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Research Collection
Working Paper
A theory of reciprocity
Author(s): Falk, Armin; Fischbacher, Urs
Publication Date: 2000
Permanent Link: https://doi.org/10.3929/ethz-a-004372683
Rights / License: In Copyright - Non-Commercial Use Permitted
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ETH Library
Institute for Empirical Research in EconomicsUniversity of Zurich
Working Paper SeriesISSN 1424-0459
Working Paper No. 6
A Theory of Reciprocity
Armin Falk and Urs Fischbacher
July 2000
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+;,,1 Vhfrqg/ iru r�huv vpdoohu wkdq kdoi ri wkh slh wkh zloolqjqhvv wr dffhsw dq r�hu
lv lqfuhdvlqj lq wkh ohyho ri wkh r�hu dqg ghfuhdvlqj lq wkh uhvsrqghu*v frqfhuq iru
uhflsurflw|/ �2 +vhh wkh �uvw urz ri Htxdwlrq +;,,1 Iljxuh 5 ghslfwv wkh dffhswdqfh
suredelolw| dv d ixqfwlrq ri wkh ohyho ri wkh r�hu iru d jlyhq uhflsurfdo lqfolqdwlrq ri
wkh uhvsrqghu1 Wkh �jxuh qhdwo| fdswxuhv wkh hvvhqfh ri qhjdwlyh uhflsurflw|= Wkh
orzhu wkh r�hu/ wkh kljkhu lv wkh zloolqjqhvv ri d uhflsurfdoo| prwlydwhg uhvsrqghu wr
sxqlvk wkh sursrvhu e| uhmhfwlqj wkh r�hu1 Qrwh wkdw dv �2 jhwv kljkhu +orzhu, wkh
dffhswdqfh0fxuyh vkliwv wr wkh uljkw +ohiw,1
0
0.2
0.4
0.6
0.8
1
0 0.25 0.5 0.75 1offer c
acce
ptan
ce p
roba
bili
ty
c0
Iljxuh 5= Dffhswdqfh suredelolw| lq wkh xowlpdwxp jdph ghshqghqw rq wkh r�hu ri
wkh sursrvhu iru d jlyhq uhflsurflw| sdudphwhu ri wkh uhvsrqghu ri �2 @ 51
Zh qrz wxuq wr wkh sursrvhu1 Htxdwlrq +<, vkrzv wkdw klv htxloleulxp fkrlfh ri f
ghshqgv rq wzr h{suhvvlrqv1 Zkhuhdv wkh �uvw h{suhvvlrq ghshqgv rq wkh uhvsrqghu*v
uhflsurfdo lqfolqdwlrq/ l1h1/ rq �2/ wkh vhfrqg h{suhvvlrq ghshqgv rq wkh sursrvhu*v
frqfhuq iru uhflsurflw|/ l1h1/ rq ��1 Wkh vhfrqg h{suhvvlrq wkh sursrvhu*v lqwulqvlf
frqfhuq iru dq htxlwdeoh rxwfrph1 Li kh lv dq hjrlvwlf sod|hu wkh h{suhvvlrq lv }hur1 Li
�� lv odujh/ krzhyhu/ kh zloo r�hu d srvlwlyh f1 Wkh �uvw h{suhvvlrq fdq eh lqwhusuhwhg
dv dq h{wulqvlf frqvwudlqw wr r�hu d srvlwlyh f= Wklv h{suhvvlrq h{dfwo| gh�qhv wkh
vpdoohvw r�hu wkdw mxvw jxdudqwhhv dq dffhswdqfh suredelolw| ri 41 +Zh fdoo wklv
49
r�hu ff/ l1h1/ ff =@�n�423
s�nS42n4
22
e42/ frpsduh Iljxuh 5,1 Reylrxvo|/ wkh uhvsrqghu*v
frqfhuq iru uhflsurflw| lv fuxfldo iru wkh ydoxh ri ff1 Iru h{dpsoh/ li wkh uhvsrqghu lv
d vho�vk sod|hu +zlwk �2 @ 3, wkh ydoxh ri ff lv htxdo wr }hur1 Wkh kljkhu sod|hu 5*v
frqfhuq iru uhflsurflw|/ wkh kljkhu wkh ydoxh ri ff1 Dv �2 jhwv yhu| odujh/ ff dssurdfkhv�2 1 Wkh ghshqghqfh ri ff rq �2 lv vkrzq lq Iljxuh 61 Lw lv uhpdundeoh wkdw hyhq iru
