OPINION5 April 2016

BE Bites: how to make numbers mean something

Behavioural science North America Opinion UK

Have you ever read a news article which quoted a lot of big numbers, yet you weren't really sure what they meant or how to visualise them? Crawford Hollingworth looks at how to add meaning to numbers.


Take the bold numbers in these news article extracts from the New York Times for instance:

  •          ‘Americans own almost 300 million firearms.’
  •          ‘The storm killed thousands of people in Honduras, left one million homeless...’ 
  •          ‘These planes are not allowed to fly below 400 feet.’

Are these relatively large or small numbers? Do you know how to react to them? How significant are these facts?

Many people struggle to answer these questions and interpret them. Dan Goldstein, Jake Hoffman and Pablo Barrio from Microsoft Research wanted to tackle this problem and make headlines and statements more meaningful by giving them some perspective. In recent research* (not yet published, but presented at a conference in November), they collected facts and statistics quoted in the news and crowdsourced for the best anchors and relative comparison points using volunteers from M-Turk.

They came up with a set of anchors or ‘perspectives’ as they called them. For the examples above they followed the original statement with the new anchor:

  •          ‘Americans own almost 300 million firearms. To put this into perspective, 300 million firearms is about 1 firearm for every person in the US.
  •          ‘The storm killed thousands of people in Honduras, left one million homeless... To put this into perspective, one million is about 12% of the population in Honduras.’ 
  •          ‘[These planes are not allowed to] fly below 400 feet. To put this into perspective, 400 feet is about the height of a 40 storey building.’

In following experiments they found that these ‘perspective’ clauses improved recall, estimations and error detection in readers, all proxies for better interpretation by readers.

Which type of anchors worked best?

  •          Like-for-like was most effective and useful for readers. For example, saying ‘Afghanistan is about the same size as Texas with about the same population'. Whereas saying that Kenya has twice the population of Texas would be less effective.  
  •          Personalised anchors – although anchors which have meaning for every person are good, it’s not always possible to find generalised anchors so it’s useful to tailor them according to someone’s location or culture. Interestingly the New York Times already uses a plugin which inserts relevant perspective information and anchors based on your location.

Although the focus here was on better journalism and news coverage, there are clear implications for any type of communication, whether to customers and consumers, researchers to respondents, or colleague to colleague.

For example, think hard about whether a recipient will be able to interpret and find meaning in a number or statistic you are giving them and if not, think about possible anchors you can use to illustrate a number and test them on others. Then follow the number with the phrase "To put this into perspective...".

If we are quoting figures on some form of communication a client is floating, would it help its impact to give people anchors to aid impact and comprehension? Whatever the number, it’s always possible to make it more meaningful for someone.

Crawford Hollingworth is founder of The Behavioural Architects