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Discrete Choice in a Police Lineup

police lineup discrete choiceThe Economist reviewed a study by Dr. Neil Brewer about effective police lineups which I think had implications for Market Research. Like researchers, police typically like to encourage witnesses to take their time to ensure they are making the correct choice. This makes logical sense, more time, means more thinking which naturally should lead to better results. Sadly, Dr. Brewer found otherwise.

He had volunteers view short films which detailed mundane scenes of everyday life and a crime (shoplifting, car theft, etc). Later (some minutes later, some a week), they were asked to identify the criminal from a group of 12 pictures of “suspects”. Half were given 3 seconds to evaluate each picture and asked how confident they were of their choice. The other half were given as much time as they wanted. The results showed that the group that had the limited time was correct 67% of the time. The group with more time was only correct 49% of the time.  

There are lots of reasons why this might have happened. First, the half given three seconds were told they would have three seconds and after two seconds a buzzer sounded telling them they had 1 second to enter an answer (if they failed to do so, the next picture appeared automatically). This is similar to gamification efforts that show that the imposition of a time limit causes people to be more focused. So, it is possible that the time limit simply meant people were paying closer attention.  

Second, Behavioral Economics tells us that our thinking can be divided into “system 1” (intuitive and fast) and “system 2” (slower, conscious) type thinking. This would seem to indicate that “system 1” thinking is better for making a choice like this. Perhaps more thoughtful thinking brings various prejudices and biases into the equation.

These and other explanations should give researchers a lot to think about:

  • Does gamification lead to more engagement and thus better outcomes?
  • When should we limit the time respondents have to choose an answer?
  • Can we determine up front which questions need “system 1” thinking?

Like Dr. Brewer, market researchers should be experimenting with techniques that engage respondents in the same way that they will be engaged in the market place. Discrete Choice, Max Diff and various other choice techniques are fantastic tools today, but the potential for improvement needs to be explored. For example, tools that encourage both types of thinking, such as our own Smart Incentives (idea generation and gamification tool), should be deployed more frequently. Doing so will ensure market research goes beyond just staying relevant…it will make us indispensible.  

President, TRC

Rich brings a passion for quantitative data and the use of choice to understand consumer behavior to his blog entries. His unique perspective has allowed him to muse on subjects as far afield as Dinosaurs and advanced technology with insight into what each can teach us about doing better research.  


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Guest Tuesday, 27 October 2020

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