vpdoo ydoxhv ri �2 wkh sursrvhu lv cirufhg* wr pdnh d udwkhu jhqhurxv r�hu lq rughu wr
dyrlg d uhmhfwlrq1
Wkh htxloleulxp r�hu fW lv wkh pd{lpxp ri wkh �uvw dqg wkh vhfrqg h{suhvvlrq
ri Htxdwlrq +<,= Wklv phdqv/ h1j1/ wkdw lq fdvh d vho�vk sursrvhu sod|v djdlqvw d
uhflsurfdo uhvsrqghu kh zloo r�hu wkh pruh/ wkh kljkhu �21 Lq wklv fdvh wkh h{wulqvlf
frqvwudlqw lv elqglqj1 Li/ krzhyhu/ wkh uhvsrqghu kdv d yhu| orz �2/ l1h1/ kh dffhswv
sudfwlfdoo| dq| r�hu/ wkh htxloleulxp r�hu lv ghwhuplqhg e| wkh sursrvhu*v frqfhuq
iru dq htxlwdeoh rxwfrph= Li kh lv udwkhu vho�vk wrr/ klv r�hu zloo eh +forvh wr, }hur1
Li/ rq wkh rwkhu kdqg/ �� lv udwkhu kljk/ wkh r�hu zloo eh kljk dv zhoo147
0
0.1
0.2
0.3
0.4
0.5
0 1 2 3 4reciprocity parameter of the responder
Iljxuh 6= R�huv lq wkh xowlpdwxp jdph wkdw jxdudqwhh dq dffhswdqfh zlwk suredelolw|
4/ ghshqghqw rq wkh wkh uhflsurflw| sdudphwhu ri wkh uhvsrqghu +�2,1
71414 Wkh uroh ri lqwhqwlrqv
Ehiruh zh wxuq wr wkh qh{w jdph zh zloo eulh | glvfxvv wkh suhglfwlrqv ri rxu wkhru|
iru wkh qrq0lqwhqwlrqdo wuhdwphqw uhsruwhg e| Eorxqw +4<<8,1 Lq khu wuhdwphqw wkh
sursrvhuv* r�huv zhuh qrw fkrvhq e| kxpdq vxemhfwv exw lqvwhdg udqgrpo| vhohfwhg1
Frqvhtxhqwo|/ d orz r�hu glg qrw vljqdo dq| +edg, lqwhqwlrqv1 Dv wkh gdwd ri Eorxqw*v
47Wkh udqjh ri 4�0 dqg 420 frpelqdwlrqv zkhuh wkh htxloleulxp r�hu SW htxdov Sf lv jlyhq e|
42 D 44E443��
44n�1 Wklv krogv lq sduwlfxodu li 42 D 4�1
4:
h{shulphqw uhyhdov/ wkh dffhswdqfh udwh iru d jlyhq r�hu lv pxfk kljkhu wkdq lq wkh
cuhjxodu* wuhdwphqw1 Krzhyhu/ hyhq lq wkh devhqfh ri lqwhqwlrqv vrph vxemhfwv uhmhfw
h{wuhpho| glvdgydqwdjhrxv r�huv1 Rxu wkhru| suhglfwv h{dfwo| wkhvh wzr vw|ol}hg idfwv1
Lq wkh qrq0lqwhqwlrqdo wuhdwphqw wkh htxloleulxp dffhswdqfh udwh iru sW lv jlyhq e|=
sW @
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2
4 li f � �2
Iljxuh 7 ghslfwv wkh suhglfwhg dffhswdqfh suredelolwlhv lq wkh cuhjxodu* xowlpdwxp
jdph dqg lq Eorxqw*v wuhdwphqw iru d jlyhq �21 Wkh xsshu judsk fruuhvsrqgv wr
wkh Eorxqw0h{shulphqw zkhuhdv wkh orzhu judsk vkrzv wkh dffhswdqfh ehkdylru lq wkh
cuhjxodu* wuhdwphqw1 Dv fdq eh vhhq lq wkh �jxuh/ d uhvsrqghu*v dffhswdqfh suredelolw|
iru orz r�huv lv kljkhu li lqwhqwlrqv duh devhqw1
Wkh orzhu wkh rxwfrph frqfhuq sdudphwhu %2/ wkh pruh wkh xsshu judsk vkliwv wr
wkh ohiw1 Sxw gl�huhqwo|/ wkh pruh d uhvsrqghu lv frqfhuqhg zlwk lqwhqwlrqv uhodwlyh wr
rxwfrphv/ wkh pruh olnho| vkh zloo dffhsw yhu| orz r�huv lq Eorxqw*v qrq0lqwhqwlrqdo
wuhdwphqw1 Rq wkh rwkhu kdqg/ li d uhvsrqghu lv sxuho| rxwfrph rulhqwhg/ l1h1/ li %2 @ 4
krogv/ vkh h{klelwv wkh vdph ehkdylrudo sdwwhuq dv lq wkh cuhjxodu* wuhdwphqw1 Dv wkh
