Decision making in groups:strategic behaviour,
biased processing and interpersonal emotions
Claudia Toma Laboratoire de Psychologie Sociale, Grenoble University
Louvain, May the 10th, 2007
Overview of this talk
Research Directions
I. Strategic information sharing and decision quality
3 Studies ( I.1, I.2, & I.3)
II. Biased processing in decision making
3 Studies (II.1, II.2, & II.3)
Possible contributions to ADSR
Decision making in groups
Decision making involves information processing, namely sharing and use of available information that group members possess (Hinsz, Tindale, & Vollrath, 1997).
▪ Hidden profile studies:- groups are less than optimal users of information- group decisions are often suboptimal (Stasser, 1999).
The added value of decision making in groups (McGrath, 1984):
information gains & improved decision quality
Hidden profile paradigm
(Stasser & Titus, 1985, 1987, 2003)
Decision1
(Member 1)
Decision 2
(Member 2)
Decision 3
(Member 3)
Optimal Decision
(Group) PHASE I : individual decisionsPHASE II: group discussion
Sharedinformation
Unsharedinformation 1
Unshared
informatio
n 2
Unsh
ared
information
3
Biased sampling effect
POOLING: Shared Unshared information
REPETITION: Shared > Unshared information
DISCUSSION TIME: Shared > Unshared information
Poor decisionquality
(Stasser & Stewart, 1992; Stewart & Stasser, 1998; Stasser, Stewart, & Wittenbaum, 1995; Hollingshead, 1996; Larson, Christensen, Abbott, & Franz, 1996;Brodbeck, Kerschreiter, Mojzisch, Frey, & Schulz-Hardt, 2002)
Theoretical explanations
BIASED SHARING and PROCESSING Collective sampling bias (Stasser & Titus, 1985, 1987)
Confirmation bias (individual decisions focusing) (Greitemeyer & Schulz-Hardt, 2003 )
SOCIAL VALUE of SHARED INFORMATION Social validation (Wittenbaum, Hubbell, & Zuckerman, 1999)
Toward a “SOCIAL VALUE of UNSHARED
INFORMATION” explanation
The control of information is an important base of
social power (French & Raven, 1959).
Group members should be motivated to strategically use their information in order to get a competitive advantage in group.
Competition is likely to occur in hidden profiles
(Wittenbaum, Hollingshead, & Botero, 2004).
Motivated information sharing and use (Wittenbaum et al., 2004)
Features of Context
Members’Goals
What Information is Mentioned?
How InformationIs Used?
To Whom ?
DecisionQuality
MembersRelations
TASK
AFFECTIVE
OUTPUTS
PROCESSES
INPUTS
Cooperationvs.
Competition
UnsharedShared
HiddenProfile
Discovery
MistrustHarmful
Intentions
Disconfirmationof initial decisions
GoalsInterdependence
+ and -
Hypothesis 1: less information sharing, especially unshared information.
Hypothesis 2: a) lesser use of disconfirmation; b) mediation by expressed initial decisions (dissent).
Hypothesis 3: a) suboptimal decisions;b) mediation by unshared information and
disconfirmation.
I. Strategic information sharing and decision quality: Main Hypotheses
Competition, compared to cooperation, leads to:
ProcedurePHASE I: individual decisions
Member 1
Member 2
Member 3
Decision 1
Decision 2
Decision 3
Dissent
PHASE III: interpersonal emotions measures
PHASE II: group decision
COOPERATION
COMPETITION
GroupDiscussionvideotaped and coded
=
Results on group processes:
information sharing (H1)
F(1,26) = 7.42, p < .05.
Similar results were found for information repetition.
23,21
14,4613,14
10,43
0
5
10
15
20
25
cooperation competition
unshared
shared
Results on group processes:disconfirmation of initial decisions (H2a & H2b):
Cooperation (+1)
Competition (-1) Disconfirmation.70*** (.01 ns)
Initialdecisions(dissent).85*** .82***
zSobel = 3.60
p<.001
.70***
Results on outcome :Decision quality (H3a & H3b)
Cooperation (+1)
Competition (-1)Decisionquality1.74** (1.10 ns)
Unsharedinformation
.60** .23*
zSobel = 2.18
p<.05
Disconfirmation
.70***
1.74** (.69 ns)
1.38*
zSobel = 2.31
p<.05
1.74**
Mistrust, harmful intentions and decision making
Mood influence information processing (Forgas, 1992). And focusing in hypothesis testing (Gangemi & Mancini, 2007).
2 3 4 5 6
1. Decision quality .74*** .69*** -.49** -.44* -.46*
2. Disconfirmation .81*** -.48** -.42* -.44*
3. Unshared info -.55** -.48** -.51**
4. Mistrust 91.*** .84***
5. Self harmful intentions
.78***
6. Others’ harmful intentions
Preliminary Conclusions In competition (compared to cooperation) group members are
strategic when pooling less unshared but not less shared information.
Initial decisions are less mentioned in competition which explain that disconfirmation and unshared information were ineffective, leading to poor decision quality.
