free-riding and intergroup moblitily jun kobayashi (chicago) hideki fujiyama (dokkyo) yuhsuke koyama...

FREE-RIDING and

INTERGROUP MOBLITILY

Jun Kobayashi (Chicago)Hideki Fujiyama (Dokkyo)Yuhsuke Koyama (Tokyo Tech)Hirokuni Ooura (Teikyo)

August 16, 2004ASA, San Francisco

OVERVIEW

Free-riding and Mobility?

Experiment w/ Exit Option

Macro Dynamics and Micro Behavior

3

Modern Societies... MOBILITY Turnover, Divorce, Moving, Immigration

Globalization, Internet

QUESTION

Effects of MOBILITY on FREE-RIDING???

4

RATIONAL to FREE-RIDEbut EFFICIENT to COOPERATE

(Externality)

Promise, DonationTeamwork, Social Movement

FREE-RIDER PROBLEM

ON the RUN (Erhart-Keser) Experiment, 9 in initial 3 groups Cooperators “ESCAPE”

(Group) CirculationCooperation↑ -> Size↑ -> C↓-> S↓

(Individual) Avoid Free-ridersCooperator↑ -> Leave S↑, Enter S↓

Various Conditions???

Introduction

Data

Result

7

2003/4, 4 universities in Japan 14 Sessions, 234 students 1289.0 yens ($11), 90 minutes Computer-based, Group data

NO Mobility LOW/ HIGH/ COMPLETE Mobility

16-7 in 4 Groups, Anonymous 50 Rounds， 9 Pauses/Exit chances

EXPERIMENT

8

9

GAMEA B C D

Pause/Exit

Free-rider Problem

10

Resource 20 yensPROVIDE or NOT

Pooled Resources...DOUBLED...3/more-player groupsx 1.5... 2-player GroupsSAME... 1-player Groups

EQUALLY Distributed in Group

1. FREE-RIDER PROBLEM

11

Provide = 40m / 4 (Providers) Not = 40(m-1) / 4 + 20

NotProvide

NotNot

x 2 =

EXAMPLE (4 PLAYERS)

12

NO Mobility... PAUSE

LOW Mobility... 50 yens to Exit

HIGH Mobility... 20 yens

Complete Mobility... 0 yen

2. PAUSE or EXIT

A　 33.3

3

B　 25.0

0

C　 27.5

0

D　 25.0

0

A　 33.3

3

B　 25.0

0

C　 27.5

0

D　 25.0

0

A　

3

B 4

C 8

D　

2

Groups’ Average PayoffsLast Round

Groups’ Average Payoffsin This Block

Groups’ Size

Group C Block 2 Round 2Your Decisions and Payoffs in This Block

Round Your Decision Your Payoff

1 NOT 35.00

2 PROVIDE 　 5.00

Your Total: 125 yens(20 yens subtracted for Moving)

Group C's Members: You (ID 6) and Other 7

What do you do this round?

PROVIDE 20 yens

NOT

Provided 20 yens: 3 persons

Not: 4 persons

Your Decision: Provide

Your Payoff: 17.14 yens

Groups’ Average PayoffsLast Block, Size

BLOCK END

Groups’ Average Payoffs

Group Round 1 2 3 4 5

A 　 33.33　 20.0

0　 15.5

5　 24.7

635.00

B 　 25.00　 35.0

0　 19.1

0　 35.0

035.00

C 　 27.50　 27.5

0　 22.0

0　 27.5

020.00

D 　 25.00　 35.0

0　 25.0

0　 25.0

018.88Your payoff Last Block: 112 yens in Group C

Click to Next

A　 30.0

03

B　 33.3

34

C　 25.0

08

D　 27.5

02

A　 30.0

03

B　 33.3

34

C　 25.0

08

D　 27.5

02

Groups’ Average PayoffsLast Block, Size

BLOCK END

Groups’ Average Payoffs

Group Round 1 2 3 4 5

A 　 33.33　 20.0

0　 15.5

5　 24.7

635.00

B 　 25.00　 35.0

0　 19.1

0　 35.0

035.00

C 　 27.50　 27.5

0　 22.0

0　 27.5

020.00

D 　 25.00　 35.0

0　 25.0

0　 25.0

018.88Your payoff Last Block: 112 yens in Group C

Which Group in Next Block? Move with 50 yens

Group A

B

C

D

Introduction

Data

Result

18

Cooperation DECREASES

RoundsCoo

pera

tion

0.20

0.25

0.30

0.35

0.40

0.45

0.50

0.55

0.00 0.20 0.40 0.60 0.80

Mobility

y = GROUP SIZE

N=360 (Groups in Blocks)

Group Cooperation↑ -> Size↑

Model 1 2BLOCK (1-10) .001 .002PREVIOUS SIZE -.602***PREVIOUS C .163** .356***Adjusted R2 .021 .347

y = GROUP COOPERATION

Group Size↑ -> Cooperation↓

Model 1 2BLOCK -.059 -.061PREVIOUS C .232***PREVIOUS SIZE -.143*CURRENT SIZE -.377*** -.269***Adjusted R2 .164 .127

LEAVE and ENTERCorrelations with COOPERATION

N=505 (Individual Mobility)

Cooperators Leave LARGE Groups Enter SMALL Groups

(to Avoid Free-riders)

Group Size rPREVIOUS Size, Left .041PREVIOUS Size, Entered -.141**

22

Mobility DECREASES Cooperation

Cooperative Groups EXPAND, then DECREASE Cooperation Cooperators Enter SMALL Groups

Differences b/w CONDITIONS? Role of SANCTION?

SUMMARY