A. Monograph

  • Clemens, M. (2015): Ölpreise und Makroökonomische Stabilisierung in offenen Volkswirtschaften, Springer-Verlag.[Springer-Link]
  • Abstract
    Anhand eines dynamischen stochastischen Gleichgewichtsmodells (DSGE) wird der Zusammenhang zwischen Ölpreisveränderungen und makroökonomischer Stabilität in ölimportierenden Volkswirtschaften analysiert. Vor dem Hintergrund endogener Ölpreise, einer globalen Güter- und Kapitalmarktintegration und einer veränderten Ölmarktstruktur ergeben sich alternative Erklärungsansätze mit neuen Implikationen für die Zentralbankpolitik. Demnach führen Ölpreisschocks eher zur Rezession, wenn Öl nicht substituierbar, internationaler Handel beschränkt oder der geldpolitische Zielkonflikt groß ist. Im Anschluss an die Analyse der Wirkungskanäle werden die optimale Stabilisierungspolitik und das strategische Verhalten der Zentralbank infolge von Ölpreisveränderungen untersucht.

    B. Articles

  • Clemens, M., Schumacher, D. (2012): The Competitiveness of Manufacturing in Euro Countries – The German Perspective -, Journal of Industrial and Business Economics, 39(2):55-76.
  • Abstract
    The aim of the paper is to analyse the performance and characteristics of the manufacturing sector in Germany as compared to Italy and against the background of the Euro countries as a whole. We explore the factor en-dowment and compare specialisation patterns in production and foreign trade with respect to three aggregated industries: resource-intensive, labour-intensive and knowledge-intensive products. The analysis will suggest that the strong position of German industry is mainly based on its technological strength and supported by increasing price competitiveness vis-a-vis other countries in the Euro area.
  • Clemens, M., Mölders, F. (2011): Quo vadis? Deutsche forschungsintensive Exporte auf dem richtigen Weg, Quarterly Journal of Economic Research, DIW Berlin, 80(3):73-88.
  • Abstract
    This article examines the impact of the financial crisis on changes in the sectoral and geographic specialization of Germany’s trade in research-intensive industries. In the first part of this article we calculate and analyze indicators of sectoral specialization for Germany, the US, Japan and the BRIC countries for the period from 2000 to 2010. While German exports in R&D-intensive industries have declined during the crisis, Germany has not fallen behind in terms of export shares on the world market, as opposed to the US and Japan. The impact of the economic turmoil of the past years did not only affect the sectoral level but also the geographic orientation of Germany’s exports and its competitors. In the second part, we therefore additionally calculate an indicator that refers to the geographic concentration of exports. It is shown that German exports in R&D-intensive industries are shifting towards Emerging Markets. Should this trend continue, the growth of the German R&D-intensive exports will depend increasingly on these economies. Against the background of the continued economic growth in the BRIC countries and as drivers of the world economy, their increasing demand may have a sustainable positive effect on the R&D-intensive industry in Germany.
  • Clemens, M., Czernomoriez, J., Fuhrmann, W.(2010): Nachhaltige Ersparnis, Rohstoffe und Humankapital in der Republik Aserbaidschan, Jahrbuch für Aserbaidschanforschung, 3:55-79.
  • Abstract
    Intergenerational justice is a target for policy makers with regard to a sustainable economic growth path in resource abundant countries. This study analyzes the sustainable economic growth path in the Republic of Azerbaijan via the concept of genuine savings. We find that intertemporal substitution of oil welath is mainly well managed and diversified by investments in alternative industries. But particularly tertiary education may be a lack of future development.

    C. Working paper and conference contribution

  • Clemens, M., Claveres, G. (2017): Unemployment Insurance Union, 2017 Meeting Papers 1340, Society for Economic Dynamics.
  • Abstract
    A European unemployment insurance scheme has gained increased attention as a new and ambitious common fiscal instrument which could be used for temporary cross-country transfers. Part of the national stabilizers composing unemployment insurance schemes would be transferred to the central level. Unemployed are then insured by both layers. When a country is hit by an asymmetric shock, it would receive positive net transfers from the central fund in the form of reduced taxes and increased benefits, providing risk-sharing for the whole union. We build a two-country DSGE model with supply, demand and labor market shocks in order to capture the recent national insurance system and the unemployment insurance union (UIU) design. The model is calibrated to the euro area core and periphery data and matches the empirically observed cyclicality of the net replacement rate, the wage and unemployment dynamics. This baseline scenario is then compared to a optimal unemployment insurance union with passive and active benefit policies. For all underlying shocks, we find that the UIU reduces the fluctuation of consumption and unemployment while it increases the fluctuation of the trade balance. In case of a positive domestic government spending shock the UIU reduces the negative crowding out effect on private consumption and investment. The model will be used to analyze the effects of national and supranational benefit policies on labour market patterns and welfare.
