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Page Title - projects
Phase 2: Theme C - Innovations in complex social networks: Project C003
Fashions and science: The complex effects of random copying versus independent thinking
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Alex Bentley (Department of Archaeology & Anthropology, Bristol University)

PROJECT FUNDING: Cards Against Humanity
fridge freezers

Research old and new demonstrates that people often copy the tastes of one another rather than make independent judgments. It is crucial issue because, whereas independent decisions usually retain a rational basis, copying can lead to unpredictability in collective behavior.

Initially, we showed that a simple model of random copying predicts the way popularity is distributed among Neolithic pottery decorations modern baby names, dog breeds, and even in academic publishing. We recently observed that modern fashion changes at a remarkably constant rate, as documented by constant turnover on pop charts. In agreement with the real-world data, a copying model predicts continual turnover, dependent on the amount of innovation. Hence, while rational decisions should settle on an “optimum” behavior, random copying leads to consistent change. This can be used to predict change rates and distinguish copying from independent decision-making in collective behavior.

This latest project concerns fashion versus independent thinking in modern science. Ideally, science is the systematic process of testing multiple hypotheses, but as practiced by real people, it is also distinctly social. Academics do their research within complex social networks, and are prone to copy ideas from one another. We all have our opinions as to what constitutes trendy ideas versus valid research, yet there is yet little means of evaluating this objectively. Through database research, I plan to develop means to characterise the modern scientific process in terms of a continuum between copying fashionable ideas at one extreme, and independent selective testing of hypotheses at the other.

This research has helped to guide students into job opportunities and/or graduate research, through study projects on popular fashion change, social networking, cyberspace communities, computer simulation or quantitative analysis of material culture. There are also chances to work synergistically with real-world professionals to achieve unique insight.

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During Phase Two of the Centre, this project contributed to the broader development of cultural evolutionary science by (a) developing a powerful general model of cultural drift (b) testing this model against a considerable number of different case studies, including the use of academic keywords as part of the focus of the specific project and (c) integrating the model of cultural drift with other existing models of cultural evolution, as functions of the scale of population and redundancy of choice. Generally, the discovery through this project is that the ‘neutral’ model of undirected social influence predicts several diagnostic empirical patterns—long tail, continual turnover, stochastic change—that can be tested against popularity data. We find that it applies best to large, interactive populations confronting many similar options. In such populations, the overall direction of copying is indiscernible, with so many similar choices and so many different individual copying biases that they collectively pattern as if they were undirected, or ‘neutral’.

Behavioural economist Herb Gintis describes a major problem in that each of the social sciences—economics, anthropology, sociology, and psychology—has a different basic assumption about human behavior. The difference is particularly acute between the ‘neutral’ model developed in this project, versus classic approaches centered on individual behavior—economics, evolutionary psychology, and game theory— that have provided fundamental insights about how costs and benefits can be good predictors of evolved adaptations to the natural environment. By calibrating the neutral model to different datasets (not just academic projects but also projects for the Gates Foundation and the U.K. Department of Health), this project found that a rough but useful distinction between social influence that is directed in some way versus copying that is undirected (i.e. neutral), at least at the population scale. In view of these different processes and different scales, determining which predominates in a certain situation becomes an empirical question that we can now discern by seeing which model best fits the data. This can become a key tool in identifying cases of culture evolution that are best approached probabilistically, in contrast to those where predictability, equilibrium and ‘optimality’ have traditionally been expected.

