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  That Missing Piece: Playing to Our Need to Complete Sets 

Barasz, Kate; John, Leslie K.; Keenan, Elizabeth A.; Norton, Michael I.
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There's a simple way to increase people's effort levels, according to research by Kate Barasz, and co-authors. When tasks are grouped as being part of a set, people tend to feel the urge to complete that set. In experiments, this framing has been shown to motivate people to do more than they would otherwise, even with no additional reward.

Call it "pseudo-set framing." The concept draws on Gestalt psychology, which claims we are intrinsically drawn to completion, perceiving a whole as greater than its individual parts. So, grouping tasks into "pseudo" sets (i.e., even arbitrary ones) may tap into our desire for completion, providing a nudge at the moment of decision and affecting our choices.

The same idea applies to purchases. After all, how many times do you buy five cans when they are grouped as a six-pack, even with the same per-can cost?

Testing the Frames
In their article, published in the Journal of Experimental Psychology: General, co-authors Barasz, Leslie K. John, Elizabeth A. Keenan and Michael I. Norton carried out six carefully controlled studies to investigate how pseudo-set framing can work in various contexts.

Two studies looked at completing tasks with -- and without -- visual representations of progress as part of a pie chart, with four, five or seven pieces. In both cases, seeing progress as part of a pie chart motivated the study participants to put in more effort without more compensation.

"The pie chart intervention is a very simple idea, but it actually materially changes people's effort levels and makes them drop out at very predictable points," Barasz explains.

Another two studies looked at gambling and spending decisions. Presented with a potential "set of bonus winnings," participants in the gambling study risked more money than they did without the "pseudo set" incentive -- with other elements controlled. And when participants were asked how many beers they would hypothetically purchase at the store, the study looked to show the difference between a standard reference point (the six pack) and a pseudo set (here, a four pack). Specifically, participants were all reminded that beers often come in six-packs, yet when some were shown a four-pack container, they were more likely to opt to buy four beers.

Giving the Missing Piece
Another two studies tackled charitable giving, in situations where donors may already be motivated by the real-world impact of their efforts or money.

In one study, participants were asked to write holiday cards to seniors in nursing homes. They could write as many (or as few) cards as they wanted. When progress was measured in pseudo-batches of four cards, people were more likely to complete at least one batch. "Many more people finished four cards and they also finished more cards, on average, than the people who were not presented with batches," Barasz summarizes. Notably, this group did not rate the impact or meaning of the activity any higher than the other groups: the motivation to do more seems to come from a desire to complete the set.

Finally, there was a field study, working with the Canadian Red Cross on its 2016 online holiday campaign. By offering thousands of people the option to donate a full "set" of useful items, people donated more than they did when items were presented individually.

In all of these contexts, set framing can be a powerful tool to inspire and motivate workers, leaders and volunteers to get things done, and to commit more to the task or purchase at hand.

Methodology, Very Briefly
Four of the six studies recruited hundreds of participants each via Amazon's Mechanical Turk. They were paid small sums for their participation and sometimes for task results. The holiday-card-writing experiment involved 192 volunteers at an American university. Finally, working with the Canadian Red Cross, the researchers used Google Analytics to analyze thousands of responses and donations to a special campaign for the holidays in 2016.
This article is based on:  Pseudo-Set Framing
Publisher:  American Psychological Association
Year:  2017
Language:  English