Tag: game theory

After two weeks of negotiations between the 195 countries attending the COP21 climate change conference in Paris, a deal has been reached on tackling climate change. Although the deal still has to be ratified by countries, this is a major step forward in limiting global warming. Before it can formally come into force, it must have been ratified by at least 55 countries, accounting for at least 55% of global greenhouse gas emissions.

The deal goes much further than previous agreements and includes the following:

  A limit on the increase in global temperatures to ‘well below’ 2°C above pre-industrial levels and efforts pursued to limit it to 1.5°C.
A recognition that the pledges already made ahead of the conference by 186 countries and incorporated into the agreement are insufficient and will only limit global temperature rise to 2.7°C at best.
Countries to update their emissions reductions commitments every five years – the first being in 2020. Such revised commitments should then be legally binding.
A global ‘stocktake’ in 2023, and every five years thereafter, to monitor countries’ progress in meeting their commitments and to encourage them to make deeper cuts in emissions to reach the 1.5°C goal. This requires a process of measurement and verification of countries’ emissions.
To reach a peak in greenhouse gas emissions as soon as possible and then to begin reducing them and to achieve a balance between sources and sinks of greenhouse gases (i.e. zero net emissions) in the second half of this century.
Developed countries to provide the poorest developing countries with $100bn per year by 2020 to help them reduce emissions. This was agreed in Copenhagen, but will now be continued from 2020 to 2025, and by 2025 a new goal above $100bn per year will be agreed.
The development of market mechanisms that would award tradable credits for green projects and emissions reductions.
A recognition that the ‘loss and damage’ associated with climate-related disasters can be serious for many vulnerable developing countries (such as low-lying island states) and that this may require compensation. However, there is no legal liability on developed countries to provide such compensation.

Perhaps the major achievement at the conference was a universal recognition that the problem of global warming is serious and that action needs to be taken. Mutual self interest was the driving force in reaching the agreement, and although it is less binding on countries than many would have liked, it does mark a significant step forward in tackling climate change.

But why did the conference not go further? Why, if there was general agreement that global warming should be tackled and that global temperature rise should ideally be capped at 1.5°C, was there not a binding agreement on each country to apply this cap?

There are two reasons.

First, it is very difficult to predict the exact relationship, including its timing, between emissions and global temperature rise. Even if you could make limits to emissions binding, you could not make global temperature rise binding.

Second, even if there is general agreement about how much emissions should be reduced, there is no general agreement on the distribution of these reductions. Many countries want to do less themselves and others to do more. More specifically, poor countries want rich countries to do all the cutting while many continue to build more coal-fired power stations to provide the electricity to power economic development. The rich countries want the developing countries, especially the larger ones, such as China, India and Brazil to reduce their emissions, or at least the growth in their emissions.

Then there is the difference between what countries vaguely pledge at a global conference and what they actually do domestically. Many developed countries are keen to take advantage of currently cheap fossil fuels to power economic growth. They are also still investing in alternative sources of fossil fuels, such as through fracking.

As we said in the previous blog, game theory can shed some useful insights into the nature and outcome of climate negotiations. ‘The global optimum may be for a strong agreement, binding on all countries. The Nash equilibrium, however, may be a situation where countries push for their own interests at the expense of others, with the final agreement being much more minimalistic.’

‘Minimalistic’ may be too strong a description of the outcomes of the Paris conference. But they could have been stronger. Nevertheless, judged by the outcomes of previous climate conferences, the deal could still be described as ‘historic’.

Videos

With landmark climate accord, world marks turn from fossil fuels Reuters (13/12/15)
COP21 climate change summit reaches deal in Paris BBC News (13/12/15)
COP21: Paris climate deal is ‘best chance to save planet’ BBC News (13/12/15)
COP21: Climate change deal’s winners and losers BBC News, Matt McGrath (13/12/15)
The Five Key Decisions Made in the UN Climate Deal in Paris Bloomberg, video: Nathaniel Bullard; article: Ewa Krukowska and Alex Morales (12/12/15)
The key factors in getting a deal in Paris BBC News on YouTube, Tom Burke (13/12/15)

