When it comes to using a social media service like Facebook, people are more influenced by what their friends are doing with it than lists suggesting what is most popular.

That is the clear finding of a new study by researchers at the University of Limerick, working with scientists at the University of Oxford and Harvard School of Public Health.

The team developed a mathematical model to study people's behaviour on social networks, particularly the level of influence their friends were having on their behaviour versus reliance on so-called "best-seller" lists. 

These are lists that show which apps, for example, are being downloaded most by the users of a particular service.

The scientists incorporated data around the installation of apps available to Facebook users into their model, and found that recent adoption by friends had a stronger influence on whether people downloaded certain apps than the influence of the list of most popular apps available on the network.

According to the research, which was published in the Proceedings of the National Academy of Sciences,  the tendency towards "copycat" behaviour in humans is strong, to the extent that we can be influenced by what others do over a relatively short period of time.

The researchers used supercomputers at the Irish Centre for High-End Computing, to run thousands of simulations in which they varied the relative dominance of the two influences.

15,000 hours of computer processing was used to best match the results of the simulations with the characteristics of app installation that were observed in the earlier empirical study.