gdwd uhyhdov/ krzhyhu/ shrsoh fduh derxw lqwhqwlrqv +l1h1/ %� ? 4,1
0
0.2
0.4
0.6
0.8
1
0 0.25 0.5 0.75 1offer c
random offer
intentional offer
Iljxuh 7= Dffhswdqfh suredelolwlhv lq wkh xowlpdwxp jdph zlwk lqwhqwlrqv +orzhu
judsk, dqg zlwkrxw lqwhqwlrqv +xsshu judsk, ghshqghqw rq wkh r�hu1 Wkh sdudphwhuv
�2 @ 5 dqg %2 @ 3=5 duh jlyhq1
4;
715 Srvlwlyh uhflsurflw|= Wkh jliw0h{fkdqjh jdph
Pdq| h{shulphqwv kdyh ghprqvwudwhg wkh lpsruwdqfh ri srvlwlyh uhflsurflw|1 Rqh zhoo
nqrzq h{shulphqw lv wkh jliw0h{fkdqjh jdph1 Lq wklv wzr0shuvrq vhtxhqwldo jdph/
wkh �uvw pryhu +fdoohg dq hpsor|hu, r�huv d zdjh z wr d vhfrqg pryhu +fdoohg d
zrunhu,1 Wkh zrunhu fdq hlwkhu wdnh lw ru ohdyh lw +vhh h1j1/ Ihku/ Jçfkwhu dqg
Nlufkvwhljhu +4<<:,,1 Li wkh zrunhu uhmhfwv/ erwk hduq qrwklqj1 Li wkh zrunhu
wdnhv wkh zdjh r�hu/ vkh kdv wr pdnh dq h�ruw ghflvlrq h1 Surylglqj h�ruw deryh wkh
plqlpxp h�ruw ohyho lv frvwo| zlwk f+h, ehlqj d frqyh{ h�ruw frvw ixqfwlrq1 Sd|r�
ixqfwlrqv duh jlyhq e| �� @ yh � z iru hpsor|huv dqg �2 @ z � f+h, iru zrunhuv/
uhvshfwlyho|1 D udwlrqdo dqg vho�vk zrunhu zloo 0 luuhvshfwlyh ri wkh zdjh sdlg 0
fkrrvh wkh plqlpxp h�ruw ohyho1 Zlwk edfnzdug lqgxfwlrq/ wkh hpsor|hu zloo r�hu
rqo| wkh orzhvw srvvleoh zdjh1 Frqwudu| wr wklv suhglfwlrq wkh pdlq h{shulphqwdo
�qglqjv duh +l, wkdw zdjhv fohduo| h{fhhg wkh orzhvw srvvleoh zdjh dqg +ll, wkdw wkhuh
lv d srvlwlyh zdjh0h�ruw uhodwlrq1 Erwk �qglqjv duh uhpdundeo| urexvw1 Wkh| krog lq
elodwhudo lqvwlwxwlrqv dv zhoo dv lq frpshwlwlyh pdunhw lqvwlwxwlrqv +vhh/ h1j1/ Ihku/
Nlufkvwhljhu dqg Ulhgo +4<<6,/ Ihku dqg Idon +4<<<, dqg Jçfkwhu dqg
Idon +4<<:,,1
Lq rxu dqdo|vlv zh uhvwulfw z 5 ^3> 4`/ h 5 ^3> 4`/ zh qrupdol}h y wr 4 dqg zulwh
wkh frqyh{ h�ruw frvw ixqfwlrq dv f+h, @ �h2 zlwk � � �e 1 Wr hdvh wkh sursrvlwlrq ri
wkh htxloleuld lq wkh jliw0h{fkdqjh jdph/ zh xvh wkh iroorzlqj gh�qlwlrqv1 Iluvw/ ohwhz+�> ��> �2, eh wkh zdjh wkdw zrxog eh fkrvhq e| wkh hpsor|hu li z dqg h zrxog qrw
eh uhvwulfwhg wr eh vpdoohu wkdq 41 Wkh h{dfw irupxod iru hz+�> ��> �2, lv jlyhq lq wkh
surri ri wkh sursrvlwlrq1 Zh ixuwkhu gh�qh z+�> �2, @�n@2 . @
42zklfk lv wkh plqlpdo
zdjh wkdw jxdudqwhhv dq h�ruw fkrlfh ri rqh1 Wkh iroorzlqj sursrvlwlrq qrz vkrzv
wkdw wkh vw|ol}hg idfwv ri wkh jliw0h{fkdqjh jdph duh uhsolfdwhg e| rxu wkhru|=
Sursrvlwlrq 5 Lq wkh jliw0h{fkdqjh jdph wkhuh duh wkh iroorzlqj uhflsurflw| htxloleuld
+zW> hW,=
+l, Li �2 @ 3/ wkhq wkhuh h{lvwv d xqltxh htxloleulxp=
zW @ hW @ 3 +43,
+ll, Li �2 A 3/ wkhq
hW @
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s+5�. �2,
2 . ;��22z
5��2
&�o+44,
