13th international conference on social dilemma
Kyoto, 20-24th August 2009
Reputational advantages and
disadvantages of punishment
toward norm-violators
Yutaka Horita
Toshio Yamagishi
Hokkaido University
Question：
Is costly punishment sustainable?
➔ Yes, but only when punishers get rewarded.
Do punishers get rewarded for their punitive
behavior?
We investigated this question using a scenario
study.
Flash report of the findings
In a prisoner’s dilemma game,
69 % of our participants wanted to
play with a punisher rather than a
non-punisher.
Prisoner’s
dilemma
Punisher’s payoff: 6,346
> Non-punisher’s payoff: 2,500
When a punisher was a
recipient in a dictator game,
Allocator
Only 33% of our participants wanted
to play with a punisher rather than a
Recipient non-punisher.
Dictator game
Punisher’s payoff: 2,964
< Non-punisher’s payoff: 4,655
The answer to the question depends on the type of game.
The details of the study follows…
Background
Punishment of free-riders is a key to maintain
cooperation in n-person dilemmas.
(e.g., Yamagishi, 1986 Fehr & Gächter, 2002)
However, punishment invokes a second-order social
dilemma problem (Yamagishi, 1986).
If punishers get rewarded and the benefits surpass the
cost of the punitive behavior, the punishment of freeriders can be sustained.
However, people do not seem to reward punishers.
(Kiyonari & Barclay, 2008)
Outline of this study
The game type is important.
►Punishers were not rewarded by others when they were
a recipient in a dictator game.
► Punishers may be rewarded when they play a
prisoner’s dilemma game.
In addition to these two games, we examined other
games using scenarios.
►Participants chose either a punisher or a nonpunisher as a game partner in those games.
Method
Participants: 57 undergraduate students (40 males, 17 females)
Participants read an initial scenario describing a public goods game
or a third-party punishment game (Fehr & Fischbacher, 2006).
In each initial scenario, a punitive cooperator and a non-punitive
cooperator were depicted.
Initial scenario
or
Participants
Third-party punishment game
Public goods game
-10,000 yen
-2,000 yen
Punish
※Punishers paid costs to decrease
punisher
non-cooperator’s payoff
※We pooled two initial scenario
conditions when we analyzed.
non-punisher
non-cooperator
non-cooperator
Method: partner choice
After reading the initial scenario (the public goods game or the
third party punishment game), participants read 8 scenarios
and were asked to imagine themselves in the player’s role.
1. Prisoner’s dilemma game (PD)
2. Public goods game (PGG)
3. Proposer
4. Responder
Ultimatum game (UG)
5. Allocator
6. Recipient
Dictator game (DG)
participants
7. Truster
8. Trustee
Trust game (TG)
Method: partner choice
We asked participants whether they would want to choose
either a punisher or a non-punisher as a game partner in each
game.
punisher
non-punisher
Which person do I
want to play this
game with…?
Result: partner choice
Punishers were chosen more
than non-punishers.
Punishers were chosen less
than non-punishers.
Punishers were less chosen as a game partner than non-punishers.
：Participant
：Punisher
Responder
Proposer
Ultimatum game
Group fund
Allocator
Recipient
Dictator game
Public goods game
Trustee
Truster
Trust
game of rewards.
Punishers
were not chosen as a
recipient
This
result
suggests
that punishers
not rewarded
by others.
In
these
games,
punishers
were the are
recipient
of resources.
Punishers were more chosen as a game partner than non-punishers.
：Participant
：Punisher
Prisoner’s dilemma
Allocator
Recipient
Dictator game
Trustee
Trust
PunishersTruster
were chosen
as game
resource providers.
Punishers
were trusted
more
than
were non-punishers.
In these games,
punishers
were
providers
of resources.
Further analysis: Evaluation
Why were punishers chosen as providers?
➔ We analyzed how our participants evaluated punishers and nonpunishers.
Participants rated their general impression of punishers and nonpunishers by comparing the punisher and the non-punisher on 25
impression items.
(7 points scales)
Which person is more “trustworthy”,
“kind”, “friendly” and so on.
3 2
non-punisher
1
0 1
same
2
3
punisher
participants
Further analysis: Evaluation
Principle component analysis revealed 4 dimensions of evaluation.
