MC ISAAC Florent

Using the gross world product (GWP) as the only exogenous input variable, we design a model able to accurately reproduce the global population dynamics over the period 1950–2015. For any future increasing GWP scenarios, our model yields very similar population trajectories. The major implication of this result is that both the United Nations and the Intergovernmental Panel on Climate Change assume future decoupling possibilities between economic development and fertility that have never been witnessed during the last sixty-five years. In case of an abrupt collapse of the economic production, our model responds with higher death rates that are more than offset by increasing birth rates, leading to a relatively larger and younger population. Finally, we add to our model an excess mortality function associated with climate change. Estimates of additional climate-related deaths for 2095-2100 range from 1 million in a +2◦C scenario to 6 million in a +4◦C scenario.

Using the gross world product (GWP) as the only exogenous input variable, we design a model able to accurately reproduce the global population dynamics over the period 1950–2015. For any future increasing GWP scenarios, our model yields very similar population trajectories. The major implication of this result is that both the United Nations and the Intergovernmental Panel on Climate Change assume future decoupling possibilities between economic development and fertility that have never been witnessed during the last sixty-five years. In case of an abrupt collapse of the economic production, our model responds with higher death rates that are more than offset by increasing birth rates, leading to a relatively larger and younger population. Finally, we add to our model an excess mortality function associated with climate change. Estimates of additional climate-related deaths for 2095-2100 range from 1 million in a +2◦C scenario to 6 million in a +4◦C scenario.

To what extent can worldwide carbon pricing foster the transition towards a low-carbon economy and mitigate the effects of global warming? We address this question by assessing the financial impacts and macroeconomic implications of carbon pricing and public subsidies. More specifically, we evaluate the extent to which such policies are sustainable by computing the probability of remaining below two thresholds that we argue to be indicative of the stability of our current economy and climate: (1) a temperature anomaly above +2°C (a commonly acknowledged target, including in the 2015 Paris Agreement, to potentially avoid nonlinearities in the climate system) and (2) a large global debt-to-output ratio of 270%.

No summary available.

This paper follows van der Ploeg (Metroeconomica 37(2):221–230, 1985)’s research program in testing both its extension of Goodwin (in: Feinstein (ed) Socialism, capitalism and economic growth, Cambridge University Press, Cambridge, 4, 54–58, 1967) predator–prey model and the Minsky Financial Instability Hypothesis (FIH) proposed by Keen (J Post Keynes Econ 17(4):607–635, 1995). By endowing the production sector with CES technology rather than Leontief, van der Ploeg showed that the possible substitution between capital and labor transforms the close orbit into a stable focus. Furthermore, Keen (1995)’s model relaxed the assumption that profit is equal to investment by introducing a nonlinear investment function. His aim was to incorporate Minsky’s insights concerning the role of debt finance. The primary goal of this paper is to incorporate additional properties, inspired by van der Ploeg’s framework, into Keen’s model. Additionally, we outline possibilities for production technology that could be considered within this research program. Using numerical techniques, we show that our new model keeps the desirable properties of Keen’s model. However, we also demonstrate that when the economy is endowed with a class of CES production function that includes the Cobb–Douglas and the linear technology as limit cases, the unique stable equilibrium is an economically desirable one. Finally, we propose a modified extension that includes speculative component in the economy as in Grasselli and Costa-Lima (Math Financ Econ 6(3):191–210, 2012) and investigate its effect on the dynamics. We conclude that CES production function is a more suitable assumption for empirical purposes than the Leontief counterpart. Finally, we show, using numerical simulations, that under plausible calibration, the model endowed with CES production function eventually lose the cyclical property of Goodwin’s model with and without the speculative component.

No summary available.

No summary available.

Since the stagflation observed following the sharp rise in the price of oil in 1973 and 1979, oil shocks have been considered one of the most potentially important sources of fluctuations in the United States as well as in many industrialized countries. Many articles have studied the role of oil shocks in the fluctuation of the main macroeconomic variables, namely growth, unemployment, inflation and wages. However, this work has not yet led to a consensus. The debate has even intensified over the past decade, due to a lack of a strong response from the real economy during the period of rising oil prices between 2002 and 2007. In effet, the recession that such a price increase should have caused was not observed until the subprime crisis in 2008. Several hypotheses were put forward to explain the difference between the crises of the 1970s and 2000s. Blanchard & Gali (2009) and Blanchard & Riggi (2013) mention, for example, the reduction in the amount of oil used in production, greater flexibility in real wages and greater credibility of monetary policy. Hamilton (2009) and Kilian (2008), on the other hand, suggest that it can be explained by the different origins of the two oil shocks: a supply shock during the 1970s and a demand shock during the 2000s. The original objective of the thesis was to re-examine the impact of oil shocks on the real economy through the debt channel. [The development of this work initiated in the thesis may lead to an alternative modeling framework that is decisive for the intelligence of macroeconomics. It should allow a better understanding of the evaluation of the reciprocal relations between the financial sphere, the reality of real macroeconomic cycles, energy and climate in what is undoubtedly the challenge of our generation: the ecological transition.

