Ethics of interaction design: influencing user choices

The more choices people have, the more likely they’ll choose something utilitarian over something hedonistic.


In an experiment by Aner Sela, Jonah Berger, and Wendy Liu, 20% of 121 participants chose low-fat ice cream when given a simple choice of two, but 37% chose low-fat ice cream when given a choice of ten. In this case, low-fat is seen as more utilitarian.

You’re probably not in ice-cream retail, so you may be interested to know that this finding also holds for hardware choices. When choosing one item from a selection of printers and MP3 players, the number of choices also influences what participants will choose. Given a simpler selection, two printers and two MP3 players, participants chose the MP3 player by about 3:1. However, just as an increase in ice-cream choices resulted in more utilitarian choices, so did an increase in the number of printers or MP3 players increased. When either the number of printers or the number of MP3 players increased to six (plus two of the other), the printers to MP3 players dropped 1:1. And, yes, in this experiment, the participants regarded printers as more utilitarian, and MP3 players as more hedonistic or fun.


 But it’s never that simple, because human brains can easily be manipulated.

The same researchers, in a further study, confirmed that people who earlier made a virtuous or selfless choice can more easily justify a subsequent hedonistic choice.

Offering users a virtuous choiceIf you ask visitors to an e-commerce web site to choose which charity should receive a portion of the site’s profits, the act of choosing between charity A and charity B probably increases the likelihood of a hedonistic subsequent choice.

You can combine all of this with other research findings. For example, when given a list of choices with the prices are in descending order (the most expensive item listed first), people are willing to consider spending 19% more, according to Cai Shun and Yunjie (Calvin) Xu.

Imagine the power of persuasion, or the influence, that an informed interaction designer can have on users, online customers, voters, and so on.

Clearly, there are ethical considerations. And the industry is starting to recognise this. For the first time this year, at the UPA 2009 conference in Portland, I saw conference presenters discussing ethics in interaction design. I’m sure the discussion is only beginning.