Friendliness (α=.79): “want to be friends with,” “feel safe with,”
“kind,” “respected by others,” and so on.
Justice-seeking (α=.85) : “worthy leader,” “relied on by others,”
“justice minded,” “socially desirable character,” “trustworthy,” and
so on
Harmony seeking (α=.80) : “concerned about own reputation,”
“likely to get help from others,” “respects group harmony,” and so
on.
Cleverness (α=.68) : “clever,” “get along well in society,” and
“meddling” (reverse)
Result: Evaluation
Non-punisher←　→Punisher
1.80
1.40
1.00
0.60
0.20
-0.20
-0.60
Friendliness
Justiceseeking
Harmonyseeking
Cleverness
-1.00
-1.40
-1.80
Punishers
as chosen
more justice-seeking
non-punishers.
Punisherswere
mayevaluated
have been
as providersthan
because
they
were
perceived
as fairness-seeking.
Punishers
were perceived
as less friendly and harmony-seeking than
non-punishers.
Non-punishers may have been chosen as recipients because they
were
perceived
as friendly
Punishers
were perceived
as and
less agreeable.
socially clever than non-punishers.
Further analysis: Behavior
Are there other benefits to punishers?
Participants stated how they and their partner (the punisher or the
non-punisher) would behave in each game.
We calculated how much punishers and non-punishers would
earn, if they and participants actually behaved the way
participants had stated.
We called these calculated earnings the “expected payoff”.
punisher
non-punisher
interact
Result: Behavior
Games in which a punisher /
non-punisher plays
Punisher
was chosen
(%)
(yen)
Participant’s
expected payoff
from nonpunisher (yen)
Participant’s
expected payoff
from punisher
Dictator in Dictator Game
76.8
9,351
7,527
Prisoner’s dilemma game
69.2
9,385
7,946
Trustee in Trust Game
66.0
9,232
8,386
Proposer in Ultimatum Game
58.2
9,071
8,473
Truster in Trust Game
36.4
8,509
9,679
Recipient in Dictator Game
32.7
11,732
12,123
Public Goods Game
30.9
16,527
14,924
Regression analysis showed that participants’ expected payoff
27.8
10,054
11,350
Responder in Ultimatum Game
predicted almost completely the proportions of participants who
wanted
to play
with the
punisher.
Participants
chose
punishers
only when they expected to earn
Punisher
was
chosenso.
(%) = 103.80 + .0086  participants’ expected earnings from the
more by
doing
punisher - .0143  participant’s expected earnings from the non-punisher
(The only exception was when participants played the public goods
2 = .99
R
game)
Result: Behavior
Punisher
was
chosen
(%)
Punisher’s
expected payoff
per game play
Non-punisher’s
expected payoff
per game play
(yen)
(yen)
Dictator in Dictator Game
76.8
10,649
12,473
Prisoner’s dilemma game
69.2
8,596
6,875
Trustee in Trust Game
66.0
9,518
8,807
Proposer in Ultimatum Game
58.2
9,857
9,771
Truster in Trust Game
36.4
7,631
7,464
Recipient in Dictator Game
32.7
8,268
7,877
Public Goods Game
30.9
15,126
13,344
Responder in Ultimatum Game
27.8
9,946
8,298
Games in which a punisher
/ non-punisher plays
Punishers were expected to earn more in all situations except when
they play the dictator’s role in the dictator game.
➔ because participants would give the punisher more resources
than the non-punisher.
Punishers were not exploited when they were a recipient.
Result: Behavior
Games in which a punisher
/ non-punisher plays
Punisher
was
chosen
(%)
Punisher’s Non-punisher’s
expected payoff
expected payoff
per encounter
per encounter
(yen)
(yen)
Dictator in Dictator Game
76.8
7,804
2,286
Prisoner’s dilemma game
69.2
6,346
2,500
Trustee in Trust Game
66.0
6,585
3,264
Proposer in Ultimatum Game
58.2
5,855
4,200
Truster in Trust Game
36.4
2,964
4,873
Recipient in Dictator Game
32.7
2,964
4,655
Public Goods Game
30.9
4,736
9,855
Responder in Ultimatum Game
27.8
2,722
5,796
Taking into account the probability that participants chose the
punisher and the non-punisher as a game partner, punishers would
earn more than non-punishers only in games in which they provided
resources to the participant.