  • Clemens, M. (2016): Oil Prices, Terms of Trade and Optimal Monetary Policy, Paper presented at the RES Annual Conference 2016, University of Sussex, Brighton.
  • Abstract
    Recent studies show that considering external channels, i.e. exports, imports, terms of trade, is necessary to explain the observed changing pattern between oil prices and macroeconomic activity. We derive the optimal monetary policy for oil-importing countries under a given oil supply in a three-country DSGE model and explicitly analyze these channels. We found that the terms of trade channel and monetary policy with a terms of trade target can dampen the effect of oil price fluctuations in oil-importing economies depending on structural parameters. We then extend the basic model by assuming different degrees of international central bank cooperation. With respect to the optimal monetary policy reaction on demand and supply-driven oil price changes we derive three noteworthy results. First, central banks of oil importers minimize the welfare loss of real oil price changes by influencing the terms of trade and stabilizing the producer price inflation rate. Second, central banks are able to fully stabilize global and local demand-driven oil price changes depending on the relative size of the countries and the strategic behavior between central banks. Third, welfare losses resulting from global oil supply disruptions can be minimized by a cooperative central bank that stabilizes a weighted consumer price inflation rate and a weighted output gap. A cooperative monetary policy cannot minimize the welfare losses from local oil supply changes.
  • Clemens, M., Hart, J. (2016): Migration, Unemployment and the Business Cycle - A Euro Area Perspective -, Paper presented at the Jahrestagung des Vereins für Socialpolitik.
  • Abstract
    In the recent European debt crisis, internal migration flows in the euro area reacted strongly to diverging labor market conditions. This experience points towards the prominent role of short-term business cycle migration in the euro area and the consequent need to understand the motives behind it. Investigating the business cycle in 55 bilateral migration corridors in the euro area over the period 1980-2010, we find evidence for business cycle related fluctuations in net migration flows and the crucial role of unemployment in shaping migration patterns. While on average wage and unemployment differentials are negatively correlated with net migration, across migration corridors we document a considerable heterogeneity in both dimensions that is more pronounced for wages. In line with these findings, we built a two-country dynamic stochastic general equilibrium (DSGE) model of internal business cycle migration in the euro area and allow for unemployment that occurs as a consequence of labor market frictions and rigidities in both countries. Our model is able to replicate the empirical observations and explains the heterogeneity of migration corridors by differences in the type of shock that hits an economy and the relative price/wage rigidity. We contribute to the literature on the causes and consequences of temporary migration and bridge it to DSGE models with unemployment.
  • Belitz, H., Clemens, M., Von Hirschhausen, C., Schmidt-Ehmke, J., Werwatz, A., Zloczysti, P. (2011): An Indicator for National Systems of Innovation – Methodology and Application to 17 Industrialized Countries, DIW Discussion Paper 1129, Berlin.
  • Arrighetti, A., Ninni, A., Breda, E., Cappariello, R., Clemens, M., Schumacher, D. (2012): Competitiveness in manufacturing. Germany vs. Italy – a comparison, Economics Department Working Papers 2012-EP01, Department of Economics, Parma.
  • Clemens, M., Schumacher, D. (2011): The Technological Competitiveness of the German Economy Revisited, Paper presented at the 9th International Conference on Multinational Enterprise, Chinese Culture University, Taipei.
  • Clemens, M., Czernomoriez, J., Fuhrmann, W. (2010): Rohstoffreichtum und Humankapitalakkumulation in Aserbaidschan, in: Transformation der Wirtschaft und Wissenschaft in Aserbaidschan, Ahad, R., Zurek, E. (eds.), Proceedings of the German-Azerbaijan symposium, University of Bonn.
  • De La Motte, L., Czernomoriez, J., Clemens, M. (2010): Zur Vertrauensökonomik: Der Interbankenmarkt in der Krise 2007-2009, Institute of Macroeconomics, University of Potsdam, Potsdam.
  • Fuhrmann, W., Clemens, M. (2010): Zu einer Währungsunion: Die Staaten des Golf-Kooperationsrates, in: Eine Golf-Währungsunion, El-Ali, K., Clemens, M., Fuhrmann, W., 7-24, Institute of Macroeconomics, University of Potsdam, Potsdam.
  • Clemens, M., Fuhrmann, W. (2008): Rohstoffbasierte Staatsfonds – Theorie und Empirie, Institute of Macroeconomics, University of Potsdam, Potsdam.
  • Clemens, M. (2007): Azerbaijan – Resource Curse and Foreign Direct Investment, International Working Paper, W. Fuhrmann (eds.), Department of Economics, University of Potsdam 2007, Potsdam.