Wkhuh lv dozd|v dq htxloleulxp jlyhq e|=
zW @ ^plq +z+�> �2,> hz+�> ��> �2,,`�odf +45,
4<
Li %��� � 42E342n2kn2k42�2kE32k342n2k42�
dqg z+�> �2, � 4> wkhq wkhuh lv d vhfrqg htxloleulxp
zklfk lv jlyhq e|=
zW @ z+�> �2,
Wkh surri ri Sursrvlwlrq 5 lv jlyhq lq Dsshqgl{ 61
Glvfxvvlrq= Zh looxvwudwh Sursrvlwlrq 5 zlwk wkh khos ri Iljxuhv 8 wr :1 Lq
Iljxuh 8 zh ghslfw krz 0 lq htxloleulxp 0 d zrunhu*v h�ruw fkrlfh ghshqgv rq wkh
zdjh sdlg e| wkh hpsor|hu jlyhq khu uhflsurfdo prwlydwlrq/ �2 +frpsduh htxdwlrq
+44, ri Sursrvlwlrq 5,1 Wklv �jxuh qhdwo| fdswxuhv wkh hvvhqfh ri srvlwlyh uhflsurflw|
dv uhsruwhg lq wkh jliw0h{fkdqjh h{shulphqwv1 Uhflsurfdo zrunhuv surylgh kljkhu
h�ruw ohyhov wkh kljkhu wkh zdjh sdlg e| cwkhlu* hpsor|huv1 Pruhryhu/ zrunhuv zloo 0
iru d jlyhq zdjh 0 fkrrvh kljkhu h�ruw ohyhov/ wkh vwurqjhu wkhlu uhflsurfdo lqfolqdwlrq
+frpsduh htxdwlrq 44,1 Wklv uhodwlrqvkls lv ghslfwhg lq Iljxuh 91 Wkh xsshu judsk
vkrzv wkh htxloleulxp h�ruw fkrlfh iru d zdjh z @ 3=8/ zkhuhdv wkh orzhu ghslfwv wkh
rswlpdo h�ruw iru d orzhu zdjh +z @ 3=6,1 Qrwh wkdw wkh h�ruw ohyho lv }hur li dqg
rqo| li �2 @ 3 ru z @ 31
0
0.2
0.4
0.6
0.8
1
0 0.2 0.4 0.6 0.8 1wage
Iljxuh 8= H�ruw fkrlfh ghshqghqw rq wkh zdjh sdlg iru d jlyhq �2 dqg d jlyhq �
+�2 @ 5 dqg � @ 3=5,1
Krz fdq zh fkdudfwhul}h dq hpsor|hu*v rswlpdo fkrlfh/ jlyhq d zrunhu*v h�ruw
ehkdylruB Lq Iljxuh : zh vkrz krz wkh htxloleulxp zdjh ghshqgv rq �2 +iru d jlyhq
��,1 Lq htxloleulxp/ dq hpsor|hu zloo 0 iru d vpdoo �2 0 r�hu d zdjh htxdo wr }hur zklfk
dovr lpsolhv dq h�ruw fkrlfh ri }hur1 Li/ krzhyhu/ wkh zrunhu lv vx!flhqwo| uhflsurfdo
wkh zdjh r�hu lqfuhdvhv lq �2148 Qrwlfh lq Iljxuh : wkdw wklv lqfuhdvh vwrsv dv �2
48Dv fdq eh vhhq lq Iljxuh : wkhuh lv dq lqwhuphgldwh udqjh ri 42 zkhuh wzr htxloleuld h{lvw1 Wkh
htxloleulxp fruuhvsrqglqj wr wkh xsshu eudqfk lv ghvfulehg ehorz1
53
0
0.2
0.4
0.6
0.8
1
0 1 2 3 4reciprocity parameter of the worker ( ρ2)
effo
rt
w=.5
w=.3
Iljxuh 9= Htxloleulxp h�ruw fkrlfh ghshqghqw rq wkh zrunhu*v uhflsurflw| sdudphwhu
�2 d jlyhq � dqg wzr zdjh ohyhov +� @ =5/ z @ =6 dqg z @ =8,1
uhdfkhv d sduwlfxodu ohyho1 Dw wklv ohyho wkh hpsor|hu jhwv wkh pd{lpdo h�ruw ohyho1
Wkxv/ lw pdnhv qr vhqvh wr sd| d kljkhu zdjh/ qhlwkhu iru d uhflsurfdo qru iru d vho�vk
hpsor|hu1 Wr wkh frqwudu|/ dv �2 jhwv kljkhu wkh orzhvw zdjh wkdw jxdudqwhhv wkh
pd{lpdo h�ruw ohyho dfwxdoo| ghfuhdvhv1
Krz grhv wkh hpsor|hu*v frqfhuq iru uhflsurflw| �� lq xhqfh lwv ghflvlrqB Wr
dqvzhu wklv txhvwlrq qrwlfh �uvw wkdw wkh zrunhu fdq dozd|v hqvxuh dw ohdvw dq htxdo
vkduh iru khuvhoi/ l1h1/ wkh hpsor|hu lv dozd|v lq d glvdgydqwdjhrxv vlwxdwlrq1 Zkhuhdv
