a game theoretic approach to north south collaboration ekko van ierland wageningen university based...
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A Game Theoretic Approach to North
South Collaboration
Ekko van IerlandWageningen University
based on joint work with Michael Finus, University of Hagen, Rob Dellink, Hans-Peter Weikard, Wageningen University and members of the STACO team
by
Need for sustainable development Globe exists for about 5-7 billion years
Human interaction with the environment needs to continue in a sustainable manner for several billions of years
Sustainable development: non-declining per capita welfare
Required: well balanced stocks of capital Human made capital (Savings and investment; new technologies) Natural capital (Efficient use of natural resources; new technologies) Human capital (Education! Education! inventions)
Brundtland report; Mäler; Pearce; …..
Global problems: Climate change For global problems no legal entities exist that can
enforce: we need voluntary international environmental agreements
How to reach agreement??Which countries will participate?How much emission reduction in each country?How to establish stable international coalition, e.g. Post-
Kyoto protocol?“It is not in our national interest to join the Kyoto protocol”
Barrett, Carraro, Finus, Ulph, Nordhaus, Dellink, Weikard, ..
Structure of the presentation 1. Introduction
2. Collaboration in Cartel formation Game
3. Empirical context
4. Analysis & Results: without and with transfers; renegotiations
5. Conclusions
Some warning at the start: Highly stylized analysis Reality differs from model analysis Setting of standard cost benefits analysis;discount rate 3% Focus on mitigation, not adaptation Impossible to explain all details in about 20 minutes; full
documentation in papers: See: www.enr.wur.nl/STACO
But…. valuable insights can be gained!
2. Cartel Formation Game for Climate
Protocol Coalition formation for 12 regions of the world non-cooperative approach: voluntary agreement cartel formation: one coalition and singletons test for internal and external stability of coalition
Pay-off
Pay-off DiscountingBenefits Abatement costs
Tt
i i it t it itt 1
(1 r ) (B (q ) AC (q ))
q is emission reduction of greenhouse gases
Theoretical background (cont.)1. Regions/countries indicate yes or no for a coalition2. Regions/countries choose abatement strategies: playing Nash against each other and the coalition Signatories maximize sum of pay-offs of coalition members;Signatories maximize sum of pay-offs of coalition members;
Singletons maximize their own pay offSingletons maximize their own pay off All consider the strategies of the other playersAll consider the strategies of the other players
Theoretical background (cont.) Testing for stability of coalition
Internal stability: no country wants to leave the coalition
External stability: no singleton wants to join the coalition
We test stability for 4084 possible coalitions; in case of multiple coalitions 4 million!
3. Empirical Modeling of global
warming Total stock of greenhouse gases in atmosphere according to Nordhaus’ DICE model
Total benefits
3 21 13 243.1 i i i i i iTAC q q q
( ) 1385.1 i i DTB q s q
t
t 2010 t s
t 2011 t pre ind 2010 pre ind s ss 2011
M q ,...,q M 1 M M 1 e q
Total abatement costs
Benefits per region : base caseRegion (i) Share in global benefits
si
1 USA 22.6 2 Japan 17.3 3 EU 23.6 4 Other OECD 3.5 5 Eastern Europe 1.3 6 Former Soviet Union 6.8 7 Energy Exporting countries 3.0 8 China 6.2 9 India 5.0 10 Dynamic Asian economies 2.5 11 Brazil 1.5 12 Rest of the World 6.8
Marginal abatement costs
0
500
1000
1500
2000
2500
3000
0 20 40 60 80 100 120 140 160 180 200 220 240
Q (Gton)
dis
co
un
ted
MA
C (
bln
$/G
ton
= $
/to
n)
Max. 132 Gton at 4564 $/ton
BRA
JPN
OOE
EET
DAE
EEX
EEC
FSU
ROW
IND
USA
CHN
EU
Source: Ellerman and Decaux (1998)
Schematic representation of emission
reduction
2010 2110Time
Em
issi
ons
(Gto
ns o
f C
O2)
Simple setting
Dynamic optimzed setting
4. Analysis & ResultsWe calculate what will happen for all coalitions, but
we report on the following:
Singleton coalition structure: no agreement at all Grand coalition structure: if all would participate! Industrialized countries structure: industrialised
countries No transfers: Stable coalition structure (Japan and
EU), but only if damage are 20% more than in base case.