Summary of findings
■ Punishers were chosen more frequently as
providers of resources than were non-punishers
because they were perceived as more trustworthy and
fair.
Acquiring a reputation of being a punisher may pay off in
those games.
■ Punishers were chosen less frequently as recipients
of resources than were non-punishers.
Acquiring a reputation of being a punisher may not pay
off when the punisher plays those games.
Summary of findings
■ Punishers’ expected payoff per actual game
play was always higher than non-punishers’.
➔ Participants treated punishers better than
non-punishers when they were forced to play.
Discussion
Implications:
Punishers are likely to be chosen as game
players when trustworthiness and fairness are
needed.
➔ Candidate of a leader.
In addition, punishers are not likely to be
exploited.
Thank you for your attention.
Game type and the
punisher’s role in
the game
%
Punisher
was
chosen
Participant’s
earnings
from
punisher
Participant’s
earnings
from nonpunisher
Dictator in DG
76.81
9,3516
7,527
PDG player
69.2
9,385
7,946
Trustee in TG
66.0
9,232
8,386
Proposer in UG
58.2
9,071
8,473
Truster in TG
36.4
8,509
9,6797
Recipient in DG
32.7
11,732
12,123
PGG player
30.9
16,527
14,924
Responder in UG
27.8
10,054
11,350
Nonpunisher’ Punisher
s
’s
earnings earnings
per
per
game encounte
play
r
Nonpunisher
’s
earnings
per
encount
er
Participan
t’s
earnings
from
punisher
Participan
t’s
earnings
from nonpunisher
Game type
and the
punisher’s role
in the game
%
Punis
her
was
chose
n
Punishe
r’s
earning
s per
game
play
Dictator in DG
76.8
10,649
12,473
7,804
2,286
9,351
7,527
PDG player
69.2
8,596
6,875
6,346
2,500
9,385
7,946
Trustee in TG
66.0
9,518
8,807
6,585
3,264
9,232
8,386
Proposer in
UG
58.2
9,857
9,771
5,855
4,200
9,071
8,473
Truster in TG
36.4
7,631
7,464
2,964
4,873
8,509
9,679
Recipient in
DG
32.7
8,268
7,877
2,964
4,655
11,732
12,123
PGG player
30.9
15,126
13,344
4,736
9,855
16,527
14,924
Responder in
UG
27.8
9,946
8,298
2,722
5,796
10,054
11,350
Nonpunisher’s Punisher’s
earnings
earnings
per game
per
play encounter
Nonpunisher’
s
earnings
per
encounter
Participant’
s earnings
from
punisher
Participant’
s earnings
from nonpunisher
%
Game type and Punish
the punisher’s er was
role in the game chosen
Punisher’
s
earnings
per game
play
Dictator in DG
76.81
10,649
12,4733
7,8044
2,286
9,3516
7,527
PDG player
69.2
8,5962
6,875
6,346
2,500
9,385
7,946
Trustee in TG
66.0
9,518
8,807
6,585
3,264
9,232
8,386
Proposer in UG
58.2
9,857
9,771
5,855
4,200
9,071
8,473
Truster in TG
36.4
7,631
7,464
2,964
4,873
8,509
9,6797
Recipient in
DG
32.7
8,268
7,877
2,964
4,655
11,732
12,123
PGG player
30.9
15,126
13,344
4,736
9,8555
16,527
14,924
Responder in
UG
27.8
9,946
8,298
2,722
5,796
10,054
11,350
Nonpunisher’s Punisher’s
earnings
earnings
per game
per
play encounter
Nonpunisher’
s
earnings
per
encounter
Participant’
s earnings
from
punisher
Participant’
s earnings
from nonpunisher
%
Game type and Punish
the punisher’s er was
role in the game chosen
Punisher’
s
earnings
per game
play
Dictator in DG
76.81
10,649
12,4733
7,8044
2,286
9,3516
7,527
PDG player
69.2
8,5962
6,875
6,346
2,500
9,385
7,946
Trustee in TG
66.0
9,518
8,807
6,585
3,264
9,232
8,386
Proposer in UG
58.2
9,857
9,771
5,855
4,200
9,071
8,473
Truster in TG
36.4
7,631
7,464
2,964
4,873
8,509
9,6797
Recipient in
DG
32.7
8,268
7,877
2,964
4,655
11,732
12,123
PGG player
30.9
15,126
13,344
4,736
9,8555
16,527
14,924
Responder in
UG
27.8
9,946
8,298
2,722
5,796
10,054
11,350
Per game play: how much the punisher and the non-punisher each is expected to earn in each
game when it is played with the participant (columns 2 and 3 in Table 1).