d vx!flhqwo| vho�vk hpsor|hu grhv qrw erwkhu derxw wklv/ d uhflsurfdo hpsor|hu grhv1
Frqvhtxhqwo|/ iru vpdoo �� dq hpsor|hu sd|v wkh sur�w pd{lpl}lqj zdjh1 Dv �� jhwv
kljkhu/ krzhyhu/ wkh hpsor|hu dfwxdoo| sd|v d orzhu zdjh 0 gxh wr wkh lpsdfw ri
qhjdwlyh uhflsurflw|1
Iljxuh : uhyhdov dqrwkhu lqwhuhvwlqj ihdwxuh ri Sursrvlwlrq 5= Iru vx!flhqwo| kljk
�� wkhuh lv dq lqwhuphgldwh udqjh ri �2 zkhuh wzr htxloleulxp zdjhv h{lvw1 Lq wkh
htxloleulxp fruuhvsrqglqj wr wkh xsshu eudqfk wkh hpsor|hu sd|v d zdjh wkdw jxdu0
dqwhhv dq h�ruw ri 41 Wklv htxloleulxp fdq eh ghvfulehg dv iroorzv= Wkh hpsor|hu
h{shfwv wr jhw dq h�ruw ri 4/ l1h1/ wkh pd{lpxp h�ruw ohyho1 Wklv phdqv wkdw wkh
zrunhu frxog qrw kdyh fkrvhq d kljkhu h�ruw ohyho1 Wkxv/ hyhq wkrxjk wkh hpsor|hu
lv lq d glvdgydqwdjhrxv vlwxdwlrq kh fdqqrw lqihu wkdw wkh zrunhu zdqwhg wr wuhdw wkh
hpsor|hu xqnlqgo|1 Dv d frqvhtxhqfh wkh hpsor|hu grhv qrw kdyh wkh ghvluh wr sxqlvk
wkh zrunhu dqg wkhuhiruh fkrrvhv wkh sd|r� pd{lpl}lqj zdjh/ l1h1/ d udwkhu kljk zdjh
wkdw jxdudqwhhv dq h�ruw ohyho ri 41 Lq wkh htxloleulxp fruuhvsrqglqj wr wkh orzhu
eudqfk lq Iljxuh :/ wkh hpsor|hu h{shfwv wkdw wkh zrunhu surylghv dq h�ruw vwulfwo|
ehorz 41 Wklv htxloleulxp pd| frh{lvw zlwk wkh iruphu iru wkh iroorzlqj uhdvrq= Wkh
54
idfw wkdw wkh zrunhu fkrrvhv dq h�ruw vpdoohu wkdq 4 lv frqvlghuhg dv yhu| xqnlqg
vlqfh vkh frxog kdyh fkrvhq d +voljkwo|, kljkhu h�ruw ohyho1 Wkhuhiruh/ wkh +uhflsurfdo,
hpsor|hu kdv dq lqfhqwlyh wr sxqlvk wkh zrunhu/ l1h1/ wr sd| d orz zdjh1 Wklv orz
zdjh qrz lqgxfhv wkh zrunhu wr surylgh wkh orz h�ruw ohyho wkh hpsor|hu h{shfwhg1
Lq d fhuwdlq vhqvh wkh hpsor|hu*v htxloleulxp ehkdylru fdq eh xqghuvwrrg dv d nlqg ri
�vhoi ixo�oolqj surskhf|�= Li wkh hpsor|hu eholhyhv wkdw wkh zrunhu lv qlfh/ wkh zrunhu
zloo lqghhg eh qlfh1 Li/ rq wkh rwkhu kdqg/ wkh hpsor|hu eholhyhv wkdw wkh zrunhu lv
phdq/ wkh zrunhu zloo lq idfw ehkdyh dffruglqjo|1
0
0.2
0.4
0.6
0.8
1
0 1 2 3 4
reciprocity parameter of player 2 (worker)
Iljxuh := Htxloleulxp zdjh r�hu ghshqghqw rq �2 iru d jlyhq �� dqg � +�� @ 5 dqg
� @ 3=5,1 Wkh orzhu eudqfk fruuhvsrqgv wr htxloleuld zlwk hW ? 4 zkhuhdv lq wkh
xsshu eudqfk hW @ 4 krogv1
71514 Wkh uroh ri lqwhqwlrqv
Frqfoxglqj rxu glvfxvvlrq ri wkh jliw0h{fkdqjh jdph zh suhvhqw rxu suhglfwlrqv iru
wkh wuhdwphqw uhsruwhg e| Fkduqhvv +4<<9,1 Lq klv h{shulphqw zdjhv duh qrw gh0
whuplqhg e| wkh shuvrq wkh zrunhu lv lqwhudfwlqj zlwk1 Udwkhu/ d wklug sduw| ru d
udqgrp phfkdqlvp ghwhuplqhv wkh zdjh1 Frpsduhg wr wkh cuhjxodu* wuhdwphqw/ wklv
ohdgv wr d zhdnhu fruuhodwlrq ehwzhhq zdjhv dqg h�ruw ohyhov1 Wkh uhdvrq lv wkdw
