Sinn’s main areas of research cover the topics of taxes, regulation, the labour market, the environment, growth and exhaustible resources, foreign trade, banks, insurance and risk, climate and energy, demography and social insurance, macro-economics, system competition and system transformation. His research results have been published in the American Economic Review, the Journal of Public Economics and Quarterly Journal of Economics.
At the beginning of his academic career Sinn primarily focused on the economic theory of risk. His doctoral thesis submitted in 1977 and published by Mohr Siebeck in 1980 as Ökonomische Entscheidungen bei Ungewissheit (Sinn 1980a) was also published in English as Economic Decisions under Uncertainty (Sinn 1983a) by North Holland in 1983. The main focus of this work lies on the symbiosis of expected utility theory and the axiomatic basis of the mean-variance analysis, the Principle of Insufficient Reason, the psychological foundation of risk preferences, and above all, the explanation of an excessive inclination to take risks thanks to limited liability and wealth at the expense of third parties. This theory later became a central element of the explanation for the behaviour of zombie banks. According to Martin Hellwig (2008), Sinn anticipated a central aspect of the Stiglitz and Weiss article published in 1981, which is the standard reference work. Sinn’s doctoral thesis gave rise to an article in the Quarterly Journal of Economics on the principle of insufficient reason (Sinn 1980b), an article in the European Economic Review on decisions under risk with limited liability (Sinn 1982a) and an article on the psychology of risk-taking decisions in the Journal of Economic Psychology (Sinn 1985a).
With his article published in 1980 entitled "Besteuerung, Wachstum und Ressourcenabbau. Ein allgemeines Gleichgewichtsmodell” (Sinn 1980c) Sinn was the first economist to formulate an intertemporal general equilibrium in a decentrally organised, growing economy that satisfied the main theorems of welfare theory. He thus anticipated relevant work by Abel and Blanchard (1983) and Chamley (1981). With reference to Sinn’s first authorship by the publisher, an English translation of the article was published in the specialist journal the European Economic Review in 1982 (Sinn 1982b). Sinn also used his theory in his habilitation thesis entitled: “Kapitaleinkommensbesteuerung. Eine Analyse der intertemporalen, internationalen und intersektoralen Allokationswirkungen” published in 1985 by Mohr Siebeck (Sinn 1985b). An English translation was published in 1987 by North Holland Publishing Company under the title “Capital Income Taxation and Resource Allocation” (Sinn 1987). His article in the American Economic Review on the negative impact of anticipated increases in the value-added tax rate on growth was also in the tradition of this strand of research (Sinn and Howitt 1989).
Sinn published a larger number of works on the topics of taxation policy, business cycle theory, environmental economics and international trade, including works on the asset approach, as well as on the microfoundation of the theory of temporary equilibrium as part of an IS-LM model, a symbiosis between Keynsian and neo-classical theory (Sinn 1983b).
At an early stage in his career Sinn started to research current economic policy topics and began work on a series of policy monographs written in a way accessible to the general public.
In 1991, together with his wife Gerlinde Sinn, Sinn wrote Kaltstart. Volkswirtschaftliche Aspekte der Deutschen Vereinigung published by Mohr Siebeck (Sinn und Sinn 1991). An English translation of the book was published in 1992 by MIT Press as Jumpstart. The Economic Unification of Germany (Sinn und Sinn 1992). There were several editions of the book in German and English, and it was published in a total of six languages.
Sinn’s criticism of the, in his opinion, excessively risky policy pursued by Germany’s Landesbanken is described in Der Staat im Bankwesen (Sinn 1997). An English version of the book was published in 1999 by Edward Elgar under the title The German State Banks. Global Players in the International Financial Markets (Sinn 1999a). In this book he anticipated the disastrous future development of this category of banks.
With his work on the demographical crisis (Sinn 1999b, 2000), Sinn proved that there is a present value equivalent between a pay-as-you-go system and a funded system. He drew the conclusion that no system is superior to the other. However, the pay-as-you-go system needs to be complemented by partial funding in order to tackle foreseeable demographic problems as of 2030. Sinn was also the leading author of a report by the Scientific Advisory Council of the German Federal Ministry for Economics, which became the blueprint for the Riester pension. Sinn’s Munich University-based institute CES supported the German Federal Ministry of Labour in drafting the law at that time.
In his book The New Systems Competition (Blackwell, Sinn 2003a), based on the Yrjö-Jahnsson Lectures held in Helsinki in 1999, Sinn formulated the Selection Principle, whereby competition between states fundamentally cannot function because states manage the exceptions to the competition process. In one chapter he demonstrates that national systems of banking regulation erode in systems competition and lead banks to take excessive risks when doing business. His arguments triggered a controversy with liberal economists in the journal Finanzarchiv in which Sinn reinforced his calls for an international harmonisation and tightening of banking regulation (Sinn 2003b).
