Introduction to Social Psychology

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Introduction to Social Psychology

• Lecture 8
• Group Performance

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Theme for today is the whole different from the
sum of the parts?

• Human beings (and social psychologists) have long
  pondered the relation between individual and
  group e.g. too many cooks spoil the broth,
  many hands make light work.
• Important applied implications organisation of
  work, decision making.
• This lecture (a) group decision making (b)
  group productivity.

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Some hypotheses on the relation between
individual and group decisions

• Averaging or compromise the group converges on
  the median position of the group members
• Conservativism group inertia means that they
  are inherently more cautious than the individuals
  that comprise them
• Or,? the risky shift paradigm

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Wallach, Kogan Bems (1962) classic study J
Abnormal Social Psychology, 65, 75-86

• 12 social dilemmas answered by individuals
• Same dilemmas resolved to consensus by groups
  made up of same individuals
• Compare average of each N individuals prior to
  discussion to group consensus opinions
• Sample items
• G, a competent chess player, is participating in
  a national chess tournament. In an early match
  she draws the top-favoured seed as her opponent.
  During her game with this person G notes the
  possibility of a deceptive though risky play
  which might bring her victory. However, if the
  move failed, defeat would almost certainly
  follow.
• J and her boyfriend have been planning to get
  married. However, some recent arguments between
  them suggest some sharp differences of opinion
  over some important issues and, although still
  keen to marry, is now less sure. Discussions with
  friends indicate that a happy marriage, whilst
  possible, would not be by any means certain.
• On each item, participants have to indicate the
  lowest probability of success that they would
  accept before advising the protagonist to
  undertake the action in question in odds out of
  10 from 1/10 to never do it, no matter what the
  odds

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Are group decisions riskier than individual
decisions.?Wallach, Kogan Bem (1962)
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..or simply more extreme?data from British
students over 8 years practical classes see
also Fraser, Gouge Billig (1971) Eur. J. Soc.
Psych., 1, 7-30
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Explanations for group polarization

• Social comparison hearing others opinions in
  the group highlights the socially valued position
  on each item and also indicates that you may not
  be as close to that socially desirable view as
  you thought. Hence, you gravitate, not to the
  group mean but to the perceived desirable view.

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Evidence for social comparison viewTeger
Pruitt (1967) J. Exp. Soc. P., 3, 189-205
Correln between initial -.20 .70
.80 posn and degree of shift
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Explanations for group polarization

• Social comparison hearing others opinions in
  the group highlights the socially valued position
  on each item and also indicates that you may not
  be as close to that socially desirable view as
  you thought. Hence, you gravitate, not to the
  group mean but to the perceived desirable view.
• Persuasive arguments hearing others opinions,
  which will tend to be more on one side of an
  issue than the other, persuades you that you
  were right all along, and even more right than
  you first thought. So you shift in that initially
  preferred direction.

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Evidence for persuasive argumentsEbbeson
Bowers (1974) J. Personality Soc. P., 29,
316-327
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Group productivity

• Historically one of the earliest areas of
  research (1897 onwards).
• Early work suggested that presence of others
  seemed to make people work harder
• Later work indicated that this was too simple a
  view on many tasks the group seemed to be less
  than the sum of its parts

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Problem solvingTaylor Faust (1952) J. Exp.
P., 44, 360-363

• Speed (mean time to soln, in mins)
• 4 persons 2 persons Individual
• 3.15 3.70 5.06
• Efficiency (i.e. person-minutes)
• 12.60 7.40 5.06

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BrainstormingTaylor , Berry Block (1952)
Admin. Sci. Q., 3, 23-47

• Mean number of original ideas
• Average individual 19.6
• Interacting groups (of 4) 37.5
• Combining ideas from 4 individuals 68.1

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Individual and collective memoryStephenson et
al. (1986) J Personality Social P., 50,
1113-1122

• Number of items correctly recalled (max 18)
• Groups (of 4) Groups (of 2) Individuals
• 13.7 10.9 8.2
• Confidence in their answers, right or wrong (1-4)
• 3.4 2.9 2.6

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Steiners theory of group productivity

• For any task there is some theoretical maximum
  potential productivity
• Actual productivity always falls short of this
  due to losses incurred in the group process Pa
  Pp losses
• Calculating Pp depends on task e.g. tug-of-war
  (Ringelmann, 1913) is an additive task, therefore
  Pp is sum of individual efforts Avge individual
  80Kg, therefore Pp of an 6 person group is
  480Kg Pa was actually 320Kg, a loss of 160Kg.

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Social loafing in rope-pulling taskIngham et
al. (1974) J. Exp. Social Psych., 10, 371-384
Motivation losses
Coordination losses
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Overview   Theme for lecture is the whole
different from the sum of its parts?   1. Group
decision making   Groups typically make more
extreme decisions than the average of their
individual members positions, e.g. Wallach et
al. (1962), Fraser et al. (1971).   Two
explanations for this   (a)    Social comparison
processes, e.g. Teger Pruitt (1967) (b)  
Persuasive arguments, e.g. Ebbeson Bowers
(1974)     2. Group productivity   (a)    Several
studies show that groups can outperform
individuals, but at some cost in terms of
efficiency. E.g. problem-solving (Taylor
Faust, 1952) brainstorming (Taylor et al., 1958
memory, Stephenson et al., 1986). (b)   Steiners
theory of group productivity. Actual productivity
Potential productivity losses due to group
process   E.g. Rope pulling task Ringelmann
(1913), Ingham et al. (1974).  
Further reading   Hogg. M Vaughan, G. (2002)
Social Psychology, 3rd Edition, chs 8-9 Brown,
Roger (1986) Social Psychology, 2nd Edition, ch
6 Brown, R. (2000) Group Processes, 2nd edition ,
ch 5.