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Is the Hawthorne Effect really just Heisenberg’s Uncertainty Principle for the common man?

The Hawthorne Effect was first described by psychology researcher Henry Landsberger in the fifties when he analysed work done decades earlier at Western Electric’s Hawthorn Works near Chicago.

Western Electric ran a study to see if its workers would become more productive if the light levels were raised. This did indeed happen, there was a significant increase in productivity when the lighting in the workplace was made brighter, even if only a little bit brighter, although after some time productivity gradually dropped again.

So the experimenters reduced the light levels again by the same amount they had originally put them up.

I suspect you’re ahead of me on this one… when the light levels were reduced the productivity went up again!

This has become known as the Hawthorne Effect – people who are being studied improve their performance simply because they are being studied; someone is measuring them, assessing them, taking an interest in them, or otherwise giving them unusual attention, and it makes them change their behaviour.

It’s a bit like driving a car when a policeman is following you – you become really careful and precise in your use of the mirror, indicators, lane discipline, and so on!

The Hawthorne Effect doesn’t just apply to lighting; far from it. It applies to many changes or initiatives such as improved cleanliness or workplace layout (5S), new working methods and processes, changed organisational structures, training and development, TQM programmes, and a host of other things that management does to try to improve productivity.

So why do I mention Heisenberg?

In quantum mechanics, the Heisenberg Uncertainty Principle explains how certain pairs of physical properties of subatomic particles cannot be known at the same time. So, for instance, if you know an electron’s position you can’t know its velocity and vice versa. Some scientists say this is a fundamental characteristic of nature, it simply isn’t possible to know both things at the same time; this is where quantum mechanics becomes rather surreal for the layman!

However, for others scientists it is more an indication of the effect that the experimenter has on the experiment – the act of measuring velocity means that you destroy the information about its position, and if you do an experiment that determines the electron’s position at a moment in time then the information about its velocity is lost.

In other words, the observers contaminate the experiment; their presence affects the outcome. That is what happens with the Hawthorne Effect.

It also has a something in common with the Placebo Effect in which, if a patient simply believes they are receiving a certain type of medication or treatment, their medical conditions improve, even if the medication or treatment is a dummy that can be shown to have no effect on the condition being treated.

So what does all this have to do with your management or quality improvement initiatives? Well, it means that you may want to adopt a sceptical attitude towards your results.

You should be making changes and evaluating the result as part of your philosophy of Continuous Improvement but, when you do so, ask yourself if the improvements are not so much because of what you have done, but simply that you have done something.

Keep an eye on those results; if they drop back when you stop paying them as much attention, you may be experiencing the Hawthorne Effect.

The late Sir John Harvey-Jones said “Management is not about the preservation of the status quo. It is about maintaining the highest rate of change that the organisation and the people within it can stand”. Maybe one benefit of this potentially disruptive strategy is that you ride the wave of the Hawthorne Effect; if people are frequently having the right sort of attention given to them, they may raise their performance to match.

Who cares if it’s the Placebo Effect or the common man’s manifestation of Heisenberg’s Uncertainty Principle, an improvement is an improvement!

2 comments to Is the Hawthorne Effect really just Heisenberg’s Uncertainty Principle for the common man?

  • Chris

    Sometimes people get the uncertainty principle mixed with the entanglement. I’m not sure what you’re doing here but when you say information is destroyed I have to say that I do not agree.
    Just because I have not taken samples doesn’t mean the information was destroyed. it just means that I have ignored something going on in the background (it’s still happening). So, if I can only take 30 samples in an hour I have to decide when to take them and what to measure. The more I know about one the less I know about another. (if only I could be in two places at once.)
    I understand that the more we focus on one property of a process, the more that process is likely to be altered (Hawthorn effect). I also understand that looking at that one property or focussing on it blurs ones knowledge of everything else (Heisenberg uncertainty).
    It’s very statistical but statistics doesn’t change the outcome. In fact we are not actually trying to determine the exact property when we are measuring. We are trying to predict what it will be next time, we are trying to determine its exactness. When something unpredictable happens then we know that there is a force atypical of the system that caused it.
    Then how do we discuss the two concepts together? It’s enough to say they are “Two peas in a pod”, but at the same time to keep them distinct so that we know we cannot look at one entirely and perceive the other simultaineously.

    I leave with two of Demming’s quotes, “All management is prediction”, and “Management creates quality.”

  • Tom G

    Chris, you’re absolutely right of course in the normal (non-quantum) world of course. Taking 30 samples on a production line doesn’t (usually!) fundamentally destroy information. In the quantum world you do get this type of effect.

    My analogy was really a broader one as we don’t tend to bump into quantum effects day-by day (well I don’t anyway!); it’s all about being aware of the effect that the experimenter can have on the experiment which is the theme that Hawthorne has in common with at least the the populist interpretation of Heisenberg, if not the quantum mechanical interpretation. I do like your comment about two peas in a pod, they are different concepts of course but they have that aspect in common.

    And two good Deming quotes, too! Many thanks for taking the time and trouble to comment.


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