In his book Ist Deutschland noch zu retten? (Econ, Sinn 2003c) Sinn analysed Germany’s role in global location competition, criticised the crippling organisation of the German welfare state and further developed his system of Activating Social Aid formulated in 2002. The essential aspects of this system were taken up by the Scientific Advisory Council of the German Federal Ministry of Economics and by the German Council of Economic Experts and according to Wolfgang Wiegard, a member of the Council of Economic Experts, were used as a blueprint for Chancellor Schröder's Agenda 2010. Twelve editions of the book were published, making it the best-selling academic economic policy book in Germany for a century. An English translation was also published by MIT Press in 2007 under the title Can Germany be Saved? The Malaise of the World’s First Welfare State (Sinn 2007). An article by D. Snower et al. discussing thebook was published in 2009 in the Journal of Economic Literature that highlighted the importance of the book in the analysis of the incentive problems of ageing welfare states (Snower et al. 2009). Endorsements of the Book.
In Die Basarökonomie (Econ, Sinn 2005) Sinn developed the theory of the “pathological export boom”. Thanks to its rigid wage policy, Germany invested too little in domestic sectors, exported too much capital and at the same time channelled too much capital and added value into the capital-intensive, downstream stages of the export industry.
In his book Das grüne Paradoxon: Plädoyer für eine illusionsfreie Klimapolitik (Econ, Sinn 2008a) and in a scientific article published by him ahead of the book (“Public Policies against Global Warming: A Supply Side Approach”, International Tax and Public Finance, Sinn 2008b) Sinn developed a new supply-side approach to climate policy that attempts to explain carbon emissions via the decisions made by the owners of fossil resources. His central argument is that the announcement of replacement technologies is seen by resource owners as a measure that will destroy their market. The resource owners seek to counter this measure by anticipating their extraction of fossil fuels, which, in turn, accelerates climate change instead of slowing it down. A broad new strand of research in climate policy emerged from his work that has since given rise to a host of academic articles on this topic. An English version of Sinn’s book entitled The Green Paradoxon: A Supply Side Approach to Global Warming was published in 2012 by MIT Press (Sinn 2012a). German book testimonials.
In his book published in 2009 entitled Kasino-Kapitalismus. Wie es zur Finanzkrise kam, und was jetzt zu tun ist (Sinn 2009) Sinn blames insufficient banking regulation, and especially an excessively low minimum capital ratio, for the financial crisis of 2007. In this book he draws on his earlier work mentioned above on the topic of banks’ willingness to take risks as being artificially boosted by liability limitations. Sinn also argues in favour of the classical Ordoliberalism as developed by Walter Eucken, Alfred Müller-Armack, Alexander Rüstow and Ludwig Erhard, which gives a strong state the responsibility for embedding competition processes into a state-controlled legal framework. Instead of a self-regulating market economy, Sinn affirms the importance of self-regulation within a framework of rules and institutions defined by the state. An English version of the book entitled Casino Capitalism. How the Financial Crash Came About and What Needs to be Done Now was published in 2010 by Oxford University Press (Sinn 2010). The Handelsblatt selected it as one of the top fifty most important economics books of all time (Handelsblatt 2012). Endorsements of the Book.
In Die Target-Falle – Gefahren für unser Geld und unsere Kinder (Hanser, Sinn 2012b) Sinn analyses the euro crisis as a balance-of-payments crisis by drawing on his previous articles on Target balances. Sinn publicly pointed out the rising Target balances in the crisis as early as February 2011. He interpreted them as a "bail-out with the printing press" by the ECB which came ahead of the official bail-out packages and subsequently forced parliaments to follow with fiscal rescue schemes. With his co-author Timo Wollmershäuser, he generated the first panel data set for the Eurosystem Target balances from the balance sheet of the national central banks and the IMF statistics using a method that was subsequently also adopted by the ECB (“Target Loans, Current Account Balances and Capital Flows: the ECB’s Rescue Facility”, Sinn und Wollmershäuser 2012). Martin Wolf called Sinn’s explanations “brilliant” in the Financial Times (Wolf 2011). Wolfgang Münchau made similar statements in the same newspaper (Münchau 2012). German book testimonials.
