Ideas worth spreading

How can groups make good decisions?

1,687,599 views |

Mariano Sigman and Dan Ariely |

TED Studio

• April 2017

We all know that when we make decisions in groups, they don't always go right -- and sometimes they go very wrong. How can groups make good decisions? With his colleague Dan Ariely, neuroscientist Mariano Sigman has been inquiring into how we interact to reach decisions by performing experiments with live crowds around the world. In this fun, fact-filled explainer, he shares some intriguing results -- as well as some implications for how it might impact our political system. In a time when people seem to be more polarized than ever, Sigman says, better understanding how groups interact and reach conclusions might spark interesting new ways to construct a healthier democracy.

We all know that when we make decisions in groups, they don't always go right -- and sometimes they go very wrong. How can groups make good decisions? With his colleague Dan Ariely, neuroscientist Mariano Sigman has been inquiring into how we interact to reach decisions by performing experiments with live crowds around the world. In this fun, fact-filled explainer, he shares some intriguing results -- as well as some implications for how it might impact our political system. In a time when people seem to be more polarized than ever, Sigman says, better understanding how groups interact and reach conclusions might spark interesting new ways to construct a healthier democracy.

About the speakers

Dan Ariely

Behavioral economist

See speaker profile

Dan Ariely questions the forces that influence human behavior and the irrational ways we often behave.

Mariano Sigman

See speaker profile

In his provocative, mind-bending book "The Secret Life of the Mind," neuroscientist Mariano Sigman reveals his life’s work exploring the inner workings of the human brain.

Mariano Sigman | William Collins, 2017 | Book

The Secret Life of the Mind

James Fishkin | Yale University Press, 1993 | Book

Democracy and Deliberation: New Directions for Democratic Reform

This book proposes a new kind of democracy for the modern era, one that not only gives citizens more power but also allows them more opportunities to exercise this power thoughtfully. James S. Fishkin here suggests an innovative solution to the problem of inadequate deliberation, in particular within our presidential nomination system. His reform involves a well-publicized national caucus in which a representative sample of American citizens would interact directly with presidential contenders in order to reflect and vote on the issues and candidates.

Isaac Asimov | Ace, 1990 | Book

Robot Dreams (Remembering Tomorrow)

This book is recommended especially for the short story “Franchise” in which Asimov inquiries about our capacity to to sample a small number of votes to predict a total election outcome, and takes this idea to the extreme, reflecting on voting and deliberation.

Charles Macka | Dover Publications, 2003 | Book

Extraordinary Popular Delusions and The Madness of Crowds

A classic that still reflects the most relevant principles on why collective decisions may go wrong, and lead to misconception, and delusion. Written more than 150 years ago it seems that it is never been as relevant as in these days.

Joaquin Navajas, Tamara Niella, Gerry Garbulsky, Bahador Bahrami and Mariano Sigman | Article

"Aggregated knowledge from a small number of debates outperforms the wisdom of large crowds"

Aggregated knowledge from a small number of debates outperforms the wisdom of large crowds. This preprint (accepted in principle in the journal Nature Human Behavior) presents the experiment described in the first part of the talk, providing experimental demonstrations that small debates lead to much more accurate collective judgments.

Jan Lorenza, Heiko Rauhutb, Frank Schweitzera and Dirk Helbing | PNAS, 2010 | Article

"How social influence can undermine the wisdom of crowd effect"

This paper shows how (and why) social influence can undermine the wisdom of the crowds.

Gabriel Madirolas and Gonzalo G. de Polavieja | PLOS, 2015 | Article

"Improving Collective Estimations Using Resistance to Social Influence"

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TEDxperiments at TEDxRíodelaPlata 2016

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TEDxperiments at TEDxRíodelaPlata 2015

The TEDxRíodelaPlata event where we performed this experiment to ask how debates may improve collective wisdom.

View another TEDxperiment from 2015 here.

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TEDxperiments at TEDxRíodelaPlata 2014

This talk is part of the TEDxperiments project, in which we seek at TED to create new ideas in stage experiments. It asks why we often do not cooperate when it is optimal to do so.

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TEDxperiments at TEDxRíodelaPlata 2013

This talk is part of the TEDxperiments project, in which we seek at TED to create new ideas in stage experiments. It deals with the impact of distraction and inattention on human communication.

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