Nav: Home

Researchers determine how groups make decisions

September 18, 2015

From Beats headphones' rise to prominence or a political candidate's surge in the polls to how ants and bees select a new nest site, decisions emerging from groups frequently occur without a leader.

Researchers from Carnegie Mellon University have developed a model that explains how groups make collective decisions when no single member of the group has access to all possible information or the ability to make and communicate a final decision. Published in Science Advances, the de-centralized decision-making model shows how positive feedback during the exploration process proves useful for making good and quick decisions.

"Throughout the presidential primary process, people are trying to find an ideal candidate in a crowded landscape. The person in the lead - say Donald Trump - gets more media coverage and attention, which could lead to more people thinking about voting for him based on name recognition," said David Hagmann, a Ph.D. student in CMU's Department of Social and Decision Sciences. "Eventually, the added exposure could highlight information that people do not like, causing a candidate to fade in the polls."

Hagmann, along with Russell Golman and John H. Miller, developed the mathematical model based on two elements: recruitment with positive feedback, where initially popular options get reinforced, and quorum sensing, where enough support for a given choice triggers a final decision. Using a Polya urn scheme - a statistical model in which balls of different colors are repeatedly drawn from a container and previously picked colors become more likely to be drawn again - the researchers were able to look at how long it takes to make decisions and calculate their accuracy.

"We found that the model is pretty robust across how it is implemented," said Golman, assistant professor of social and decision sciences. "Most interesting, when one choice has more variation in how it is perceived, it's chosen less frequently, establishing systemic risk aversion."

Being a bit risk-averse when deciding on, say, where to relocate thousands of bees, is the evolutionarily safe choice.

"When everyone has to do the same thing, you want to be slow and steady to avoid extreme choices," Golman said.

The process could also be used to explain how the brain's neurons work.

"The way the brain works, you need to get a certain amount of neurons to be active in order to make a decision. Current theories on neuronal decision-making don't take the process of positive feedback into account. But, neuroscience generally recognizes that neurons are connected in recurrent networks, which allow for positive feedback," Golman said.

The model also helps explain how trends take off, such as the popularity of Beats headphones, and the success of word-of-mouth marketing tactics.

"Early adopters are walking advertisements for the products they buy. Choosing the most popular headphones is not necessarily the best option," Golman said, "but it's not a bad rule of thumb."
-end-


Carnegie Mellon University

Related Neurons Articles:

How do we get so many different types of neurons in our brain?
SMU (Southern Methodist University) researchers have discovered another layer of complexity in gene expression, which could help explain how we're able to have so many billions of neurons in our brain.
These neurons affect how much you do, or don't, want to eat
University of Arizona researchers have identified a network of neurons that coordinate with other brain regions to influence eating behaviors.
Mood neurons mature during adolescence
Researchers have discovered a mysterious group of neurons in the amygdala -- a key center for emotional processing in the brain -- that stay in an immature, prenatal developmental state throughout childhood.
Astrocytes protect neurons from toxic buildup
Neurons off-load toxic by-products to astrocytes, which process and recycle them.
Connecting neurons in the brain
Leuven researchers uncover new mechanisms of brain development that determine when, where and how strongly distinct brain cells interconnect.
More Neurons News and Neurons Current Events

Best Science Podcasts 2019

We have hand picked the best science podcasts for 2019. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

Erasing The Stigma
Many of us either cope with mental illness or know someone who does. But we still have a hard time talking about it. This hour, TED speakers explore ways to push past — and even erase — the stigma. Guests include musician and comedian Jordan Raskopoulos, neuroscientist and psychiatrist Thomas Insel, psychiatrist Dixon Chibanda, anxiety and depression researcher Olivia Remes, and entrepreneur Sangu Delle.
Now Playing: Science for the People

#537 Science Journalism, Hold the Hype
Everyone's seen a piece of science getting over-exaggerated in the media. Most people would be quick to blame journalists and big media for getting in wrong. In many cases, you'd be right. But there's other sources of hype in science journalism. and one of them can be found in the humble, and little-known press release. We're talking with Chris Chambers about doing science about science journalism, and where the hype creeps in. Related links: The association between exaggeration in health related science news and academic press releases: retrospective observational study Claims of causality in health news: a randomised trial This...