lq Fkduqhvv* wuhdwphqw d kljk zdjh grhv qrw vljqdo dq| +nlqg, lqwhqwlrqv1 Zkhuhdv
sxuho| rxwfrph rulhqwhg prghov fdqqrw glvwlqjxlvk ehwzhhq wkhvh wzr wuhdwphqwv/
rxu wkhru| grhv1 Iru d jlyhq uhflsurfdo prwlydwlrq �2 zh suhglfw d zhdnhu fruuhodwlrq
ehwzhhq zdjhv dqg h�ruw ohyhov1 Wklv phdqv wkdw wkh vdph zrunhu zloo vxsso| d
orzhu h�ruw iru d sduwlfxodu uhfhlyhg zdjh lq wkh udqgrp0wuhdwphqw frpsduhg wr wkh
cuhjxodu* wuhdwphqw1 Iljxuh ; vkrzv wkdw uhvxow1
55
0
0.2
0.4
0.6
0.8
1
0 0.2 0.4 0.6 0.8 1wage
intentional wage
random wage
Iljxuh ;= Htxloleulxp h�ruw ghshqghqw rq wkh zdjh1 Lq wkh xsshu judsk/ wkh zdjh
lv fkrvhq e| d kxpdq ehlqj/ lq wkh orzhu judsk d udqgrp zdjh lv jlyhq1 +%2 @ 3=5>
� @ 3=5,
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Zdwdeh/ P1/ Whudl/ V1/ Kd|dvkl/ Q1/ dqg \dpdjlvkl/ W1 +4<<9,= �Frrshudwlrq lqwkh Rqh0Vkrw Sulvrqhu*v Glohppd Edvhg rq H{shfwdwlrqv ri Uhflsurflw|�/ MdsdqhvhMrxuqdo ri H{shulphqwdo Vrfldo Sv|fkrorj|/ [[[YL/ 4;604<91
78
The Working Papers of the Institute for Empirical Research in Economics can be downloaded in PDF-format fromhttp://www.unizh.ch/iew/wp/
Institute for Empirical Research in Economics, Blümlisalpstr. 10, 8006 Zurich, Switzerland
Phone: 0041 1 634 37 05 Fax: 0041 1 634 49 07 E-mail: [email protected]
Working Papers of the Institute for Empirical Research in Economics
No.1. Rudolf Winter-Ebmer and Josef Zweimüller: Firm Size Wage Differentials in Switzerland: Evidence from Job
Changers, February 19992. Bruno S. Frey and Marcel Kucher: History as Reflected in Capital Markets: The Case of World War II, February
19993. Josef Falkinger, Ernst Fehr, Simon Gächter and Rudolf Winter-Ebmer: A Simple Mechanism for the Efficient
Provision of Public Goods – Experimental Evidence, February 19994. Ernst Fehr and Klaus M. Schmidt: A Theory of Fairness, Competition and Cooperation, April 19995. Markus Knell: Social Comparisons, Inequality, and Growth, April 19996. Armin Falk and Urs Fischbacher: A Theory of Reciprocity, July 20007. Bruno S. Frey and Lorenz Goette: Does Pay Motivate Volunteers?, May 19998. Rudolf Winter-Ebmer and Josef Zweimüller: Intra-firm Wage Dispersion and Firm Performance, May 19999. Josef Zweimüller: Schumpeterian Entrepreneurs Meet Engel’s Law: The Impact of Inequality on Innovation-
Driven Growth, May 199910. Ernst Fehr and Simon Gächter: Cooperation and Punishment in Public Goods Experiments, June 199911. Rudolf Winter-Ebmer and Josef Zweimüller: Do Immigrants Displace Young Native Workers: The Austrian
