footprint when they know companies or authorities might be watching.
Key takeaways
- The Hawthorne Effect describes the tendency for a person to change their behavior due to an awareness of being observed. The phenomenon was first described by Henry A. Landsberger in a series of experiments in the 1920s and 30s.
- Subsequent research into the Hawthorne Effect suggested that Landsbergerโs original results were exaggerated. Indeed, the phenomenon may be supplemented by demand characteristics, novelty effects, and performance feedback.
- The Hawthorne Effect commonly occurs during employee-manager interactions. It may also increase teacher performance in the classroom and enhance ideation, leadership, and collaboration in young companies.
Key Highlights
- The Hawthorne Effect is the tendency for individuals to change their behavior when they know they are being observed.
- It was first described by researcher Henry A. Landsberger in a series of experiments in the 1920s and 30s.
- Landsberger conducted studies to explore the relationship between productivity and work environment for an electric company.
- The experiments involved manipulating factors like lighting, breaks, and work hours to observe their impact on employee productivity.
- Surprisingly, productivity increased whenever changes were made to the work environment, regardless of whether the changes seemed to improve or reduce working conditions.
- This led to the discovery of the Hawthorne Effect, where increased attention and awareness of being observed motivated employees to improve their performance.
- Subsequent research has suggested that the original results may have been somewhat overstated, but the Hawthorne Effect is still recognized as a real phenomenon.
- Factors that may contribute to the Hawthorne Effect include demand characteristics, novelty effects, and increased feedback and attention from researchers.
- In the business context, employees who know they are being observed may feel more accountable and work harder to meet expectations.
- However, if employees perceive observation as micromanagement, it may lead to decreased morale and productivity.
- In educational settings, the Hawthorne Effect has a positive impact on teacher performance, as they become more conscious of their teaching methods when being observed.
- In start-up companies, the Hawthorne Effect can be used to encourage collaboration and innovative ideas by valuing employee opinions and fostering a culture of open communication.
- The Hawthorne Effect is related to the Pygmalion Effect, where higher expectations for individuals lead to increased performance.
- Understanding and leveraging these effects can offer valuable insights into human behavior and help create more productive and supportive environments.
