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Biased Information Searchin Group Decision Making

By Schulz-Hardt, Stefan, Dieter, Carsten, Serge

July, 2004

Helayne Sweet

Biased Information Search in Group Decision Making, 2

Background and Importance of Question Addressed

Question is -> How do biased information-seeking processes occur within groups and to what extent?

— Article presented 3 experiments to demonstrate extent to which biased information searches appear in decision making.

— What is biased information-seeking or confirmation bias?– Relates to preference for supporting information vs. conflicting

information when making decisions

Importance -> because decisions with “far-reaching implications are most often made by groups vs. individuals.”

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Background/Study Methods

Three experiments to examine confirmation bias and group decision-making

— Experiment 1 ->Looked at groups as sum of individual preferences (assumed strength of bias depended on distribution of group members decision preferences).

— Experiment 2 -> Used “experts”/managers in experiment

— Exoerunebt 3 -> Looked at difference between heterogeneous vs. homogeneous groups

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Biased Information Search in Group Decision Making,

Study Methods (continued)/Results

Three areas of reseach about belief that groups perform more balanced information searching than individuals

— In experiment 1 -> groups were to determine best approach for new curriculum for economic sciences program using case study approach (scenario of industrial company should invest/not invest in another developing country)

– Allowed for selection of articles (5:5 ration of supporting vs. conflicting articles prior to group discussion)

– Examined individual preferences, results-> groups accentuate dominate tendencies (supporting information is a dominant bias)

— In experiment 2 -> used experts instead which lead to better validity of results. Result -> the greater the diversity of the individual preferences in the group, the more reliance on shared information (supporting information). Used same ratio as above

— In experiment 3 -> focused on difference between homogeneous and heterogeneous groups – used different case study - > did not allow for review of articles until after discussion. Also implemented rating approach for how important good decision making was for each member in group, how certain they were about correctness of decision and difficulty of obtaining decision. Also asked how sympathetic they judged each of the other group members.

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Biased Information Search in Group Decision Making,

General Conclusions

Depending on impact of decision, homogeneous groups may be appropriate (even though they show premature convergence and defective information searching capabilities).

Advantage of heterogeneous group using group processes implies occurrence of bias in early stages of decision process more preventable.

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Discussion

Case Study: Assume you have opportunity to form decision making group for purposes of deciding how many life preservers you should have on the Titanic. What type of group would you form?

What type of group decision-making do you think was made in real situation? Why?