Per encounter: We multiplied expected earnings per played game by the expected probability
that the game is played with the participant when he had a choice of the punisher and the nonpunisher as a game player.
The results of a principal component analysis of 25 impression items
Factor1
Factor2
Factor3
Factor4
“want to be a friend with”
.779
.144
.221
.214
“feel safe together”
.770
.237
.048
.044
“kind”
.690
.082
.270
-.092
“respected by people around”
.618
.309
.281
-.094
* “threatening”
-.491
-.101
-.153
.025
* “authoritarian”
-.583
.069
.292
-.153
“worthy of a leader”
.000
.811
-.130
.284
“relied on by people around”
.141
.778
.126
.019
“fair”
.101
.729
-.121
-.088
“justice minded”
.181
.726
.189
-.328
“socially desirable character”
.185
.662
.384
.011
“trustworthy”
.517
.544
-.042
.294
*“concerned only about own interest”
(reverse)
-.425
-.482
-.009
.341
Factor1
Factor2
Factor3
Factor4
“concerned about own
reputation”
-.068
.062
.736
-.126
“likely to get help from people
around”
.504
.023
.680
.006
“respective of group harmony”
.321
.018
.590
.031
“concerned about status
difference”
-.271
-.216
.535
.040
“respective of order within the
group”
.179
.479
.480
-.089
*“selfish”
-.353
-.249
-.431
-.251
*“conceited”
-.174
-.078
-.438
-.328
*“want to be number one”
-.422
-.153
-.465
-.174
*“hate losing”
-.297
-.086
-.580
-.173
“clever”
.000
.091
.067
.838
“get along well in society”
.044
-.060
.247
.792
*“meddling”
-.153
.300
.386
-.583
Public goods game condition. The booklet started with a description
of a public goods game in which four players―A, B, C and D―decided
how much of an endowment of 10,000 yen they would contribute to the
“common fund.” The money contributed to the common fund was
doubled by the experimenter and was equally allocated to the four
players. The scenario then stated that A and B (cooperators) contributed
all 10,000 yen to the common fund, whereas C and D (non-cooperators)
contributed nothing. As a result, both A and B earned 10,000 yen and C
and D earned 20,000 yen in this game. Participants received further
description of the game that the four players were provided with an
opportunity to monitor another player’s behavior, and to spend 2,000
yen to punish the monitored player. The punished player would be
confiscated 10,000 yen by the experimenter. One of the cooperators,
Player A (punisher), found out that Player C did not contribute any, and
spent 2,000 yen to punish C. The other cooperator, Player B (nonpunisher), also found out Player D did not contribute any, but did not
spend 2,000 yen to punish D. Player A is a cooperator and punisher and
Player B is a cooperator and non-punisher.
Third-party punisher condition. Participants first received a
description of a dictator game in which a dictator received 20,000
yen from the experimenter, and was asked to allocate the money
between himself and another player, a recipient. Two of the four
players, A and B, who played the role of dictator gave their
recipient a fair share of 10,000 yen, whereas the other two, C and
D, took all of 20,000 yen and gave their recipient nothing.
Participants were further informed that the participants were
provided with an opportunity to monitor another player’s behavior.
Player A found out that Player C took all the money, and spent
2,000 yen to punish C. Player B also found out that Player D took
all the money, but did not spend 2,000 yen to punish D.