Mistrust and harmful intentions are linked to decision quality.
ADDITIONAL QUESTIONS :
Is competition responsible for the biased sampling effect ?
Under which conditions? Study I.3
Ineffective disconfirmation (in competition) might reflect a biased
processing, namely focusing on initial decisions. Study II.1
Study I.3We manipulated task uncertainty with regard to the final decision:
- High uncertainty (four alternatives are equally probable)- Low uncertainty (one alternative is probable)
Reducing uncertainty is a main concern when taking decisions(Raiffa, 1968; Tversky & Kahneman, 1974).
Uncertainty leads to two distinct effects:a) motivates information search (Lanzetta & Driscoll, 1966, 1968);
COOPERATION : unshared > shared information
b) results in higher levels of threat (Conolley, Gerard, & Kline, 1978).
COMPETITION : shared > unshared information
Results on information sharing
18,42
11,67
5,25
10,92
4
9
14
19
24
29
cooperation competition
27,08
11,67
21,25
18,25
4
9
14
19
24
29
cooperation competition
unshared
shared
Low uncertainty High uncertainty
F (1,43) = 4.43, p <.05
Participants’ ratings : more information was needed and more competition was perceived under high uncertainty.
II. Biased processing: Study II.1.
Hypothesis : Less disconfirmation in competition reflects more focusing on initial decisions (confirmation bias).
Incompleteinformation
↓Decision 1
(suboptimal)
Phase I
Manipulation
Coop, Comp
Dissent
Phase II
All informationavailable
↓Final decision
Phase IV
Subsequentinformationevaluation
(consistentinconsistent)
Phase III
We manipulated: Cooperation vs. Competition
Dissent (Yes vs. No)
using an individual task with fictitious group discussion.
Confirmation bias: focusing on initial decisions
χ²Wald (1, N=80) = 3.99, p < .05
4
14
67
0
2
4
6
8
10
12
14
16
cooperation competition
dissent
no dissent
Mediated moderation hypothesis
Information value = consistent information – inconsistent information
CooperationCompetition
ConfirmationInformation
value
Dissent
PREDICTORS
Equation 1
(DV=CB)
Equation 2
(ME)
Equation 3
(DV=CB)
B Wald B t B Wald
IV : COOP, COMP 1.231 6.01* -0.575 -1.25 1.088 3.46
MO: DISSENT .464 0.85 -0.808 -1.76 0.109 0.03
IV X MO 2.005 3.98* -3.017 -3.29*** 1.103 0.89
ME: INFO
VALUE-0.529 9.73**
ME X MO -0.391 1.32
Muller, Judd, & Yzerbyt (2005)
General Conclusions
In decision making tasks involving social threat (competition) and interdependence with others (hidden profile) :
people are strategic when pooling information; this effect is reinforced under high uncertainty;
people are biased when processing subsequent information;
strategic information pooling and biased processing result in poor decision quality;
mistrust and harmful intentions are linked to strategic andbiased processing in decision making.
Possible contributions to ADSR
1)Emotion perception and decision making :others’ emotions as a source of information
Aim: Directly investigating the effect of mistrust and others’ harmful intentions on post-decisional information search andbiased processing.
General Hypothesis: Mistrust and harmful intentions should lead to focus on initial decision and increase in search for consistent information.
2) Emotion perception and decision making :biases in decoding others’ emotions
Aim: Investigating when and why biases occur in decodingemotions (e.g., fear of exploitation) in threatening situationsinvolving social interdependence and how this impacts decisions(e.g., playing cooperatively).
General Hypothesis: Biases in decoding others emotions should occur more likely when there is high similarity between self andothers with impact on decision processes.
3) Empathy and decision making :affective forecasting
Aim: Investigating the role of expectations on affective forecastingand empathetic responses in cooperation and competition andhow this impact behavioral decisions (e.g., information sharing).
General Hypothesis: In competition, compared to cooperation,individuals underestimate others cooperative behavior and therefore they should primarily infer negative emotional state(e.g., distress), manifest counter empathetic responses leadingto information withholding and distortion.
Decision making in groups:strategic behaviour,
biased processing and interpersonal emotions
Claudia Toma Laboratoire de Psychologie Sociale, Grenoble
Louvain, May the 10th, 2007
Task characteristics
Dissent between individual decisions and a disconfirmation strategy leading to an optimal decision; (pilot studies 1- 4)
Known diagnostic value of unshared information and possibilityto identify shared from unshared information; (pilot study 5)
Perceived intragroup interdependence. (pilot study 6)
χ² (1, N=28) = 12.85,
p < .001
Results on outcome:
decision quality (H3a) 13
4
1
10
0
2
4
6
8
10
12
14
cooperation competition
success
failure
Mistrust and jealousy
1,63
3,04
2,24
1,45
0
0,5
1
1,5
2
2,5
3
3,5
Mistrust Jealousy
cooperation
competition
t(26)= 4.48p < .001
t(26)= 1.70p = .10