New nudging papers keep on appearing in the literature. I just read a very interesting nudge experiment conducted by Janet Schwartz, Jason Riis, Brian Elbel and Dan Ariely. It is inspired by the sentence 'Do you want to supersize your order?’ that you could have heard at McDonalds before negative publicity (including the movie ‘Supersize me’) made an end to this practice. Such a verbal prompt, however, is still being used at station kiosks (‘Do you want something to eat with your coffee?’) and some other shops.
The basic idea behind their experiment is to simply ask consumers at a fast food restaurant if they would like to downsize their side dish (with and without a small incentive). Usually, less than 1% of the customers at fast food restaurants request a smaller portion size. The intervention was successful: between 13 and 44% of the consumer accepted the offer, regardless of whether they were also offered a discount of 25 cents.The authors also compared this intervention with a calorie labelling intervention and showed that only the offer to downsize had a signficant effect on the number of calories consumers ate.
This example of verbal encouragement can give consumers just that little push to make a different choice and exercise self-control. Consumers are likely to give in to such little pushes because they implicitly think that saying ‘yes’ is an appropriate response. When you ask people for an active response (always respond verbally or in writing) they are more likely to respond positively than when you ask for a passive response (only respond in case of yes).