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Resilience Informatics for Innovation Social psychology and group performance

RERC/TMIKazuo FURUTA

Social aspects of decision-making

Social (Collective) decision-makingn decision-making by a group as consensusn Actual style of most decision-makingsn Important for organizational operations

Social influence on individual actionsn Significant for individual decisionsn Significant for organizational operations

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Group processes

Individual Factors(member ability, personality,biographical features, etc.)

Individual Factors(member ability, personality,biographical features, etc.)

Group Factors(group size, structure, group

cohesiveness, etc.)

Group Factors(group size, structure, group

cohesiveness, etc.)

Environmental Factors(task demands, role system,available information, etc.)

Environmental Factors(task demands, role system,available information, etc.)

Group ProcessGroup Process

Social Influence

Individual Performance

Social Decision Scheme

Group PerformanceGroup Performance

Social influence

Taxonomy by Deutsch & Gerald (1955)

Informational influencen An influence to accept information

obtained from another as evidence about reality

Normative influencen An influence to conform with the positive

expectations of another

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Social psychology and group performance

Group characteristicsn Conformity, authority gradient, social loafing,

social facilitation, risky shift, group polarization, groupthink

Leadership theoryn Two functions, PM theory, contingency theory

Communication network

Steiner’s group productivity theory

Group reliability

Conformity pressure

Asch experiment (1951)n One subject and seven confederatesn Line segment selection (obvious correct answer)n Common wrong answer by confederatesn 37% of subjects conformed to wrong answers

Even though the correct answer is apparent, the conformity pressure from a group to an individual is enormous.

Which one is of the same length?

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Authority gradient

Milgram experiment (1963)n The participants were asked to impose electric

shock to the answers (confederates) if they made mistakes in answering questions.

n The experiment was finished when the participants refused to raise the voltage.

n No less than 65% of participants raised the voltage to the upper limit.

Many people obey the authority, though they know they must refuse an order.

Social loafing

Ringelmann effectn ２, ３, ８ people pulled a rope and they showed an

effort of 93%, 85%, 49% of an individual.Latanet experiment (1979)n Participants were asked to make a loud voice in a

sound proof chamber. As participants increased, the loudness of an individual decreased.

Decrease of individual efforts under the participation of othersn Diffusion responsibilityn Murder of Kitty Genovese, Toyota Corp.

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Social facilitation an depression

Social facilitationn Racehorses run faster with others than individuallyn Increase of performance in the presence of others

Social suppressionn Decrease of performance in the presence of others

Zajonc experiment (1965)n Recall of meaningless sequence of words under

different training levelsn Facilitation in highly trained casesn Suppression in poorly trained cases

Risky shift

Kogan & Wallach experiment (1964)n Choice of an action for 12 imaginary situations

from high-risk / high-return or low-risk / low-return options

n Individual choice → group discussion → individual choice

n Group discussion facilitates preference of high-risk / high-return option.

n Why does risky shift occur?w Diffusion of responsibilityw Leadership (Aggressive opinions are likely to dominate)w Group wisdom (Anxiety is suppressed with many eyes)

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Group polarization

Group discussion sometimes enhances a risk averse conclusion.

Group discussion is likely to result in an extreme conclusion in general.

Group polarization seems a specific case of the amplifying effect of collective decision-making explained later.

Groupthinking

A highly qualified and cohesive group sometimes makes a serious decision failure.Janis (1971)n Analyses of historical fiascoes such as the Bay of

Pigs invasion by Kennedy administration

Symptomsn Overestimations of the group: power and moralityn Closed-mindedness: rationalizing warnings and

stereotyping opponentsn Pressure toward uniformity: self-censorship,

illusion of unanimity, direct pressure, mind-guards

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How to prevent groupthink

Silent leader at the beginningAssignment of “Devil’s advocate”Atmosphere that is easy to challengeConsideration of effective alternativesParallel discussion by independent subgroupsInvitation of outside opinions

Leadership style

What is leadership?n Functions and actions of facilitating a group of

people to act towards achieving a common goal

Taxonomy by Cartwright & Zander (1960)n Achievement of goals (Task-oriented, P-function)

n Maintenance of group (Relations-oriented, M-function)

PM theory (1966)n Motivated group PM > M > P > pmn Unmotivated group P > PM > M > pm

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Fiedler’s contingency modelLPC score: high LPC score ⇒ relations-oriented

low LPC score ⇒ task-oriented

1 2 3 4 5 6 7 8Leader-member G G G G P P P PTask structure H H L L H H L LPosition power S W S W S W S W

Corr

elat

ion

betw

een

prod

uctiv

ity a

nd

LPC

scor

e

0

+

−

Steiner‘s group productivity theory (1)

Task demandsn Requirements imposed on the individual or group

by the task (Relevant resources, information, procedure, etc.)

