Nudging for One: Dipping headlamps

Richard Thaler talks about policies which can ‘nudge’ people into ‘good’ behaviour. I don’t see why individuals can’t find ways to encourage others to behave well too.

Whilst driving around South Africa I noticed that some people dim their full beams at night and others don’t. How could I nudge people into good behaviour? The answer seems to be to make sure that the other driver sees me dimming my own lights.

On a long drive home last night, whenever I waited to dim at a point when they were sure to see me, 100% of drivers also dimmed their lights. When I did it before, however (e.g. coming around a corner or over a hill), a lot of other drivers either left their lights on full beam or flashed me to remind me to dim my own lights, even though they were already dimmed.

There is obviously often some doubt as to what the other person has done and a sense of fair play says that you will not dim your lights unless the other driver does too – it seems that there are two Nash Equilibriums possible.

I think that there is something additional happening too. By dimming your headlights first, you are setting a sort of ‘social norm’ in the situation. Deviating from a social norm costs most people psychologically, either because they feel bad about behaving in a way contrary to the norm established by society or because they are ‘punished’ (in some sense) if they do (no one likes their neighbours to ‘tut tut’ them).

If this is (partly) true, then it suggests that people can be nudged into other ‘good’ behaviour – for example, recycling – if it can be made to seem like a social norm. Note, it only needs that people believe it to be a social norm for it to actually become one (self-realising expectations).

If you show your neighbour you are recycling or giving to charity or voting, you might nudge others into doing the same.

Herd behaviour. When I was 16, I worked in a shop where I had to ask customers if they wanted to buy stamps. I noticed that if one person said yes, many others in the line also would. Similarly, if one looked at me with disdain (‘of course I don’t want any bloody stamps – I would have asked if I did’) so would other people in the queue.

I sometimes try to put that into practice in South Africa*. When I see tourists mulling over whether or not to make a purchase of some tourist tat (or something nice), I like to encourage them by buying something small. Sometimes, just hanging around a stall seems to attract people (it’s the ‘would you go into an empty restaurant?’ thing).

* I say South Africa, not Lesotho because I see so few tourists in Lesotho.