James Swift

8 March 2021

Strategist’s Digest: When advertising beats influence 

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

Photo by NASA on Unsplash

Network hubs cease to be influential in the presence of low levels of advertising 

By Gabriel Rossman and Jacob Fisher

Give it to me in one sentence.

You don’t need well-connected influencers to spread new ideas and behaviours when you advertise.

Give me a little more detail.

Researchers Gabriel Rossman and Jacob Fisher created computer simulations that mimicked how information and ideas spread among networks of people. Some of the simulations were randomly generated and others were based on real-life networks, like email data from the Democratic National Committee and Enron, and Twitter.

First, the researchers looked at what happens when information is spread solely through word of mouth. In those instances, well-connected people did play a significant role in hastening the spread of information, and the larger the network, the more influence they exerted.

But when the researchers introduced just a little bit of top-down communication (ie, advertising) into the simulation, the importance of influencers fell away. When advertising was just 0.26% as strong as word of mouth, a well-connected individual was no more influential than someone at the periphery of the network.

Rossman offered Contagious a helpful analogy to explain the effects: ‘Suppose that a rumour starts in the UCLA sociology department. If I am the only sociologist who has friends in the anthropology department then I'm really important since I can prevent the rumour from spreading to anthropology.

‘Starting the rumour with me would make it spread much faster than starting with one of my colleagues at random. Now suppose that while academics love gossiping, we also occasionally read flyers we see on the bulletin board of the social sciences building. If on the same day the rumour starts there’s a flyer with the rumour posted to the bulletin board, then almost every anthropologist can ignore the flyer but as long as even one of them reads it then the rumour can leapfrog over me and I am no longer structurally important for the flow of information between sociology and anthropology.’

Why is this interesting?

The idea that influential people (or ‘key nodes’ to use the technical jargon) have the power to change the behaviour of entire social systems is at the heart of social network analysis. But a lot of the research that informed this idea relied on artificial conditions, in which word of mouth was the only way that information spread.

Rossman and Fisher’s experiment recreates the spread of information in an environment that better reflects the real world. And according to the authors of the study, the results suggest that ‘advertisers or public health officials who are planning a campaign should consider that advertising can also promote network-based spread and may do so more efficiently than identifying and recruiting a highly central seed node.’

But do not interpret this as ‘influencers are bad’. ‘We’re arguing against optimal seeding by network structure, not sponsored content with professional social media personalities,’ says Rossman.

Any weaknesses?

While the experiment does aim to reflect the spread of information in the real world it is still, says Rossman, ‘a very streamlined abstracted version of reality’.

‘We made various simplifying assumptions such as that you either have a tie or you don’t, ties are symmetrical, once you adopt a widget/idea you maintain it forever, etc,’ he adds.’

Where can I find the whole report?

Here. It’s free but it’s also complex. You can read a news release about the study here.

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