Resourcesn Knowledge, abilities, skills, or tools possessed by

the individuals attempting to perform a task

Group processesn Intrapersonal and interpersonal actions by which

people transform resources into a product

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Steiner’s group productivity theory (2)

[Actual productivity] =[Potential productivity] −[Losses due to faulty processes]

[Potential productivity] = f (Task demands, resources)

Steiner’s typology of tasks

Unitary taskn Disjunctive taskn Conjunctive taskn Additive taskn Discretionary task

Divisible (Complementary) task

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Task type and productivity (1)

Disjunctive taskn If at least one member can successfully complete

the task, the group can also complete it. Pg = 1 - (1 - P)N (Eureka type)

Conjunctive taskn Only if every member can successfully complete

the task, the group can also complete it. Pg = PN

Task type and productivity (2)

Additive taskn The group product is a summative

combination of the outputs of all members.

Discretionary taskn The group can chose an arbitrary scheme

of aggregating its product as a weighted combination of members’ outputs.

∑= iig RwR

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Task type and productivity (3)

Divisible taskn The group can decompose the task into

subtasks, each of which can be performed by a different individual.

n Achievement of the task requires achievement of all subtasks (conjunctive).w Fixed decomposition, fixed allocation.w Fixed decomposition, free allocation.w Free decomposition, free allocation.

Leavitt experiment (1951)

Groups of five people solved simple puzzles by passing hand-written memos.

chain circle

Y wheel

white red

brown

yellow

blue

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Communication network

Centralized networks are advantageous for solving simple problems (Leavitt)n Time required for solutionn Number of messages exchangedn Number of errors

Decentralized networks are advantageous for solving complex problems (Shaw & Mulder)

Group reliability analysis

For assessing general features of group performance, but not for evaluating human error probability of a particular scenario.n Probabilistic modeling of group processesn Group as an information processing network

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Model of group process

hj

i

wijwji

wiσi

Information worthSucc

ess

prob

abilit

y

1

0

)](exp[11

iki

ki

iiij

kjij

ki

p

wSw

βφ

σφ

+−+=

+= ∑≠

=success1

fail0kiS

State transition matrix

If state k and l are neighboring in terms of Si

Otherwise

)](exp[1 iki

ki

ikl S

Gβφ

λ++

=

∑ ∑= ≠=

−=

≠=N

i

N

klklikk

kl

GG

lkG

1 )(1

)(0

λ

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Group dynamics

Kolmogorov’s forward equation

Probability of group success

∑=

−=M

klklk

l tGtdt

td1

)()()( λπππ

schemedecision Social:

)()()(1

s

M

llsls

T

ttTtP ∑=

= π

Symmetric group

Consensus function

Asymptotic probability of group success

++= ∑∑

< i

kiiii

ji

kj

kiijk SwSSwC )(2

1 βσ

∑=

∞→

=Θ

Θ=

M

kk

kkt

C

Ct

1)exp(

)exp(1)(limπ

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Effect of cohesiveness

0.0 1.0 2.0 3.0Group cohesiveness

1.0

0.9

0.8

0.7Pro

babi

lity

of s

ucce

ss

β4 = –5

β4 = 2

β4 = –2

β4 = –4

β4 = –3

Leadership style

0.0 1.0 2.0Group cohesiveness

1.0

0.9

Pro

babi

lity

of s

ucce

ss

Standard leaderTop-downBottom-up

Competent leaderTop-downBottom-up

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Response to emergency

0 50 100Times of decision

0.990

0.985

0.980

0.975

Pro

babi

lity

of s

ucce

ss

w = 1.0

0.995

w = 1.5

w = 2.0