The wide adoption of social media has increased the competition among ideas for our finite attention. We employ a parsimonious agent-based model to study whether such a competition may affect the popularity of different memes, the diversity of information we are exposed to, and the fading of our collective interests for specific topics. Agents share messages on a social network but can only pay attention to a portion of the information they receive. In the emerging dynamics of information diffusion, a few memes go viral while most do not. The predictions of our model are consistent with empirical data from Twitter, a popular microblogging platform. Surprisingly, we can explain the massive heterogeneity in the popularity and persistence of memes as deriving from a combination of the competition for our limited attention and the structure of the social network, without the need to assume different intrinsic values among ideas. deas have formidable potential to impact public opinion, culture, policy, and profit 1 . The advent of social media 2 has lowered the cost of information production and broadcasting, boosting the potential reach of each idea or meme 3 . However, the abundance of information to which we are exposed through online social networks and other socio-technical systems is exceeding our capacity to consume it. Ideas must compete for our scarce individual and collective attention. As a result, the dynamic of information is driven more than ever before by the economy of attention, first theorized by Simon 4 . Yet the processes that drive popularity in our limited-attention world are still largely unexplored [5] [6] [7] [8] [9] [10] [11] [12] [13] [14] [15] . The availability of data from online social media has recently created unprecedented opportunities to explore human and social phenomena on a global scale 16, 17 . In this context one of the most challenging problems is the study of the competition dynamics of ideas, information, knowledge, and rumors. Understanding this problem is crucial in a broad range of settings, from viral marketing to scientific discovery acceleration. Aspects of competition for limited attention have been studied through news, movies, and topics posted on blogs and social media 10, 11, 13 . The popularity of news decreases with the number of competing items that are simultaneously available 8, 18, 19 . However, even in the simplified settings of social media platforms, it is hard to disentangle the effects of limited attention from many concurrent factors, such as the structure of the underlying social network 7, 13 , the activity of users and the size of their potential audience 19 , the different degrees of influence of information spreaders 20 , the intrinsic quality of the information they spread 21 , the persistence of topics 22, 23 , and homophily . To compound these difficulties, social networks that host information diffusion processes are not closed systems; exogenous factors like exposure to traditional media and their reports of world events play important roles in the popularity and lifetime of specific topics 10, 25 . Another example of our limited attention is the cognitive limit on the number of stable social relationships that we can sustain, as postulated by Dunbar 26 and recently supported by analysis of Twitter data 27 . We propose an agent-based model to study the role of the limited attention of individual users in the diffusion process, and in particular whether competition for our finite attention may affect meme popularity, diversity, and lifetime. Although competition among ideas has been implicitly assumed as a factor behind, e.g., the decay in interest toward news and movies 28, 8, 10 , to the best of our knowledge nobody has attempted to explicitly model the mechanisms of competition and how they shape the spread of information. In particular, we show that a simple model of competition on a social network, without any further assumptions about meme merit, user interests, or explicit exogenous factors, can account for the massive heterogeneity in meme popularity and persistence. Here we outline a number of empirical findings that motivate both our question and the main assumptions behind our model. We then describe the proposed agent-based toy model of meme diffusion and compare its
Still, the abundance of information to which we are exposed through online social networks and other socio-technical systems is exceeding our capacity to consume it REF .
Competition among memes in a world with limited attention
Scientific Reports
Scientific Reports
Computer Science Medicine