Experience, June 199912. Ernst Fehr and Jean-Robert Tyran: Does Money Illusion Matter?, June 199913. Stefan Felder and Reto Schleiniger: Environmental Tax Reform: Efficiency and Political Feasibility, July 199914. Bruno S. Frey: Art Fakes – What Fakes?, An Economic View, July 199915. Bruno S. Frey and Alois Stutzer: Happiness, Economy and Institutions, July 199916. Urs Fischbacher, Simon Gächter and Ernst Fehr: Are People Conditionally Cooperative? Evidence from a Public
Goods Experiment, July 200017. Armin Falk, Ernst Fehr and Urs Fischbacher: On the Nature of Fair Behavior, August 199918. Vital Anderhub, Simon Gächter and Manfred Königstein: Efficient Contracting and Fair Play in a Simple
Principal-Agent Experiment, September 200019. Simon Gächter and Armin Falk: Reputation or Reciprocity?, September 199920. Ernst Fehr and Klaus M. Schmidt: Fairness, Incentives, and Contractual Choices, September 199921. Urs Fischbacher: z-Tree - Experimenter’s Manual, September 199922. Bruno S. Frey and Alois Stutzer: Maximising Happiness?, October 199923. Alois Stutzer: Demokratieindizes für die Kantone der Schweiz, October 199924. Bruno S. Frey: Was bewirkt die Volkswirtschaftslehre?, October 199925. Bruno S. Frey, Marcel Kucher and Alois Stutzer: Outcome, Process & Power in Direct Democracy, November
199926. Bruno S. Frey and Reto Jegen: Motivation Crowding Theory: A Survey of Empirical Evidence, November 199927. Margit Osterloh and Bruno S. Frey: Motivation, Knowledge Transfer, and Organizational Forms, November 199928. Bruno S. Frey and Marcel Kucher: Managerial Power and Compensation, December 199929. Reto Schleiniger: Ecological Tax Reform with Exemptions for the Export Sector in a two Sector two Factor Model,
December 199930. Jens-Ulrich Peter and Klaus Reiner Schenk-Hoppé: Business Cycle Phenomena in Overlapping Generations
Economies with Stochastic Production, December 199931. Josef Zweimüller: Inequality, Redistribution, and Economic Growth, January 200032. Marc Oliver Bettzüge and Thorsten Hens: Financial Innovation, Communication and the Theory of the Firm,
January 200033. Klaus Reiner Schenk-Hoppé: Is there a Golden Rule for the Stochastic Solow Growth Model? January 200034. Ernst Fehr and Simon Gächter: Do Incentive Contracts Crowd out Voluntary Cooperation? February 200035. Marc Oliver Bettzüge and Thorsten Hens: An Evolutionary Approach to Financial Innovation, July 200036. Bruno S. Frey: Does Economics Have an Effect? Towards an Economics of Economics, February 200037. Josef Zweimüller and Rudolf Winter-Ebmer: Firm-Specific Training: Consequences for Job-Mobility, March 2000
Working Papers of the Institute for Empirical Research in Economics
No.
