Free riders and altruists:
the effect of individual decisions on group-level cooperation
Andrea Czibor, Tünde Paál, Tamas Bereczkei Institute of Psychology, University of Pécs, Hungary
www.evolutionpsychology.com
Individuals may have been selected for decision making mechanisms that can help to choose the optimal behavioral strategies in social dilemma situations (SDS).
While former studies have revealed the typical behavioral patterns and strategies in SDSs, they paid relatively little attention to the underlying personality traits and the constraining situational factors.
Introduction
Aim of the study
Results
Conclusions Subjects
150 undergraduate students from the University of Pécs (69 men, 81 women)
Mean age: 22,2 (Std. dev.: 2,35) Experimental games
Participants made decisions in two social dilemma situations, in cooperative and competitive versions of the Public Goods Game (PGG).
Free riders and altruists
Individuals whose contribution to the public good was under 20%
of the available maximum were labeled „free riders”, while
individuals who transferred more than 80% of their money to the public account were labeled as „altruists”.
Variables measured
1. Personality factors of free riders and altruists;
a) Temperament and character factors (TCI by Cloninger, 1987)
• Novelty Seeking (NS)
• Harm Avoidance (HA)
• Reward Dependence (RD)
• Persistence (P)
• Self-Directedness (SD)
• Cooperativeness (C)
• Self-Transcendence (SD)
b) Machiavellianism(Mach IV by Christie & Geis, 1970) 2. Their contributions and payoffs;
3. The effect of their presence on group-level cooperation were analyzed.
Materials and methods
The present study is aimed at exploring the effects of the presence of non-cooperative (free rider) and extremely cooperative (altruist) group members on the contributions and payoffs of the other group members.
Differences in personality characteristics among free rider and altruist players is also explored.
While the free rider strategy was individually profitable, it decreased group- level cooperative potential.
Altruism was a reliable signal of cooperativeness in the cooperative version of PGG that might induce others to behave in a group-oriented manner.
Personality factors and the proportion of altruist and free rider group
members seemed to be important cues for adaptive decisions in SDS.
Differences in personality traits among individuals who chosed free-rider or altruist strategy in the experimental games (m: p<0,1; *: p<0,05; **:
p<0,01)
The frequency of free rider and altruist strategies in the two experimental setting
Competitive situation
Cooperativ e situation
% %
Free rider 26 24
Altruist 16 38
While the number of free
riders was fairly constant in the two game settings, the number of altruists was context-dependent: this strategy appeared more prevalent in the
cooperative game.
0 20 40 60 80 100
120
Free riders
Altruists
m
0 20 40 60 80 100 120
Free riders Altruists
Cooperative situation Competitive situation
Individual payoffs attained by subjects with different strategies
-400 -300 -200 -100 0 100 200 300
Free rider
Other strategy
Altruist
Profit according to partners (HUF)
Profit in the competitive PGG
-200 -150 -100 -50 0 50 100 150 200 250
Profit according to partners (HUF)
Profit in the cooperative PGG
A typical free rider (high
Machiavellianism, low
Cooperativeness, low Persistence score) was
financially
successful in both settings.
In groups with at least one free rider member, the average
contribution of other members was
significantly lower in both cooperative and competitive settings.
The presence of altruists promoted increase in the
average contributions only in the cooperative setting.
Effects of free rider and altruist group-members on group-level cooperation
Effect of free riders
Effect of altruists
359 295
489
675
0 200 400 600 800
Competition Cooperation
Average contribution (HUF)
At least one free rider member No free rider member
** **
449
679
438 426
0 100 200 300 400 500 600 700 800
Competition Cooperation
Average contribution (HUF)
At least one altruist member No altruist member
**
SROP-4.2.2/B-10/1-2010-0029 Supporting Scientific Training of Talented Youth at the University of Pécs
TÁMOP-4.2.1. B-10/2/KONV-2010-0002
Developing the University Marketableness of the South-Transdanubian Region