Transfers by permit trading Renegotiations
Singleton coalition structure (Nash
equilibrium)Regions Average annualemissionreduction
Totalabatement
costs
Benefits minusabatement costs
Marginalabatement costs
percentage ofemissions in
2010
bln US$ over100 years
bln US$ over 100years
US$/ton CO2
USA 6.7 53 415 8.5JPN 1.4 2 354 6.5EU 4.7 24 464 8.8CHN 6.6 16 112 2.3
… … … … …ROW 5.3 4 137 2.5World 4.6 109 1,960 -
Global stock of carbon dioxide by 2110 = 1,561 gton
Grand coalition structureRegions Average annual
emissionreduction
Totalabatement
costs
Benefits minusabatement
costs
Marginalabatement
costs
Incentive to leavecoalition
percentage ofemissions in
2010
bln US$ over100 years
bln US$ over100 years
US$/ ton CO2 bln US$ over 100years
USA 15.7 513 1,656 37.4 23.6JPN 6.5 63 1,590 37.4 -123.8EU 11.5 229 2,033 37.4 -180.1CHN 40.6 1,348 -754 37.4 1133.2
… … … … … …ROW 26.5 250 401 37.4 185.1World 21.4 3,553 6,031 -
Global stock of carbon dioxide by 2110 = 1,475 gton
“Industrialized countries” (as intended)Regions Average annual
emission reduction
Total abatement
costs
Benefits minus abatement
costs
Marginal abatement
costs
Incentive to change
percentage of emissions in
2010
bln US$ over 100 years
bln US$ over 100 years
US$/ ton CO2 bln US$ over 100 years
USA* 13.4 332 574 28.0 65.3
JPN* 5.2 38 653 28.0 -46.9
EU* 9.7 147 798 28.0 -52.8 CHN 6.6 16 232 2.3 -794.9
… … … … … … ROW 5.3 4 268 2.5 -137.8
World 8.9 865 3,140 - -
Global stock of carbon dioxide by 2110 = 1,539 gton Note: * Coalition member
No transfers: Results for stable coalition (EU and
Japan)
Notes: * Coalition member
Level of damages increased in 20%
Regions Average annual emission reduction
Total abatement
costs
Benefits minus abatement
costs
Marginal abatement
costs
Incentive to change
percentage of emissions in
2010
bln US$ over 100 years
bln US$ over 100 years
US$/ ton CO2 bln US$ over 100 years
USA 7.5% 71 606 10.2 -80.1
JPN* 3.6% 17 498 18.3 -18.3
EU* 7.5% 76 629 18.3 -0.1
CHN 7.5% 22 163 2.8 -395.0
… … … … … … ROW 6.0% 5 198 3.1 -69.5
World 5.6% 203 2,784 - -
Global stock of carbon dioxide by 2110 = 1,556 gton
Global emissions reduction (% of base
year)
0
5
10
15
20
25
Singleton Industrializedcountries
Grand coalition Stable coalition(Japan and EU)
av
g.
an
nu
al
em
iss
ion
s r
ed
uc
tio
n (
%)
Damages increased
by 20%
Modify payoff function
Introducing transfers in the coalition: Permit
trading
* * * * *i i i i i i(q ,q ) (q ,q ) p (q q )
Emission permits* *
i i i i ii c i c i c
e e e e
BAU *i i i i
i c
q e e
thus
Initial allocation of permits (pragmatic
criteria)Scenario Operational rule
1) Quota BAUGrandfathering:proportion of emissions2010
2) Quota NashGrandfathering:proportion of emissions inNash equilibrium
Initial allocation of permits (equitable
criteria)Scenario Operational rule
3) Equal sharing Equal allocation
4) Egalitarian Allocation in proportion topopulation
5) Historicalresponsibility
Allocation in inverseproportion to emissions 2010
Initial allocation of permits (equitable
criteria)Scenario Operational rule
6) Ability to pay Allocation in inverseproportion to GDP per capita
7) Ability to pollute Allocation in inverseproportion to emissions percapita
8) Energy efficiency Allocation in inverseproportion to emissions perunit of GDP
Coalition EU-15 and CHN*
* This coalition is internally and externally stable under permit trading-quota BAU scenario. (1) ICM: Incentive to change membership.
