James Swift

22 February 2021

Strategist’s Digest: What makes people share ads? 

Contagious digests the most interesting and relevant research from the world of advertising and beyond, because there’s just too much to read and too little time

Why Do People Share Some Advertisements More than Others? Quantifying Facial Expressions To Gain New Insights 

By Daniel McDuff, Microsoft, Jonah Berger, The Wharton School of the University of Pennsylvania

Give it to me in one sentence.

Ads that make people smile or wrinkle their nose (often in disgust) are more likely to be shared.

Give me a little more detail.

As the title gives away, the researchers were interested in which emotions were most likely to prompt people to share an ad. They created an algorithm that recognised five facial expressions: smiles (associated with joy), outer eyebrow raises (associated with surprise), brow furrows (associated with confusion), lip corner depressors (associated with sadness) and nose wrinkles (associated with disgust).

The researchers then deployed this algorithm on 2,106 participants (via a webcam) as they watched 10 video ads randomly selected from a pool of 230. All the ads had aired within the past 10 years and were from well-known brands.

After watching each ad, the participants were asked how likely, on a scale of 1-5, they would be to share it with someone else online.

The results showed that smiles were most strongly linked with sharing: a 30% increase in smiles was associated with a 10% increase in willingness to share.

Nose wrinkles (suggesting disgust) were also positively linked with sharing, but lip depression and brow furrowing appeared appeared to decrease their willingness to share.

The researchers also found that, in line with Daniel Kahneman’s ‘peak end’ rule, smiles raised near the end of a commercial (as opposed to near the beginning) had an even greater positive effect on willingness to share.

Why is this interesting?

According to the authors of the study, most of the previous work on facial expressions looked only at the link between positive emotions and sharing. As well as exploring how negative emotions encourage sharing (or don’t), the authors also appear to have created a way to conduct face expression studies at scale, since their algorithm could be trained (using supervised learning) to recognise facial actions by itself.

Any weaknesses?

It’s not exactly a weakness, but it’s worth stressing that this study measures ‘willingness to share’ rather than actual sharing. In the paper, the authors refute that participants confuse willingness to share with how much they liked an ad, but it’s still possible that the study misses something about real sharing behaviour.

Where can I find the whole report?

Here, and you can read an interview with one of the authors of the study, here.

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