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Symbolic information causes biased decisions

Thursday 1 June 2017, 13.30-14.30
Baines Wing SR (4.12), University of Leeds
Prof Michael Siegrist (Institute for Environmental Decsions, Zurich)


“In assessing the outcomes of decisions, people often rely on the symbolic information while neglecting other crucial information. People may be especially prone to rely on this information on topics that are subject to social norms, such as environmentally friendly behaviour, environmental risks or risks for humans.

In one experiment, participants were presented with two energy consumer descriptions. One contained a positive symbolic significant attribute (e.g., driving a Toyota Prius) and a negative symbolic neutral attribute (e.g., covering 28,700 km); for the other one, the reverse was true (e.g., driving an SUV and covering 11,400 km). As expected, participants were influenced by the symbolic information and this resulted in biased decisions.

In another set of experiments, we could show that negative outcomes are more negatively perceived if caused by humans compared with nature. Perceiving gene technology as unnatural may be one reason why the risks and the benefits associated with this technology is perceived differently compared with the risks and the benefits associated with conventional breeding technology.

The results of our experiments demonstrate that symbolic information may cause biased decisions. These biased decisions have been observed in different contexts, and they may result in non-optimal decisions.”


Michael Siegrist is a Professor for Consumer Behaviour at the Institute for Environmental Decisions (IED), ETH Zurich, Switzerland.

He studied psychology, economics and mass communication at the University of Zurich. He worked as a research assistant at the Psychology Department of the University of Zurich. In 1994 he wrote his dissertation at the University of Zurich. During 1997-1998 he worked as a Project Manager at the Swiss Association of Milk Producers, Department of Marketing Research. During 1998-2000 he was a visiting researcher at Western Washington University, WA, USA (funded by the Swiss National Science Foundation). He returned back to the University of Zurich, and worked as a senior researcher. In 2001 he completed his ‘Habilitation’ at the Faculty of Arts at the University of Zurich.

Professor Siegrist has published numerous articles about risk perception, trust, risk communication and food choice behaviour. His research focuses, at the moment, on acceptance of new technologies, and consumer behaviour in the food domain. He is an Area Editor of the Journal Risk Analysis and an executive editor of Appetite.

This seminar is jointly presented by Centre for Decision Research, Priestley International Centre for Climate, Sustainability Research Institute and ESRC Centre for Climate Change, Economics and Policy