Articles

COP21 agreement: All you need to know about Paris climate change deal Hindustan Times, Chetan Chauhan (13/12/15)
COP21: Paris agreement formally adopted Financial Times, Pilita Clark and Michael Stothard (12/12/15)
Let’s hail the Paris climate change agreement and get to work Financial Times, Jeffrey Sachs (12/12/15)
COP21: Public-private collaboration key to climate targets Financial Times, Nicholas Stern (13/12/15)
Paris climate change agreement: the deal at a glance The Telegraph, Emily Gosden (12/12/15)
Climate Accord Is a Healing Step, if Not a Cure New York Times, Justin Gillis (12/12/15)
Paris Agreement Ushers in End of the Fossil Fuel Era Slate, Eric Holthaus (12/12/15)
Paris Agreement: the reaction Business Green, James Murray and Jessica Shankleman (12/12/15)
World’s First Global Deal to Combat Climate Change Adopted in Paris Scientific American, David Biello (12/12/15)
COP21: Paris climate deal ‘our best chance to save the planet’, says Obama Independent, Tom Bawden (13/12/15)
Grand promises of Paris climate deal undermined by squalid retrenchments The Guardian, George Monbiot (12/12/15)
Paris Agreement on climate change: the good, the bad, and the ugly The Conversation, Henrik Selin and Adil Najam (14/12/15)
COP21: James Hansen, the father of climate change awareness, claims Paris agreement is a ‘fraud’ Independent, Caroline Mortimer (14/12/15)
Paris climate agreement: More hot air won’t save us from oblivion Sydney Morning Herald, Peter Hartcher (15/12/15)

Draft Agreement

Adoption of the Paris Agreement United Nations Framework Convention on Climate Change (12/12/15)

Questions

  1. Could the market ever lead to a reduction in greenhouse gas emissions? Explain.
  2. What are the main strengths and weaknesses of the Paris agreement?
  3. Is it in rich countries’ interests to help poorer countries to achieve reductions in greenhouse gas emissions?
  4. How might countries reduce the production of fossil fuels? Are they likely to want to do this? Explain.
  5. Is a ‘cap and trade’ (tradable permits) system (a) an effective means of reducing emissions; (b) an efficient system?
  6. What is the best way of financing investment in renewable energy?

The Paris Climate Change Conference (COP21) is under way. At the opening on November 30, 150 Heads of State gathered in Paris, most of whom addressed the conference. With representatives from 195 countries and observers from a range of organisations, the conference is set to last until 11 December. Optimism is relatively high that a legally binding and universal agreement will be reached, with the aim of keeping global warming below 2°C – what is generally regarded as a ‘safe’ limit.

But although it is hoped that a successor to the Kyoto Protocol of 1997 will be put in place, there are many problems in getting so many countries to agree. They may all wish to reduce global warming, but there is disagreement on how it should be achieved and how the burden should be shared between countries.

There are several difficult economic issues in the negotiations. The first is the size and impact of the external costs of emissions. When a country burns fossil fuels, the benefits are almost entirely confined to residents of that county. However, the environmental costs are largely external to that country and only a relatively small fraction is borne by that country and hardly at all by the polluters themselves, unless there is a carbon tax or other form or penalty in place. The problem is that the atmosphere is a common resource and without collective action – national or international – it will be overused.

The second problem is one of distribution. Politicians may agree in principle that a solution is necessary which is equitable between nations, but there is considerable disagreement on what is meant by ‘equitable’ in this context. As the third Guardian article below puts it:

The most important hurdle could be over whether industrialised countries like the US, UK and Japan, which have contributed the most to the historical build-up of emissions, should be obliged to cut more than developing countries. India, on behalf of many poor countries, will argue that there must be “differentiation” between rich and poor; but the US wants targets that are applicable to all. A collision is inevitable.

A third problem is that of uncertainty. Although there is general agreement among scientists that human action is contributing to global warming, there is less agreement on the precise magnitude of the causal relationships. There is also uncertainty over the likely effects of specific emissions reductions. This uncertainty can then be used by governments which are unwilling to commit too much to emissions reductions.

A fourth difficulty arises from the intertemporal distribution of costs and benefits of emissions reductions. The costs are born immediately action is taken. Carbon taxes or charges, or subsidies to renewables, or caps on emissions, all involve higher energy prices and/or higher taxes. The flows of benefits (or lower costs), however, of reduced emissions are not likely to be fully experienced for a very long time. But governments, whether democratic or dictatorships, tend to have a relatively short time horizon, governed by the electoral cycle or the likelihood of staying in power. True, governments may not be solely concerned with power and many politicians may have genuine desires to tackle climate change, but their political survival is still likely to be a major determinant of their actions.

Of course, if there is strong public opinion in favour of action to reduce emissions, governments are likely to respond to this. Indeed, all the expressions of public support for action ahead of the conference from all around the world, do give some hope for a strong agreement at the Paris conference. Nevertheless, there is still widespread scepticism in many countries over the relationship between human action and climate change, and many argue that the costs of policies to tackle climate change exceed the benefits.