  • D. Policy paper

  • Clemens, M. (2019): Öffentliche Finanzen: Haushaltsspielräume verflüchtigen sich nach und nach – Investitionsprogramm wäre sinnvoll”, DIW Wochenbericht 50 / 2019, S. 952-960.
  • Abstract
    Die derzeit hohen Überschüsse in den öffentlichen Haushalten werden bis 2021 nahezu aufgebraucht sein. Dies liegt nicht nur an der schwächeren konjunkturellen Entwicklung – auch eine expansive Finanzpolitik trägt dazu bei: Im Jahr 2020 fallen vor allem die steuerlichen Entlastungen und nochmaligen Kinder-gelderhöhungen ins Gewicht, ein Jahr darauf dann insbeson-dere die weitgehende Abschaffung des Solidaritätszuschlags sowie die geplante Einführung der Grundrente. Auch die Aus-gaben steigen überdurchschnittlich, unter anderem im Rah-men des Klimaschutzgesetzes. Wenn defizitäre Entwicklungen im Bundeshaushalt und den Sozialkassen in der mittleren Frist bis 2024 vermieden werden sollen, dürften angesichts des bis dahin mehr und mehr zu Buche schlagenden demogra-fischen Wandels nicht nur Beitragssatzerhöhungen bei den Sozialversicherungen erforderlich sein. Zu befürchten ist, dass staatliche Investitionen in Sach- und Humankapital deutlich reduziert werden. Dabei wäre ein Investitionsprogramm gleich doppelt lohnend: Würde der Staat in den nächsten sechs Jah-ren fünf Milliarden Euro pro Jahr zusätzlich in verschiedene Bedarfe investieren und anschließend verstetigen, stiege das Potentialwachstum bereits in der mittleren Frist um 0,3 Pro-zentpunkte. Zudem würden bereits bis 2024 über höhere Ein-nahmen aus Steuern und Sozialbeiträgen knapp 20 Milliarden Euro in die Staatskasse zurückfließen.
  • Sebastian Dullien, S., Kooths, S., Clemens, M., Michelsen, C., Südekum, J., Kolev, G., Walwe, U. (2019): Konjunkturpolitik in der Krise, in: Wirtschaftsdienst, Springer, German National Library of Economics, vol. 99(11), pages 747-768, November 2019.
  • Abstract
    Das Bruttoinlandsprodukt wird 2019 voraussichtlich nur um ein halbes Prozent wachsen. Unter Unsicherheiten leidet vor allem die Industrie wegen der globalen Handelskonflikte und des Brexits. Ob dies in einen gravierenden Abschwung münden wird, darüber gibt es Zweifel. Eine wachstumsorientierte Politik, die den anstehenden Herausforderungen in Hinblick auf Klima-,Energie- und Verkehrswende gerecht wird, scheint hingegen konsensfähig zu sein. Dafür sind steigende öffentliche und private Investitionen unabdingbar. Unterschiedliche Auffassungen gibt es allerdings darüber, inwieweit dies mit Defiziten im Staatshaushalt verbunden werden sollte.
  • Clemens, M., Goerge, M., Michelsen, C. (2019): Public Investment a Key Prerequisite for Private Sector Activity”, DIW Weekly Report 31, pp. 255-261.
  • Abstract
    Ten years after the 2008 financial crisis, in the euro area investment is still below the pre-crisis level. Public and private investment growth is so weak that capital per worker (capital intensity) has virtually remained constant. An increase in public investment activity could ultimately stimulate private investment. Estimates for the euro area show that an increase in public investment by one billion euro goes hand in hand with a medium-term increase in private investment of around 1.1 billion euro. In Germany, the effect is somewhat greater. Investment in construction and infrastructure are the most significant drivers. The public sector’s widespread reluctance to invest could partially explain the weakness in private investment activity. The public sector should now begin investing more. And the rigid balanced budget amendment (Schuldenbremse) should be replaced by more flexible expenditure rules.
  • Clemens, M., Hart, J. (2018): EU immigration has increased Germany’s economic growth”, DIW Weekly Report 44, pp. 441-449.
  • Abstract
    Immigration to Germany has increased significantly since 2011, primarily due to the immigration of citizens from other euro area countries and those which joined the EU in 2004 and 2007. This increase is mainly attributable to a lack of immigration barriers and the good economic situation on the German labor market compared to other European countries. Model simulations show that GDP growth in Germany between 2011 and 2016 would have been 0.2 percentage points lower on average per year without EU immigration. However, structural barriers to immigration remain. Additionally, due to economic recovery and demographic changes in other EU countries, migration from the EU may not continue as strongly as before. It is therefore important to strengthen immigration incentives, such as by giving immigrants more opportunities to find employment matching their skills. In addition to EU immigration, the German economy may also benefit from facilitating access to the labor market for skilled workers from third countries.