Related to the book Die Target Falle is The Euro Trap. On Bursting Bubbles, Budgets, and Beliefs published in July 2014 by the Oxford University Press (Sinn 2014). In this book Sinn argues that the interest conversion exerted by the euro created an inflationary credit bubble in the southern euro countries, robbing them of their competitiveness. Since prices can be pushed up easily, but are much harder to bring down, the countries of southern Europe and France are sitting in a trap. They need to depreciate to regain competitiveness, but cannot do so because they are stuck in the euro. To stabilise the Eurozone, Sinn proposes a flexible euro allowing states to enter and exit. William Nordhaus describes Sinn's book as "brave and brilliant". Kenneth Rogoff calls it, “perhaps the most important scholarly book on the euro in at least a decade." The Euro Trap was selected by the Financial Times as one of the world's best books in economics in 2014. Endorsements of the Book.
In Der Euro: Von der Friedensidee zum Zankapfel (Hanser 2015, Sinn 2015), a revised and updated translation of The Euro Trap, shows Sinn, that the euro was supposed to be more than just a currency from the very beginning: it embodies the desire for unity and peace in Europe. A good decade after its introduction, however, it is causing a deep rift right across Europe. In the South unemployment remains unbearably high and the economy has been brought to its knees. The North, on the other hand, has been forced into the role of paymaster and is being held hostage by the ECB. Dissatisfaction is growing on both sides as a result. We have embarked upon a political path that will endager our market economy, democracy and peace in Europe.
Abel, Andrew B. and Olivier J. Blanchard (1983), “An Intertemporal Model of Saving and Investment”, Econometrica 51, p. 675–692.
Chamley, Christophe (1981), “The Welfare Cost of Capital Income Taxation in a Growing Economy”, Journal of Political Economy 89, p. 468–96.
Handelsblatt (2012), “Die 50 wichtigsten Wirtschaftsbücher aller Zeiten”, 12 October, p. 62.
German Council of Economic Experts (2002), “Zwanzig Punkte für Beschäftigung und Wachstum”, Annual Report 2002/03.
Hellwig, Martin (2008), “Preface”, in: Hans-Werner Sinn, Risk Taking, Limited Liability, and the Banking Crisis. Selected Reprints, Ifo Institute, Munich, p. 1.
Münchau, Wolfgang (2012), “The Bundesbank Has No Right at All to be Baffled”, Financial Times, 5 March, p. 9.
Scientific Advisory Committee of the German Federal Ministry for the Economy and Technology (1998), Grundlegende Reform der gesetzlichen Rentenversicherung, BMWA-Studienreihe 99 (Expert Report), 20/21 February.
Scientific Advisory Committee of the German Federal Ministry for the Economy and Technology (2002), Reform des Sozialstaats für mehr Beschäftigung im Bereich gering qualifizierter Arbeit, Dokumentation 512 (Expert Report), 28/29 June.
Sinn, Hans-Werner (1980a), Ökonomische Entscheidungen bei Ungewißheit, J. C. B. Mohr (Paul Siebeck), Tübingen 1980, 374 pages.
Sinn, Hans-Werner (1980b), “A Rehabilitation of the Principle of Insufficient Reason”, Quarterly Journal of Economics 94, p. 493–506.
Sinn, Hans-Werner (1980c), "Besteuerung, Wachstum und Ressourcenabbau. Ein allgemeiner Gleichgewichtsansatz", in: H. Siebert, ed., Erschöpfbare Ressourcen, Schriften des Vereins für Socialpolitik, Duncker und Humblot, Berlin, p. 499–528.
Sinn, Hans-Werner (1980d), “The Theory of Temporary Equilibrium and the Keynesian Model”, Zeitschrift für Nationalökonomie 40, p. 281–320.
Sinn, Hans-Werner (1982a), “Kinked Utility and the Demand for Human Wealth and Liability Insurance”, European Economic Review 17, p. 149–162.
Sinn, Hans-Werner (1982b), “Taxation, Growth, and Resource Extraction: A General Equilibrium Approach”, European Economic Review 19, p. 357–386.
Sinn, Hans-Werner (1983a), Economic Decisions under Uncertainty, North Holland, Amsterdam, New York und Oxford 1983, 359 pages.
Sinn, Hans-Werner (1983b), "International Capital Movements, Flexible Exchange Rates and the IS-LM Model. A Comparison Between the Portfolio-Balance and the Flow Hypotheses", Weltwirtschaftliches Archiv 119, p. 36–63.
Sinn, Hans-Werner (1985a), “Psychophysical Laws in Risk Theory”, Journal of Economic Psychology 6, p. 185–206.
Sinn, Hans-Werner (1985b), Kapitaleinkommensbesteuerung. Eine Analyse der intertemporalen, internationalen und intersektoralen Allokationswirkungen, J. C. B. Mohr (Paul Siebeck), Tübingen, 352 pages.