Game theory can shed some insights into the difficulties ahead for the negotiators. The global optimum may be for a strong agreement, binding on all countries. The Nash equilibrium, however, may be a situation where countries push for their own interests at the expense of others, with the final agreement being much more minimalistic.

There do, however, seem to be more reasons to be cheerful at this summit that at previous ones. But negotiations are likely to be hard and protracted over the coming days.

Videos and webcasts
Paris Climate Conference: The Big Picture Wall Street Journal on YouTube, Jason Bellini (30/11/15)
Why is the Paris UN climate summit important? PwC, Leo Johnson (14/10/15)
Paris climate change summit 2015: ‘the near impossible task’ Channel 4 News on YouTube, Tom Clarke (30/11/15)
COP21: Rallies mark start of Paris climate summit BBC News, David Shukman (29/11/15)
With climate at ‘breaking point’, leaders urge breakthrough in Paris Reuters, Bruce Wallace and Alister Doyle (1/12/15)
COP21: Paris conference could be climate turning point, says Obama BBC News (30/11/15)
Leaders meet to reach new agreement on climate change BBC News, David Shukman (30/11/15)
Poll: Growing Doubts Over Climate Change Causes Sky News, Thomas Moore (30/11/15)
Paris climate protesters banned but 10,000 shoes remain The Guardian (29/11/15)

Articles

COP-21 climate deal in Paris spells end of the fossil era The Telegraph, Ambrose Evans-Pritchard (29/11/15)
Is there an economic case for tackling climate change? BBC News, Andrew Walker (28/11/15)
World Leaders in Paris Vow to Overcome Divisions on Climate Change Wall Street Journal, William Horobin and William Mauldin (30/11/15)
Experts discuss how to build a carbon-free energy industry The Guardian, Tim Smedley (25/11/15)
Africa could lead world on green energy, says IEA head The Guardian, Anna Leach (11/11/15)
Climate change talks: five reasons to be cheerful or fearful The Guardian, John Vidal (30/11/15)
The Paris climate change summit, explained in 4 charts The Washington Post, Philip Bump (30/11/15)
Why This Goal To Curb Climate Change ‘Is Not Ideal’ Huffington Post, Jacqueline Howard (30/11/15)
Paris climate change talks: What the different groups attending expect from these crucial meetings Independent, Tom Bawden (29/11/15)
UN Climate Change Conference: World Leaders Call For Price On CO2 Emissions Despite Uphill Battle At Paris Summit International Business Times, Maria Gallucci (30/11/15)
World Bank, six nations call for a price on carbon SBS (Australia) (1/12/15)
Uruguay makes dramatic shift to nearly 95% electricity from clean energy The Guardian, Jonathan Watts (3/12/15)

Questions

  1. Why is COP21 considered to be so significant?
  2. For what reasons is there hope for a binding agreement to limit global warming to 2°C?
  3. What would be the effect on global warming of the commitments made by more than 180 countries prior to the conference?
  4. What market failings contribute towards the problem of global warming?
  5. Why, if all countries want to achieve a binding agreement at the Paris conference, is it likely to be so difficult to achieve?
  6. Explain what is meant by a ‘Nash equilibrium’ and how the concept is relevant to international negotiations.
  7. Why is China investing heavily in solar power?
  8. Could Africa lead the world in green energy?
  9. Is a ‘cap and trade’ (tradable permits) system (a) an effective means of reducing emissions; (b) an efficient system?
  10. What is the best way of financing investment in renewable energy?
  11. How does the structure/order of the Paris conference differ from previous COPs? Is such a structure more likely to achieve substantial results?

In December, most of the countries of the world will meet in Paris at the 21st annual United Nations Conference of the Parties (COP) on climate change. COP21 ‘will, for the first time in over 20 years of UN negotiations, aim to achieve a legally binding and universal agreement on climate, with the aim of keeping global warming below 2°C.’

When the Copenhagen conference (COP15) ended in disagreement in 2009, few people thought that the increase in renewable energy would be anything like sufficient to prevent global temperatures rising more than 2°C. But things have dramatically changed in the intervening six years.

Solar power and other renewables have increased dramatically and the technology for the cleaner burning of fossil fuels, including carbon capture and storage, has developed rapidly.

But perhaps the most important change has been the attitudes of governments. No longer is it a case of Europe and other developed countries moving in the direction of renewables, while developing countries, and, in particular, China and India, argue that their economic development requires a rapid expansion of coal-fired power stations. Now China, India and many other emerging countries are rapidly developing their renewable sectors. This is partly driven by the fall in the costs of renewables and partly by worries that climate change will directly effect them. Now the ‘pro-coal’ countries are in a minority.

