Back to top

Nudging and Complexity

In 1917 a regional U.S. traffic administration had a white centreline painted on a stretch called Deadman’s Curve on a highway in northern Michigan, with arrows inviting people to stay on one side of the road. At a time when there were almost no lines on roads, no rules as to the meaning of these lines, and no laws punishing those who ignored them, this was one of the first modern government’s nudges. In recent years, government nudges have become very popular, especially in Anglo-Saxon countries. And they are effective. Let’s have a look at just a few examples.

  • Many people pay their taxes late, and usually the authorities need to send them several reminders. If such a letter contains the phrase “most people in your area pay their taxes on time and you are one of the few yet to do so”, about 20% more people comply.
  • Job centres have an effectiveness problem, because job seekers often don’t show up to the interviews arranged for them. If the reminder addresses the job seeker by name, wishes them good luck, and bears the name of the social worker who has fixed the appointment for them, three times as many people actually show up for the interview.
  • When they painted a big picture on the stairs of a train station, twice as many people took the stairs instead of the escalator.

What is essential about a nudge is that the desired behaviour happens, on the individual level, as the result of choice. It needs to be easy to avoid, there must be no force or constraint applied, and no incentive. Only then is it a nudge. As Richard Thaler and Cass Sunstein, who won a Nobel prize for their work on nudging, put it: “Putting fruit at eye level counts as a nudge. Banning junk food does not.”

From a complexity perspective, this element of choice makes nudges interesting. Instead of a constraint imposed on a system, a nudge is a small tap, and therefore a small amount of energy, applied on a high-potential leverage point in the disposition of a system. A nudge works because it triggers emergent behaviour. In gardening we learn quickly that grass does not grow faster when you pull at it. You influence the conditions such as water, sunlight, soil structure, fertiliser, and millions of grass blades do indeed grow faster as a reaction to your influence. The system does most of the heavy lifting itself. The tipping points that a nudge searches and addresses can be extremely small in comparison to their effect. A colleague once worked on a consulting mandate for a hospital. One of the problems was the storage and preparation rooms in the operating suite. When a team leaves the operating room, they are usually in a hurry to leave the equipment. Not surprisingly, later teams have trouble finding the correct items. The solution consisted in colour-coding storage areas, and colour-coding equipment accordingly. There was no obligation to put equipment at the place with the correct colour code. And yet the number of misplaced items went almost down to zero. A well-placed nudge is an enormous potentiator of energy.

The downside of this advantageous scaling of energy is that no nudge is guaranteed to work – if you define the term “work” in terms of “whenever applied, always fully solves the problem”. In complex environments, this binary way of thinking, not solved to solved, success to guaranteed equal success, most often is not accurate. We need to be content with less. Nudges are worthwhile instruments even if we haven’t found that perfect potentiator. A nudge is good enough to try if it produces an improvement in many cases, not in all, and if that effect justifies the effort. In the case of government nudges, the sheer number of instances, of late taxpayers, undisciplined jobseekers, or inattentive drivers, translates this uncertainty into a statistical percentage. If you affect millions of people, even a one percent improvement justifies a certain effort. Once we move to more intimate situations, our decision to try a nudge must take into account that in this one case before us it could as well fail.

However, this non-compulsory, or non-deterministic nature of the nudge, its contingency connected to the element of choice, has further desirable implications. In the example of grass, we tend to imply a certain sense of necessity, of passivity on the side of the plants’ reactions. If not all plants react to the fertiliser, we suppose that the micro-condition of the exceptions were different. If we talk of humans instead of plants, we attribute divergent behaviour to choice. The nudge’s influence on the conditions – in the language of nudging: on the choice architecture – is met with the element of free will. Not all people choose to react the same way to the same conditions. But this means that people reacting to a nudge, knowing that they have a choice, usually feel a sense of ownership towards their action. And this has an influence on how they adapt and persevere in the face of changing and difficult circumstances.

In the world of health and safety, this sense of ownership is important because those who point things out to people, are usually not present when the unpredictable high-risk situation arises. Many mining and manufacturing companies have placed mirrors at key points, stating “this person is responsible for your safety”. Nudges can be our last reach out to influence a person’s state of mind, before they descend into the shaft, start operating the dangerous machine, or simply, move into that area where they alone decide what to do. After they cross that threshold, their state of mind is the only thing that makes them prefer one kind of behaviour over another. The nudge tries to impact that state of mind.

  • What We Do

    Palladio Trusted Advisers are a small group of professionals dedicated to developing organisations and their leaders in complex and dynamic environments.


  • Contact

    Trusted Advisers
    Bachlettenstrasse 66
    4054 Basel

    +41 78 783 72 44

©2020 Bernhard Sterchi, Palladio Trusted Advisers AG.
All right reserved.