Sinn, Hans-Werner (1987), Capital Income Taxation and Resource Allocation, North Holland, Amsterdam, New York, Oxford und Tokio, 411 pages.
Sinn, Hans-Werner (1997), Der Staat im Bankwesen. Zur Rolle der Landesbanken in Deutschland, Beck Verlag, München, 156 pages.
Sinn, Hans-Werner (1999a), The German State Banks. Global Players in the International Financial Markets, Edward Elgar, Aldershot, 140 pages.
Sinn, Hans-Werner (1999b), “Die Krise der Gesetzlichen Rentenversicherung und Wege zu ihrer Lösung”, in: Bavarian Academy of Sciences, Yearbook 1998, Beck Verlag, Munich, p. 96–119.
Sinn, Hans-Werner (2000), “Why a Funded Pension System is Useful and Why It is Not Useful”, International Tax and Public Finance 7, p. 389–410.
Sinn, Hans-Werner (2003a), The New Systems Competition, Yrjö Jahnsson Lectures, Basil Blackwell, Oxford, 228 pages.
Sinn, Hans-Werner (2003b), “Asymmetric Information, Bank Failures, and the Rationale for Harmonizing Banking Regulation. A Rejoinder on Comments of Ernst Baltensperger and Peter Spencer”, Finanzarchiv 59, p. 340–346.
Sinn, Hans-Werner (2003c), Ist Deutschland noch zu retten?, Econ Verlag, Munich, 496 pages.
Sinn, Hans-Werner (2007), Can Germany be Saved? The Malaise of the World’s First Welfare State, MIT Press, Cambridge, Mass., 356 pages.
Sinn, Hans-Werner (2005), Die Basar-Ökonomie. Deutschland: Exportweltmeister oder Schlusslicht?, Econ Verlag, Berlin, 249 pages.
Sinn, Hans-Werner (2008a), Das grüne Paradoxon – Plädoyer für eine illusionsfreie Klimapolitik, Econ Verlag, Berlin, 480 pages.
Sinn, Hans-Werner (2008b), “Public Policies against Global Warming: A Supply Side Approach”, International Tax and Public Finance 15, p. 360–394.
Sinn, Hans-Werner (2009), Kasino-Kapitalismus: Wie es zur Finanzkrise kam, und was jetzt zu tun ist, Econ Verlag, Berlin, 352 pages.
Sinn, Hans-Werner (2010), Casino Capitalism. How the Financial Crisis Came About and What Needs to be Done Now, Oxford University Press, Oxford 2010, 400 pages.
Sinn, Hans-Werner (2012a), The Green Paradox, MIT Press, Cambridge, Mass., 288 pages.
Sinn, Hans-Werner (2012b), Die Target Falle – Gefahren für unser Geld und unsere Kinder, Hanser, Munich, 418 pages.
Sinn, Hans-Werner (2014), The Euro Trap. On Bursting Bubbles, Budgets, and Beliefs, Oxford University Press, Oxford, 416 pages.
Sinn, Hans-Werner (2015), Der Euro: Von der Friedensidee zum Zankapfel (The Euro: From Peace Project to Bone of Contention), Hanser: Munich, October 2015, 480 pages. (Revised and updated translation of The Euro Trap).
Sinn, Hans-Werner and Peter Howitt (1989), “Gradual Reforms of Capital Income Taxation”, American Economic Review 79, p. 106–124.
Sinn, Hans-Werner and Gerlinde Sinn (1991), Kaltstart. Volkswirtschaftliche Aspekte der Deutschen Vereinigung, J.C.B. Mohr (Paul Siebeck), Tübingen, 231 pages.
Sinn, Hans-Werner and Gerlinde Sinn (1992), Jumpstart. The Economic Unification of Germany, MIT Press, Cambridge, Mass., und London, England, 238 pages.
Sinn, Hans-Werner and Timo Wollmershäuser (2012), “Target Loans, Current Account Balances and Capital Flows: the ECB’s Rescue Facility”, International Tax and Public Finance 19, p. 468–508; updated version of the CESifo Working Paper 3500, June 2011 and the NBER Working Paper 17626, November 2011.
Snower, Dennis J., Alessio J. G. Brown and Christian Merkl (2009), "Globalization and the Welfare State: A Review of Hans-Werner Sinn's Can Germany Be Saved?", Journal of Economic Literature 47, p. 136–58.
Wolf, Martin (2011), “What Has the ECB Done in the Crisis? The Role of TARGET Balances”, FT Blogs Martin Wolf's Exchange, 28 December.