Regions Totalemissionreduction
Payoffs(withoutpermittrading )
Payoffs(withpermittrading)
Transfers ICM(1)
(with permittrading)
gton (over100 years)
bln US$over 100years
bln US$over 100years
bln US$over 100years
bln US$over 100years
*iq iq i i
USA 16 - 683 683 - -132.6Japan 1 - 559 559 - -25.0EU-15 8 20 733 595 137 -131.3China 46 34 -6 131 -137 -19.3--- --- --- --- --- --- ---ROW 4 - 217 217 - -24.1World 87 - 2,942 2,942 - -
Permit Price = MACic =11 US$/ton
Coalition EU-15 and CHN*
* This coalition is internally and externally stable under permit trading-quota BAU scenario. (1) ICM: Incentive to change membership.
Regions Total emission reduction
Payoffs (without permit
trading )
Payoffs (with
permit trading)
Transfers ICM(1) (with
permit trading)
gton (over 100 years)
bln US$ over 100
years
bln US$ over 100
years
bln US$ over 100
years
bln US$ over 100
years *
iq iq i i
USA 16 - 683 683 - -132.6 Japan 1 - 559 559 - -25.0 EU-15 8 20 733 595 137 -131.3 China 46 34 -6 131 -137 -19.3 --- --- --- --- --- --- --- ROW 4 - 217 217 - -24.1 World 87 - 2,942 2,942 - -
Permit Price = MACic =11 US$/ton
Stable coalitions, if transfers are used
0
1000
2000
3000
4000
5000
6000
7000
Singleton coalition EU-15,China India, ROW EU-15, EE, India Japan, India Grand coaliton
Glo
bal
ben
efi
ts (
bil
lio
n U
S $
)
Renegotiations
What will happen if renegotiations occur? For instance after 50 years… Or every 20 years …..
Which coalitions will be stable in early commitment periods and in later periods?
Results: more often renegotiations
1st commitment period
2nd commitment period
3rd commitment period
4th comm. period
5th comm. period
Total payoff
USA/EET/FSU/EEX/CHN/DAE/ROW EU-15/EEX/CHN EU-15/EET/CHN USA/CHN USA/CHN 8824
USA/OOE/EET/FSU/CHN/DAE/ROW EU-15/EEX/CHN EU-15/EET/CHN USA/CHN USA/CHN 8801
USA/EET/FSU/EEX/CHN/DAE/ROW EU-15/EET/CHN EU-15/EET/CHN USA/CHN USA/CHN 8785
EU-15/OOE/EET/EEX/CHN/IND/ROW USA/EET/CHN EU-15/EET/CHN USA/CHN USA/CHN 8758
EU-15/EET/EEX/CHN/IND/DAE/ROW USA/EET/CHN EU-15/EET/CHN USA/CHN USA/CHN 8755
EU-15/OOE/EET/FSU/EEX/CHN/IND USA/EET/CHN EU-15/EET/CHN USA/CHN USA/CHN 8754
EU-15/EET/FSU/EEX/CHN/IND/DAE USA/EET/CHN EU-15/EET/CHN USA/CHN USA/CHN 8751
EU-15/OOE/EET/CHN/IND/DAE/ROW USA/EET/CHN EU-15/EET/CHN USA/CHN USA/CHN 8731
EU-15/OOE/EET/FSU/CHN/IND/DAE USA/EET/CHN EU-15/EET/CHN USA/CHN USA/CHN 8727
USA/OOE/EET/EEX/CHN/DAE/ROW EU-15/EEX/CHN EU-15/EET/CHN USA/CHN USA/CHN 8718
{1542 RPE sequences in total}
An optimal transfer scheme Optimal transfer scheme: any scheme that fully uses the
gains from cooperation to enhance stability
Based on surplus sharing not some exogenous rule, such as emissions (as above) the surplus is shared according to “outside option payoffs”,
i.e. how much a region would get if it were to deviate
Maximises internal stability if coalitional surplus exceeds outside option payoffs,
internal stability is guaranteed external stability of course not guaranteed
Renegotiations and an optimal transfer
scheme Renegotiations after 50 years (50 + 50 years) Optimal transfers generate multiple equilibria (626) in
second stage, and large number (35671) of stable coalitions in 1st stage
Best performing: USA, EU-15, EET, EEX, CHN, IND in first stage and EU-15, EET, EEX, CHN, IND in second stage (providing 57% of potential gains from cooperation)
Renegotiations after 20 years (20 + 80 years) Best performing: Grand coalition (!) in first stage and
EU-15, EET, EEX, CHN, IND in second stage (59% of potential gains)
Conclusions (I of IV) How to reach
agreement? Highly stylized model; it assists in explaining international
negotiations: strong free rider incentives!; but gains from cooperation can be large!