  • Bremus, M., Clemens, M., Fratzscher, M., Hammerschmid, A., Kliatskova, T., Kriwoluzky, A., Michelsen, C., Rowold, C., Weinhardt, F., Wrohlich, K. (2019): A Stable and Social Europe: Fiscal Rules, a Stabilization Fund, Insolvency Rules, Gender Quota, Gender Pension Gaps, and Education: Reports”, DIW Weekly Report 16/17/18, pp. 148-159.
  • Clemens, M., Klein, M. (2018): A Stabilization Fund Can Make the Euro Area More Crisis-Proof”, DIW Weekly Report, vol. 8(22/23), pages 193-200.
  • Clemens, M., Gebauer, S., Rieth, M. (2017): Early Exit from ECB Bond Purchase Program Could Reduce GDP Growth and Inflation”, DIW Economic Bulletin, vol. 7(49), pages 533-540.
  • Brenke, K., Clemens, M. (2017): Increased Labor Market Participation Can’t Do the Job of Mastering Germany’s Demographic Change in the Future”, DIW Economic Bulletin, vol. 7(33/34/35), pages 325-334.
  • Albig, H., Clemens, M., Fichtner, F., Gebauer, S., Junker, S., Kholodilin, K. (2017): How rising income inequality influenced economic growth in Germany”, DIW Economic Bulletin.
  • Clemens, M., Mölders, F., Schumacher, D. (2011): Exports – Orientation towards Future Markets”, DIW Economic Bulletin, 1(2):11-15.
  • Clemens, M., Schumacher, D. (2010): Germany Is Well Positioned for International Trade with Research-Intensive Goods, DIW Weekly Report, 11:79-85.
  • Belitz, H., Clemens, M., Gornig, M. (2009): Germany’s Technological Specialization Assures Growth Opportunities, DIW Weekly Report, 16(5):109-112.
  • Belitz, H.; Clemens, M.; Gornig, M.; Mölders, F.; Schiersch, A.; Schumacher, D. (2011): Die deutsche forschungsintensive Industrie in der Finanz- und Wirtschaftskrise im internationalen Vergleich, DIW Berlin, Studien zum deutschen Innovationssystem Nr. 4-2011, Expertenkommission für Forschung und Innovation (eds.), Berlin.
  • Belitz, H., Clemens, M., Gornig, M., Schiersch, A., Schumacher, D. (2010): Wirtschaftsstrukturen, Produktivität und Außenhandel im internationalen Vergleich, DIW Berlin, Studien zum deutschen Innovationssystem Nr. 5-2010, Expertenkommission für Forschung und Innovation (eds.), Berlin.
  • Von Hirschhausen, C.; Belitz, H., Clemens, M., Cullmann, A., Schmidt-Ehmcke, J., Zloczysti; P. (2009): Innovationsindikator Deutschland 2009, DIW Berlin: Politikberatung kompakt, 51.
  • Von Hirschhausen, C., Belitz, H., Clemens, M., Cullmann, A., Schmidt-Ehmcke, J. Triebe, D., Zloczysti, P. (2009): Innovationsindikator 2009: Deutschland hat Aufholbedarf, DIW Wochenbericht, 76(44):756-763.
  • Belitz, H., Clemens, M.., Gornig, M. (2009): Wirtschaftsstrukturen und Produktivität im internationalen Vergleich, DIW Berlin, Studien zum deutschen Innovationssystem Nr. 2-2009, Expertenkommission für Forschung und Innovation (eds.), Berlin, 2009.
  • Belitz, H. Clemens, M., Gornig, M. (2008): Wissensintensive Branchen: Deutschland überholt bei der Wertschöpfung die USA, DIW Wochenbericht, 75(18):233-237.
  • Werwatz, A., Belitz, H., Clemens, M., Schmidt-Ehmke, J., Schneider, S. ,Zloczysti, P. (2008): Innovationsindikator Deutschland – Bericht 2008, DIW Berlin: Politikberatung kompakt, 45.
  • Belitz, H., Clemens, M., Schmidt-Ehmke, J., Schneider, S., Werwatz, A. (2008): Deficits in Education Endanger Germany´s Innovative Capacity, DIW Weekly Report, 4(14):86-93.
  • Werwatz, A., Belitz, H., Clemens, M., Kirn, T., Schmidt-Ehmke, J., Schneider, S. (2007): Innovationsindikator Deutschland – Bericht 2007, DIW Berlin: Politikberatung kompakt, 33.