Ever since the stagflation that followed the oil price run-ups of 1973 and 1979, oil price shocks have been considered one of the most influential sources of economic fluctuation in the United States and other developed countries. A large body of literature has analyzed oil price shocks as sources of variation for leading macroeconomic variables such as GDP growth, unemployment rate, inflation, and wages. However, scholars have yet to reach a consensus as to the true impact of oil shocks on the macroeconomic environment. Furthermore, the last decade has seen the debate intensify as the results of the relatively (in comparison with the 1970s) muted reaction of the real economy during the 2002-6 oil price run-up. Indeed, the recessionary effect was only observed during the subprime mortgage crisis of 2008-9. Numerous hypotheses have been put forward to explain the difference in impact during the 1970s versus the 2000s. For instance, Blanchard & Gali (2009) and Blanchard & Riggi (2013) evoked the reduction of the quantity of oil used of a unit of production, more flexible real wages, and a better credibility of the monetary policy. Hamilton (2009) and Kilian (2008) pinpointed a difference in the nature of the shock: whereas the oil shocks of the 1970s were driven by supply, that of the 2000s was led by demand. The original aim of this thesis was to reevaluate the impact of the oil shock in the 2000s through the debt channel. First, based on the work of Banchard & Gali, we proposed a new dynamic stochastic general equilibrium model (DSGE), which includes oil as an input of production as well as a consumption good. By relaxing some of the hypotheses of Blanchard & Gali, especially the decoupling of the output elasticity of oil with the cost-share in the production, our work demonstrated that oil is still a fundamental variable of the GDP in the United States. Furthermore, we found that energy efficiency is a key factor that explains the muted macroeconomic impact of an increase in oil prices. A third line of inquiry that may explain the difference between the shocks of the 1970s and the 2000s considers the extra costs implied by a higher price of oil that were absorbed by private debt (which was itself exacerbated by low interest rates set by the Federal Reserve in the 2000s). However, we found that DSGE modeling is unable to replicate the macroeconomic environment that led to the subprime mortgage crisis. In light of these considerations, I reoriented my thesis along the lines of a new angle of research that seeks to represent economic mechanisms differently. Under this new frame-work, private debt is at the core of macroeconomic analysis. It provides an alternative view of the financial crisis that occurred in the 2000s.[.]The conclusions of this thesis demonstrate great potential for providing foundations for new perspectives in macroeconomic modeling. The papers included in the thesis allow, in particular, for a better understanding of situations that most macroeconomic models are not able to cope with, including the over indebtedness crisis. As a result, the framework introduced here may provide an alternative and improved perspective for public policy. Further development of the research presented in this thesis may lead to the improvement of other frameworks in the field of macroeconomics. This would allow for a better understanding of complex interactions between the financial sphere, real business cycles, energy, and climate in what is certainly the biggest challenge of our generation : the ecological shift.

The economic implications of oil price shocks have been extensively studied since the 1970s. Despite this huge literature, no dynamic stochastic general equilibrium model was available that captures two well-known stylized facts: (1) the stagflationary impact of an oil price shock, together with (2) the influence of the energy efficiency of capital on the depth and length of this impact. We build, estimate and simulate a New-Keynesian model with capital accumulation, which takes the case of an economy where oil is imported from abroad, and where these stylized facts can be accounted for. Moreover, the Bayesian estimation of the model on the US economy (1984-2007) suggests that the output elasticity of oil might have been above 10%, stressing the role of oil use in US growth at this time. Finally, our simulations confirm that an increase in energy efficiency significantly attenuates the effects of an oil shock-a possible explanation of why the third oil shock (1999-2008) did not have the same macro-economic impact as the first two ones. These results suggest that oil consumption and energy efficiency have been two major engines for US growth in the last three decades.

The economic implications of oil price shocks have been extensively studied since the 1970s'. Despite this huge literature, no dynamic stochastic general equilibrium model was available that captures two well-known stylized facts: 1) the stagflationary impact of an oil price shock, together with 2) the influence of the energy productivity of capital on the depth and length of this impact. We build, estimate and simulate a New-Keynesian model with capital accumulation, which takes the case of an economy where oil is imported from abroad, and where these stylized facts can be accounted for. Moreover, the Bayesian estimation of the model on the US economy (1984-2007) suggests that the output elasticity of oil might have been above 10%, stressing the role of oil use in US growth at this time. Finally, our simulations confirm that an increase in energy efficiency significantly attenuates the effects of an oil shock —a possible explanation of why the third oil shock (1999-2008) did not have the same macro-economic impact as the first two ones.