Bentley, R.A., P. Garnett, M.J. O'Brien & W.A Brock (2012).
Word diffusion and climate science. . PLoS ONE. Vol 7(11): e47966.
Bentley, R.A. and M.J. O’Brien (2011).
The selectivity of social learning and the tempo of cultural evolution. Journal of Evolutionary Psychology. Vol 9:125-141.
Bentley, R.A., P Ormerod & M. Batty (2011).
Evolving social influence in large populations. Behavioral Ecology and Sociobiology. Vol 65:537-546.
Bentley, R.A., and P. Ormerod (2010).
Agents, intelligence, and social atoms. . In: M. Collard & E. Slingerland (eds) (ed\s) Creating Consilience: Science and the Humanities. OUP.
Bentley, R.A., and P. Ormerod (2010).
A rapid method for assessing social versus independent interest in health issues: A case study of ‘bird flu’ and ‘swine flu’. Social Science and Medicine. Vol 71:482-485.
Byers, B.E., K.L. Belinsky and R.A. Bentley (2010).
Independent cultural evolution of two song traditions in the chestnut-sided warbler. American Naturalist. Vol 176:476-89.
Bentley, R.A. and P. Ormerod (2009).
Tradition and fashion in consumer choice: bagging the Scottish Munros. Scottish Journal of Political Economy. Vol 56:371-381.
Bentley, R.A., M. Madsen and P. Ormerod (2009).
Physical space and long-tail markets. Physica A. Vol 388:691–696.
Bentley, R.A (2009).
Fashion versus reason in the creative industries. . In: M.J. O'Brien & S.J. Shennan (eds) (ed\s) Innovation in Cultural Systems. MIT Press. 121-126.
Earls, M. and R.A. Bentley (2009).
How ideas spread. Research World. Vol April:13-17.
Dr Alex Bentley and Dr Ruth Mace (2008).
Use buzzwords to be cited, study suggests, by Fearn, Hannah . Times Higher Education.
Bentley, R.A.& H.D.G. Maschner (2008).
Complexity theory. In: R.A. Bentley, H.D.G. Maschner & C. Chippindale (eds.) (ed\s) Handbook of Archaeological Theories. Altamira Press : Lanham. 245-272.
Bentley, R.A., M. Earls (2008).
Forget influentials, herd-like copying is how brands spread. Admap magazine. Vol November:19-22.
Bentley, R.A., P. Ormerod, M.E. Madsen (2008).
Physical space and long-tail markets. Physica A. Vol 388:691–696.
Bentley, R.A (2008).
Random drift versus selection in academic vocabulary. PLoS ONE. Vol 3(8):e3057.
Shennan, S.J. and R.A. Bentley (2008).
Style, interaction and demography among the earliest farmers of Central Europe. In: M. J. O'Brien (ed.) (ed\s) Cultural Transmission and Archaeology: Issues and Case-Studies. Society for American Archaeology: Washington, DC.
Tehrani, J., R.A. Bentley, M.J. O’Brien (2008).
Language is nothing special. (Comment). PLoS Biology. Vol 6:e186.
Hill, R.A., R.A. Bentley & R.I.M. Dunbar (2008).
Network scaling reveals consistent pattern in hierarchical animal societies. Proceedings of the Royal Society Biology Letters. Vol 4:748-751.
Bentley, R.A., C.P. Lipo, H. Herzog and M.W. Hahn (2007).
Regular rates of popular culture change reflect random copying. Evolution and Human Behavior. Vol 28:151-158.
Bentley, R.A (2007).
Fashion versus reason – then and now. Antiquity. Vol 81:1071-1073.
Bentley, R.A (2007).
Why do team-authored papers get cited more? (Comment). Science. Vol 317:1496.
Bentley, R.A (2007).
Social complexity in behavioral models. Behavioral and Brain Sciences. Vol 30:19.
Prof Bruce Byers and Dr Alex Bentley (2006).
That birdsong Is so five minutes ago. ScienceNOW.
Dr. Alex Bentley. In conection with project C003: (2006).
Order and Chaos. SETI Institute Science Radio.
Dr. Alex Bentley. In connection with project C003 (2006).
Fashion is fickle, but change constant. The Times.
Dr. Alex Bentley. In connection with project C003: (2006).
Why we're slaves to the latest fashion fads. MSNBC.
Dr. Alex Bentley (2006).
Cultural evolution. BBC Radio 4: Leading Edge.
Bentley, R.A. (2006).
Academic copying, archaeology and the English language. Antiquity. Vol 80:196-201.
Bentley, R.A. and S.J. Shennan (2005).
Random copying and cultural evolution (Comment). Science. Vol 309:877-879.