Study: Groups outperform the best individuals at problem solving

By SamuelRose, published at 10 May 2007 - 8:12pm, last updated 10 years 27 weeks ago.

[Thanks Madtom]

A study by Patrick R. Laughlin, Erin C. Hatch, Jonathan S. Silver, and Lee Boh of the University of Illinois at Urbana–Champaign, published in the APA Journal of Personality and Social Psychology, finds that group problem solving is more effective than problem solving by even the best individual expert.

Groups of three, four, or five perform better on complex problem solving than the best of an equivalent number of individuals, says a new study appearing in the April issue of the Journal of Personality and Social Psychology, published by the American Psychological Association (APA). This finding may transfer to scientific research teams and classroom problem solving and offer new ways for students to study and improve academic performance, according to the study authors.

In this study 760 students from the University of Illinois at Urbana- Champaign solved two letters-to-numbers coding problems as individuals or as groups of two, three, four and five people. Previous research has shown that groups perform better than the average individual on a wide range of problems. However, this study tested the relationship between group size and performance as compared to that of an equivalent number of individuals by comparing the number of trials to solutions and answers given for complex problems. The groups of three, four, and five performed better than the best of an equivalent number of individuals on the letters-to-numbers problems.

"We found that groups of size three, four, and five outperformed the best individuals and attribute this performance to the ability of people to work together to generate and adopt correct responses, reject erroneous responses, and effectively process information," said lead author Patrick Laughlin, PhD., of the University of Illinois at Urbana-Champaign.

Moreover, groups of two performed at the same level as the best of two individuals, suggesting that this group size was too small to introduce the necessary dynamics for optimal problem-solving. However, since groups of three, four, and five were able to achieve the same results, the authors submit that groups of at least three are necessary and sufficient to perform better than the best of an equivalent number of individuals on complex problems that require understanding of verbal, quantitative, or logical conceptual systems. Understanding these systems are necessary skills for scientific research teams, and the finding that groups of three or more perform better than the best of the same number of individuals may indicate that scientific research teams perform better than their top member would perform alone.

"Problem solving groups may also be a useful method for students to use in school," said Laughlin. Further research is necessary to determine if cooperative groups perform better than the best individuals in academic settings with different age groups and for other forms of problem solving.

Paper: "Groups Perform Better Than the Best Individuals on Letters-to-Numbers Problems: Effects of Group Size", Patrick Laughlin, Erin Hatch, Jonathan Silver, and Lee Boh, University of Illinois at Urbana Champaign; Journal of Personality and Social Psychology, Vol. 90, No. 4

Groups Perform Better Than the Best Individuals on Letters-to-Numbers
Problems: Effects of Group Size

Patrick R. Laughlin, Erin C. Hatch, Jonathan S. Silver, and Lee Boh
University of Illinois at Urbana–Champaign

Individuals and groups of 2, 3, 4, or 5 people solved 2 letters-to-numbers problems that required participants, on each trial, to identify the coding of 10 letters to 10 numbers by proposing an equation in letters, receiving the answer in letters, proposing a hypothesis, and receiving feedback on the correctness of the hypothesis. Groups of 3, 4, and 5 people proposed more complex equations and had fewer trials
to solution than the best of an equivalent number of individuals. Groups of 3, 4, and 5 people had fewer trials to solution than 2-person groups but did not differ from each other. These results suggest that 3-person groups are necessary and sufficient to perform better than the best individuals on highly intellective problems.

Keywords: group problem solving, group size, intellective tasks

Full Paper available here:
http://www.apa.org/journals/releases/psp904644.pdf
[PDF, 8 Pages, 66kb]