And industry is realising that significant profit is to be made from the development and installation of power plants using renewable energy. This is driving both R&D and investment. As the Telegraph article, linked below, points out, in 2009 ‘the International Energy Agency (IEA) was still predicting that solar power would struggle to reach 20 gigawatts by now. Few could have foretold that it would in fact explode to 180 gigawatts – over three times Britain’s total power output – as costs plummeted, and that almost half of all new electricity installed in the US in 2013 and 2014 would come from solar’.

So is this a good news story? Will real progress be made at COP21 in Paris? The articles explore the issues.

Articles

Paris climate deal to ignite a $90 trillion energy revolution The Telegraph, Ambrose Evans-Pritchard (28/10/15)
OP21 deal critical for low-carbon economy Japan Times, Carlos Ghosn (29/10/15)
Is Solar Without Subsidies Now Viable? Oilprice.com, Michael McDonald (22/10/15)

Policy Paper
The road to Paris and beyond Centre for Climate Change Economics and Policy, Grantham Research Institute on Climate Change and the Environment (LSE), Rodney Boyd, Fergus Green and Nicholas Stern (August 2015)

Report

Energy and Climate Change International Energy Agency (October 2015)

Questions

  1. What are the drivers for a move from fossil fuels to renewables? Are they similar dirvers in both developed and developing countries?
  2. What externalities are involved in energy production (a) from fossil fuels; (b) from renewables?
  3. What policies can be adopted to internalise the externalities?
  4. What are the merits and problems of a carbon trading scheme? What determines its effectiveness in reducing CO2 emissions?
  5. Why are more and more investors moving into the renewable energy sector? Could this become a speculative bubble? Explain.
  6. How might game theory help to explain the process and outcomes of international negotiations over climate change and energy use?

A professor in the USA recently posed an interesting dilemma to students taking his psychology exam. At the end of the exam students were provided with a bonus question in order to gain extra credit. All they had to do was decided whether they would like two or six additional marks adding on to their final score. The twist was that if more than 10% of the class opted for an additional six marks then everyone would get nothing added on!

The professor had placed the students in a prisoner’s dilemma scenario. To see this consider an individual student weighing up which option to choose; if more than 90% of the class chose two additional marks, then this student is better off choosing six additional marks. Whereas if more than 90% of the class chose six additional marks, then this student is indifferent between the two options (the student will get no additional marks regardless of their choice). It follows that choosing six additional marks is a weakly dominant strategy.

In a similar fashion, in the classic prisoners setting keeping quiet is collectively better, however, each criminal has a strong individual incentive to confess. Likewise, in oligopoly markets the interdependence between firms results in a tension between cooperation and competition. Firms collectively benefit from keeping prices high, but an individual firm has an incentive to undercut its rivals and steal a large share of the market. A strong prediction when self-interested participants play the prisoner’s dilemma game just once and choose their strategies independently is therefore that the prisoners will confess to the crime and that firms will set low prices.

So did the US professor end up giving away many bonus marks? No, about 20% of the class opted for six additional marks and as a result all the students ended up with no extra marks. In fact, the professor claims to have been running the same experiment for the previous seven years and only once has he ended up giving away any bonus marks. On the one hand, this result is consistent with what is predicted in the prisoner’s dilemma game. However, running contrary to this is the fact that around 80% of the students opted for just two additional marks. It would certainly be interesting to see what would happen if in future years the professor relaxed the threshold above which all students get no extra marks.

UMD ‘tragedy of the commons’ tweet goes viral The Baltimore Sun, Quinn Kelley (09/07/15)
A professor tested the ‘Prisoner’s Dilemma’ on his students by bribing them with extra credit points Tech Insider, Will Haskell (17/07/15)

Questions

  1. Draw the payoff matrix for the student’s dilemma.
  2. What are some of the possible explanations for around 80% of the class choosing two extra marks?
  3. How do you think the outcome of the game might have changed if students were allowed to communicate with each other before making their choice on the number of additional marks to ask for?
  4. How do you think student choices would change if the threshold above which all students get no extra marks was varied?

The negotiations between Greece and the ‘troika’ of creditors (the IMF, the European Commission and the ECB) have seen many twists and turns before breaking down on 26 June. Throughout, both sides have sought to give as little as possible while seeking a compromise. Both sides have claimed that their position is reasonable, even though a gulf has remained between them.

What has been playing out is a high-stakes game, where the optimum outcome for each side is quite different.

Greece seeks bailout terms that would allow it to achieve a smaller primary budget surplus (but still a surplus in the midst of a deep recession). The surplus would be achieved largely through tax rises on the wealthy rather than further cuts that would hit the poor hard. It is also seeking a substantial amount of debt forgiveness to make servicing the remaining debt possible.