Prisoner’s Dilemma Game (PD)
Prisoner’s Dilemma Game (PD)
Prisoners’ dilemma game situation. Participant was
asked to think of a situation in which he/she and either
Player A or Player B was each given an endowment of
5,000 yen from the experimenter, and decided whether or
not to give the money to the other. When one gives 5,000
yen, the other receives 10,000 yen. Following this
description of the game, participants were asked which of
the two players, Player A or B, they wanted to play this
game with. They were further asked whether or not
Player A would give his/her money to them, and whether
they themselves would give their money to A. They were
also asked the same set of questions concerning Player
B.
Public Goods Game (PGG)
Fund
Punisher
Fund
Non-punisher
Participant
Public Goods Game (PGG)
Public goods game situation. Participant would be a player in a four
person game in which four players were each given an endowment of
10,000 yen from the experimenter, and decided how much of it to
contribute to a “common fund.” The total sum of the money
contributed by the four members to the common fund was doubled by
the experimenter and equally allocated to the four players. Then, the
four players decided whether they would spend 2,000 yen to punish
other players who contributed nothing. Participants were asked to
choose which group they wanted to participate in, given a choice
between a group including Player A or another group including Player
B. They were further asked how much Player A would contribute to the
common fund, how much they themselves would contribute if they had
been a member of A’s group, and how much the other two members
would contribute. They were also asked the same set of questions
concerning B’s group.
Trust Game (TG)
Trustee
Truster
Trust game (trustee’s role). Participants were asked to
imagine themselves in the role of truster who decided
whether they would receive 5,000 yen directly from the
experimenter, or let their trustee partner (either Player A or
B) freely divide 20,000 yen between the truster and the
trustee. Following this description of the game, participants
were asked whether they wanted to play this game with
Player A or Player B. They were further asked which option
(sure 5,000 yen or a share of 20,000 yen) they would
choose if Player A was his/her partner, and how much
Player A would give to the partner if he/she was given a
chance to freely divide the money. They were also asked
the same set of questions concerning Player B as a
trustee.
Trust game (truster’s role). Either Player A or
Player B would decide whether he/she received 5,000
yen directly from the experimenter, or let the
participant freely divide 20,000 yen. Participants were
asked whether they wanted to play this game with
Player A or Player B. They were further asked which
option (sure 5,000 yen or a share of 20,000 yen)
Player A would choose if A was his/her partner, and
how much the participant would give to A if he/she
was given a chance to freely divide the money.
Participants were also asked the same set of
questions concerning Player B as a partner.
Ultimatum Game (UG)
Proposer
Responder
Ultimatum game (responder’s role). Participant would
receive 20,000 yen from the experimenter, and was asked to
decide how to divide the money between him/herself and
either Player A or Player B. Player A or B had an option to
accept the division or reject it. If he/she accepts the division,
both the participant and A or B would receive respective
shares of the money according to the player’s division. If
he/she rejected the division, neither party would receive any
money. Participants were asked whether they wanted to play
this game with Player A or B. They were further asked how
they would divide the money between themselves and Player
A, and if Player A would accept or reject their division. They
were also asked the same set of questions concerning Player
B as a partner.
Ultimatum game (proposer’s role). Either Player
A or Player B would receive 20,000 yen from the
experimenter, and was asked to decide how to divide
the money between him/herself and the participant.
The participant had an option to accept the division or
reject it. If he/she accepted the division, both the
participant and A or B would receive respective
shares of the money according to A’s or B’s division. If
he/she rejected the division, neither party would
receive any money. Participants were asked whether
they wanted to play this game with Player A or Player
B. They were further asked how Player A would divide
the money, and if they would accept or reject Player
A’s division. They were also asked the same set of
questions concerning Player B as a partner.
Dictator Game (DG)
Allocator
Recipient
Dictator game (recipient’s role).
The participant would receive 20,000
yen from the experimenter, and is asked
to decide how to divide the money
between him/herself and either Player A
or Player B. Participants were asked
whether they wanted to play this game
with Player A or Player B. They were
further asked how they would divide the
money between themselves and Player
A. They were also asked the same
question concerning Player B as a
partner.
Dictator game (dictator’s role). Either
Player A or Player B would receive 20,000
yen from the experimenter, and was asked
to decide how to divide the money
between him/herself and the participant.
Participants were asked whether they
wanted to play this game with Player A or
B. They were further asked how Player A
would divide the money between
him/herself and the participant. They were
also asked the same question concerning
Player B as a partner.