The Working Papers of the Institute for Empirical Research in Economics can be downloaded in PDF-format fromhttp://www.unizh.ch/iew/wp/
Institute for Empirical Research in Economics, Blümlisalpstr. 10, 8006 Zürich, Switzerland
Phone: 0041 1 634 37 05 Fax: 0041 1 634 49 07 E-mail: [email protected]
38. Martin Brown, Armin Falk and Ernst Fehr: Contract Inforcement and the Evolution of Longrun Relations, March2000
39. Thorsten Hens, Jörg Laitenberger and Andreas Löffler: On Uniqueness of Equilibria in the CAPM, July 200040. Ernst Fehr and Simon Gächter: Fairness and Retaliation: The Economics of Reciprocity, March 200041. Rafael Lalive, Jan C. van Ours and Josef Zweimüller: The Impact of Active Labor Market Programs and Benefit
Entitlement Rules on the Duration of Unemployment, March 200042. Reto Schleiniger: Consumption Taxes and International Competitiveness in a Keynesian World, April 200043. Ernst Fehr and Peter K. Zych: Intertemporal Choice under Habit Formation, May 200044. Ernst Fehr and Lorenz Goette: Robustness and Real Consequences of Nominal Wage Rigidity, May 200045. Ernst Fehr and Jean-Robert Tyran: Does Money Illusion Matter? REVISED VERSION, May 200046. Klaus Reiner Schenk-Hoppé: Sample-Path Stability of Non-Stationary Dynamic Economic Systems, Juni 200047. Bruno S. Frey: A Utopia? Government without Territorial Monopoly, June 200048. Bruno S. Frey: The Rise and Fall of Festivals, June 200049. Bruno S. Frey and Reto Jegen: Motivation Crowding Theory: A Survey of Empirical Evidence, REVISED
VERSION, June 200050. Albrecht Ritschl and Ulrich Woitek: Did Monetary Forces Cause the Great Depression? A Bayesian VAR Analysis
for the U.S. Economy, July 200051. Alois Stutzer and Rafael Lalive: The Role of Social Work Norms in Job Searching and Subjective Well-Being, July
200052. Iris Bohnet, Bruno S. Frey and Steffen Huck: More Order with Less Law: On Contract Enforcement, Trust, and
Crowding, July 200053. Armin Falk and Markus Knell: Choosing the Joneses: On the Endogeneity of Reference Groups, July 200054. Klaus Reiner Schenk-Hoppé: Economic Growth and Business Cycles: A Critical Comment on Detrending Time
Series, August 200055. Armin Falk, Ernst Fehr and Urs Fischbacher: Appropriating the Commons – A Theoretical Explanation, September
200056. Bruno S. Frey and Reiner Eichenberger: A Proposal for a Flexible Europe, August 200057. Reiner Eichenberger and Bruno S. Frey: Europe’s Eminent Economists: A Quantitative Analysis, September 200058. Bruno S. Frey: Why Economists Disregard Economic Methodology, September 200059. Armin Falk, Ernst Fehr, Urs Fischbacher: Informal Sanctions, September 200060. Rafael Lalive: Did we Overestimate the Value of Health?, October 200061. Matthias Benz, Marcel Kucher and Alois Stutzer: Stock Options: the Managers’ Blessing. Institutional Restrictions
and Executive Compensation, October 2000