Other people do

Apparently, if you ask someone in a survey about what they intend to do,  they are then more likely to do it.

The most-quoted example of this "mere-measurement effect" is canvassing for elections, which has been shown to increase the chance of people taking the trouble to vote by 25%. (Nudge: Improving Decisions and Health, Wealth and Happiness by Thaler and Sunstein)

This is a form of 'Nudge'.

I love Nudge Theory because it's so simple and has so many applications. It's also all about human behaviour. We all tend to be susceptible to suggestion and we just love to belong to something.

So when we want staff to fill in a survey, yes it's a good idea to ask nicely, and it helps to say what will be done with the responses. But it's also very powerful just to show that other people are filling it in. Other people are doing this, you are saying, so it's not such a risk.

That's the reason for those odd road signs urging you to "take your little home" simply because "other people do". I'm not sure this really works, as it still sounds preachy, but it might just be better than the blunt instruction "Keep Britain Tidy", which doesn't appeal to me on quite the same level.

So part of encouraging people to do something can involve establishing a norm, or the appearance of a norm. Yet it's really important to give people choice and to be honest with them. Promoting an option as a default, so people have to make an effort (however small) to do anything else, is obviously very powerful, but it can easily be misused. Think of all the pre-selected check boxes in online forms which you have to deselect to stop yourself being sent promotional material.