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EUI Interdisciplinary Experimental Working Group (ECO/SPS)

Dates:
  • Wed 27 May 2020 11.00 - 12.30
  Add to Calendar 2020-05-27 11:00 2020-05-27 12:30 Europe/Paris EUI Interdisciplinary Experimental Working Group (ECO/SPS)

Social Influence Undermines the Wisdom of the Crowd in Sequential Decision-Making

Arnout van de Rijt I Department of Political and Social Sciences

Abstract: 

Teams, juries, electorates, and committees must often select from various alternative courses of action what they judge to be the best option. The phenomenon that the central tendency of many independent estimates is often quite accurate – the wisdom of the crowd – suggests that group decisions based on plurality voting can be surprisingly wise. We argue that the wisdom of the crowd is undermined if group members, as is common in many real-world settings, cast their votes sequentially after first observing the prior votes of others. This happens because in such scenarios early mistakes can cascade across strings of decision-makers. Results from a laboratory experiment confirm that when subjects sequentially state which of two answers they deem correct, majorities are more often wrong when subjects can see how often the two answers have been chosen by previous subjects than when they cannot. As predicted by our theoretical model, this happens even though subjects’ use of social information improves the accuracy of their individual votes. A second experiment conducted over the Internet involving larger groups indicates that while early mistakes on easy tasks are eventually corrected in long enough choice sequences, for difficult tasks wrong majorities perpetuate themselves, showing no tendency to self-correct.

*Authors: Vincenz Frey, Arnout van de Rijt

 

Discrimination in Remembering People: Field and Lab Evidence

Michèle Belot I Department of Economics

Abstract:

Remembering people is at the core of many social and economic relationships. In this paper, we present evidence from two experiments showing systematic biases in the way we remember people according to their gender and race. The first experiment provides evidence on memory in a real professional setting (academia). Conference participants were asked to recall who presented what a month after attending the conferences. The second experiment is a controlled computer-based version of the field: participants are shown pictures of people (drawn from a picture database), matched with the title of a paper. We exogenously vary the relative shares of women and non-white individuals. We observe discrimination in memory: We find that minority attributes (such as being female or non-white) make it more likely to be recalled, but individuals from these groups are also more likely to be confused with each other when confusion is possible. Our findings are in line with the theory of broad categorisation proposed by Fryer and Jackson (2008), where people with whom we interact with less often (the minority groups) are sorted into broad categories, corresponding to their minority attributes We conjecture that these biases could have important implications for the formation of professional networks.

*Authors: Michèle Belot and Marina Schröder  

ZOOM link will be sent after registration.

Registration deadline: 26 May

Online - .. DD/MM/YYYY
  Online - ..

Social Influence Undermines the Wisdom of the Crowd in Sequential Decision-Making

Arnout van de Rijt I Department of Political and Social Sciences

Abstract: 

Teams, juries, electorates, and committees must often select from various alternative courses of action what they judge to be the best option. The phenomenon that the central tendency of many independent estimates is often quite accurate – the wisdom of the crowd – suggests that group decisions based on plurality voting can be surprisingly wise. We argue that the wisdom of the crowd is undermined if group members, as is common in many real-world settings, cast their votes sequentially after first observing the prior votes of others. This happens because in such scenarios early mistakes can cascade across strings of decision-makers. Results from a laboratory experiment confirm that when subjects sequentially state which of two answers they deem correct, majorities are more often wrong when subjects can see how often the two answers have been chosen by previous subjects than when they cannot. As predicted by our theoretical model, this happens even though subjects’ use of social information improves the accuracy of their individual votes. A second experiment conducted over the Internet involving larger groups indicates that while early mistakes on easy tasks are eventually corrected in long enough choice sequences, for difficult tasks wrong majorities perpetuate themselves, showing no tendency to self-correct.

*Authors: Vincenz Frey, Arnout van de Rijt

 

Discrimination in Remembering People: Field and Lab Evidence

Michèle Belot I Department of Economics

Abstract:

Remembering people is at the core of many social and economic relationships. In this paper, we present evidence from two experiments showing systematic biases in the way we remember people according to their gender and race. The first experiment provides evidence on memory in a real professional setting (academia). Conference participants were asked to recall who presented what a month after attending the conferences. The second experiment is a controlled computer-based version of the field: participants are shown pictures of people (drawn from a picture database), matched with the title of a paper. We exogenously vary the relative shares of women and non-white individuals. We observe discrimination in memory: We find that minority attributes (such as being female or non-white) make it more likely to be recalled, but individuals from these groups are also more likely to be confused with each other when confusion is possible. Our findings are in line with the theory of broad categorisation proposed by Fryer and Jackson (2008), where people with whom we interact with less often (the minority groups) are sorted into broad categories, corresponding to their minority attributes We conjecture that these biases could have important implications for the formation of professional networks.

*Authors: Michèle Belot and Marina Schröder  

ZOOM link will be sent after registration.

Registration deadline: 26 May


Location:
Online - ..

Affiliation:
Department of Economics
Department of Political and Social Sciences

Type:
Working group

Contact:
Claudia Fanti - Send a mail

Organiser:
Prof. Klarita Gërxhani (EUI - Department of Political and Social Sciences)
Prof. Michèle Belot ((EUI - Department of Economics))

Speaker:
Prof. Arnout van de Rijt (EUI - Department of Political and Social Sciences)
Prof. Michèle Belot ((EUI - Department of Economics))
 

Page last updated on 18 August 2017