The troika is seeking a larger budget surplus than the Greeks are willing to contemplate. This, it maintains, should be achieved largely through additional cuts in government expenditure, including further reductions in pensions and in public-sector wages.

Both sides used threats and promises as the negotiations became more and more acrimonious.

The troika threatened to withhold the final €7.2bn of the bailout necessary to pay the €1.6bn due to the IMF on 30 June, unless the Greeks accepted the terms of the austerity package put to them. The Greek Prime Minister, Alexis Tsipras, in rejecting the proposals, called a referendum on the package. This threatens the stability of the eurozone as a No vote, if it led to a Greek exit from the eurozone, could undermine confidence in monetary union. After all, if Greece could be forced out, other countries facing severe difficulties might also be forced out at some point in the future. Once a country leaves the eurozone, the monetary union becomes more like a system of pegged exchange rates. And pegged exchange rates are open to destabilising speculation at times of economic divergence.

A Greek exit from the euro (dubbed ‘Grexit’) is seen as undesirable by most Greeks and by most politicians in the rest of Europe. The optimum for both sides collectively would be a compromise, which saw more modest cuts by Greece and the eurozone remaining intact. By both sides seeking to maximise their own position, the Nash equilibrium is certainly not the best outcome.

But as long as the troika believes that the Greeks are likely to vote Yes to the proposed bailout terms, it still hopes to get the outcome that is best from its point of view – an outcome that would probably involve regime change. And as long as the Greek government hopes that a No vote will force the troika to think again and come back with less austere proposals, it still hopes to get the outcome that is best from its point of view. But the outcome of this game of ‘chicken’ could well be Grexit and a Nash equilibrium that neither side wants.

But while the endgame is being played out by politicians, people in Greece are suffering. Policies of severely depressing aggregate demand to turn a large budget deficit into a primary budget surplus have led to the economy shrinking by 26%, overall unemployment of 27% and youth unemployment of over 60%. The Greeks truly believe themselves to be stuck between a rock and a hard place.

The following articles look at the nature of the ‘game’ being played and at the effects on the Greek economy, both of the proposed austerity package proposed by the troika and Grexit. They also look at the knock-on effects for the eurozone, the EU and the global economy.

Can game theory explain the Greek debt crisis? BBC News Magazine, Marcus Miller (26/6/15)
Against the Grain: What Yanis Varoufakis can learn from a real game theory master – Nicola Sturgeon City A.M., Paul Ormerod (24/6/15)
John Nash’s Game Theory and Greece Bloomberg, Mohamed A. El-Erian (29/5/15)
The Greek crisis: that 1931 moment The Economist, Buttonwood column (23/6/15)
How game theory explains Grexit and may also predict Greek poll outcome The Conversation, Partha Gangopadhyay (1/7/15)
Greece debt crisis: Tsipras may resign if Greeks vote yes BBC News (30/6/15)
Greek debt crisis: Is Grexit inevitable? BBC News. Paul Kirby (29/6/15)
Existential threat to euro from Greek exit BBC News, Robert Peston (29/6/15)
How I would vote in the Greek referendum The Guardian, Joseph Stiglitz (29/6/15)
Greece in chaos: will Syriza’s last desperate gamble pay off? The Guardian, Paul Mason (29/6/15)
What happens if Greece defaults on its International Monetary Fund loans? The Telegraph, Mehreen Khan (30/6/15)
For Greece’s international creditors, regime change is the ultimate goal The Telegraph, Jeremy Warner (29/6/15)
Europe has suffered a reputational catastrophe in Greece The Telegraph, Ambrose Evans-Pritchard (2/7/15)

Questions

  1. What is meant by a primary budget surplus?
  2. What was the troika’s proposal on the table on the 26 June that was rejected by the Greek government?
  3. What was the Greek government’s proposal that was rejected by the troika?
  4. Explain the decision trees outlined in the first BBC article below.
  5. In terms of game theory, what form of game is being played?
  6. Are the negotiations between the Greek government and the troika a prisoners’ dilemma game? Explain why or why not.
  7. Does the game being played between the SNP and the Conservative government in the UK offer any useful lessons to both sides in the negotiations over Greece’s possible bailout and its terms?
  8. Does a No vote in the referendum on 5 July imply that Greece must leave the euro? Explain.
  9. What would be the effects of further austerity measures on aggregate demand? What benefits to the Greek economy could be achieved from such measures?
  10. Why may pegged exchange rates be regarded as the worst of both worlds – a single currency in a monetary union and floating exchange rates?