Empirical analysis for non-symmetric regions without transfers provides only 1 internally and externally stable coalition: EU and Japan at 1.2 time benchmark damages
“Industrialised countries” reduce 8.9%; Singletons 4.8%; EU-Japan 5.6%, as compared to 2010 level.
Grand coalition in our setting would reduce emissions by 21%, but restricted time horizon and low damages.
Conclusions (II of IV) How to reach agreement? In cartel setting without transfers, coalition formation will
be very difficult in practice, because free rider incentives dominate!
With transfers, and no renegotiations, only a few small coalitions are stable and they reach relatively little as compared to the singleton case.
Conclusions (III of IV) How to reach
agreement? With renegotiations, larger coalitions can be stable, even
the grand coalition in the first period. Substantial results can be reached.
If countries only act on the basis of self-interest not all gains can be obtained
Responsible governments should go for a grand coalition and will share benefits on equity principles.
This requires willingness to cooperate and to accept sanctions if free riding would occur.
Conclusions (IV of IV) How to reach
agreement? Further climate related catastrophes, unless in international
politics adequate policy measures are agreed upon. In Grand coalition global welfare is optimized: we need to
search for such arrangement with USA and others If a grand coalition is impossible, multiple coalitions can be
helpful, as long as all major players make a substantial contribution.
Special note: Climate change will be irreversible and very harmful: no scope for discounting future damages!
Without international cooperation on climate change no sustainable development.
STACO PROJECT
http://www.enr.wur.nl
Environmental Economics and Natural Resources Group
Wageningen University
Thanks!
Free Rider Incentive IndexRegion Free rider incentive index1 USA 4.7%2 Japan 2.6%3 EU 3.3%4 Other OECD 32.4%5 Eastern Europe 100.0%6 Former Soviet Union 19.7%7 Energy Exporting countries 23.7%8 China 45.0%9 India 45.4%10 Dynamic Asian economies 71.2%11 Brazil 23.4%12 Rest of the World 27.0%
Sensitivity analysis for calibration IScenario Benchmarks Total
emissionreduction
Average annualemissionreduction
Totalabatement
costs
Total benefitsfrom
abatement
Benefits minusabatement
costs
gton (over100 years)
percentage ofemissions in
2010
bln US$over 100
years
bln US$ over100 years
bln US$ over100 years
no cooperation 34 2.9 36 644 608benefits 50 % coalition JPN, EU - - - - -
full cooperation 172 14.4 1,225 3,211 1,986
no cooperation 55 4.6 109 2,069 1,960benefits 100 % coalition JPN, EU - - - - -
full cooperation 256 21.4 3,553 9,584 6,031
no cooperation 62 5.2 145 2,801 2,655benefits 120 % coalition JPN, EU 67 5.6 203 2,988 2,784
full cooperation 284 23.8 4693 12,746 8,053
Sensitivity analysis for calibration I
(cont.)Scenario Benchmarks Totalemissionreduction
Average annualemissionreduction
Totalabatement
costs
Total benefitsfrom
abatement
Benefits minusabatement
costs
gton (over100 years)
percentage ofemissions in
2010
bln US$over 100
years
bln US$ over100 years
bln US$ over100 years
no cooperation 62 5.2 145 2,801 2,655benefits 120 % coalition JPN, EU 67 5.6 203 2,988 2,784
full cooperation 284 23.8 4693 12,746 8,053
no cooperation 87 7.3 324 6,485 6,161benefits 200 % coalition JPN, EU 92 7.7 455 6,908 6,453
full cooperation 377 31.5 10,204 28,205 18,000
no cooperation 112 9.3 609 12,519 11,910benefits 300 % coalition JPN, EU 119 9.9 857 13,323 12,466
full cooperation 470 39.3 18,856 52,759 33,903
Future research Test for open and exclusive membership Test for transfer schemes Test for multiple coalition structures
e.g. {1,1,2,2,3,3,3,} Analyze technology spillover Anlyze impacts if lobby groups Test for uncertainty on parameter values Allow for more periods Test for multiple deviations Improve regional damage estimates!
Advantage of model: simplicity of specification allows for huge number of coalition structures to be calculated