Abstract: This paper studies the design of a carbon tax when environmental factors, such as air carbon-dioxide emissions (CO2), directly affect agents’ marginal utility of consumption. Our first result is that the optimal tax is determined by the shadow price of CO2 emissions. We then use asset-pricing theory to estimate this implicit price in the data and find that the optimal tax is pro-cyclical. It is therefore optimal to use the carbon tax to “cool down” the economy during booms and stimulate it in recessions. The optimal policy not only generates large welfare gains, it also reduces risk premiums and raises the average risk-free real rate. The effect of the tax on asset prices and welfare critically depends on the emission-abatement technology.
ECB WP Slides

Abstract: We explore the role of public subsidies in mitigating the transition costs associated with achieving a climate-neutral objective by 2060. To this end, we develop and estimate a quantitative macro-climate model for the world economy featuring an endogenous market structure for carbon abatement products. Public subsidies, fully financed by a carbon tax, are found to be an efficient instrument to promote firm entry into the abatement good sector by fostering competition and lowering the selling price of such products. We estimate that the subsidy, optimally distributed between startups at 60\% and existing companies at 40%, would save nearly $ 2.9 trillion in world GDP each year by 2060. Finally, delaying the net-zero transition would imply giving an even larger share to startups.
SSRN Paper Banque de France WP Online Appendix Slides

Abstract: The paper investigates the dynamic effects of weather shocks on monthly agricultural production in Peru with local projections. An adverse weather shock, measured by an excess of heat or rain, always generates a negative downturn in agricultural production, but its magnitude and duration depend on several factors such as the type of crop concerned, the land geographical type and the season. On average, a weather shock can cause a monthly decline by 5% of agricultural production up to four consecutive months. The response is time and space dependent. A shock in tropical forest regions or occurring during growing season exhibits a much larger response. At a macroeconomic level, weather shocks entail a surge in inflation and reduction in aggregate production. Paper

Abstract: This paper investigates the role of heterogeneous elasticities of substitution in the US production network in the transmission of idiosyncratic shocks. We develop and estimate a multi-industry general equilibrium model featuring heterogeneous elasticities of substitution in input demands. Using quarterly data on 14 US industries, we provide evidence of a relatively large dispersion in input-substitution elasticities across US industries that are generally larger than those previously found in the literature. This dispersion is quantitatively important as substitution heterogeneity accounts for 6% of the total supply shock transmission in the US, and peak to 80% for inter-industry propagation.
Paper

Abstract:Social learning (SL) is a behavioral model in which expectations and the resulting aggregate dynamics stem from the interactions of a large amount of heterogeneous agents. Nonetheless, this framework has so far lacked micro-foundations and a general-solution method. This paper bridges these two gaps with: (i) a micro-founded New Keynesian model with social learning expectations; (ii) a general solution method that we implement in a Dynare toolbox that solves any linear state-space model with SL expectations. The resulting framework provides a self-contained tool to contrast policy analysis under SL and rational expectations. As an illustration, optimal monetary policy rules are studied under the two expectation regimes.
Paper

Abstract:This paper develops and estimates a non-linear New Keynesian Climate (NKC)
model for the world economy featuring climate change damage and mitigation policy. The
model boils down to four equations: Phillips and IS curves, as well as a monetary policy
rule and a law of motion for CO2 emissions. This framework allows us to identify two phenomenons
faced by the central bank. The first one is a persistent negative supply shock called
climateflation that arises from the deleterious effects of climate change itself. The second one is a
transitory positive demand shock called greenflation that appears following the implementation
of a climate mitigation policy.
Slides

Abstract: We study the general equilibrium effects of carbon permit banking during the transition to a climate-neutral economy by 2050. To this end, we develop and estimate an environmental real business cycle model for the European Union, in which the business sector is regulated by an emission trading system. Firms are allowed to transfer unused permits from one period to the next (banking), but the reverse direction (borrowing) is prohibited. Allowing for positive banking gives firms the opportunity to act as speculators and enables them to smooth their permit demand along the business cycle. Our projection exercises underscore the critical role of permit banking in shaping the policy outcomes. Specifically, the 2023 cap reform would lead to a strong increase in permit banking until 2035, a doubling of the carbon price, and an average GDP loss of approximately 5.3% or 6% (depending on whether we account for the market stability reserve) by 2060. Importantly, forgetting about permit banking when assessing cap policies would lead to both a significant underestimation of the total macroeconomic effects and an inaccurate representation of the carbon emission trajectory.
Paper

Abstract: The first contribution of this paper is to develop a model that jointly accounts for the missing disinflation in the wake of the Great Recession and the subsequently observed inflation-less
recovery. The key mechanism works through heterogeneous expectations that may durably lose their anchorage to the central bank (CB)’s target and coordinate on particularly persistent below-target paths. We jointly estimate the structural and the learning parameters of the model by matching moments from both macroeconomic and Survey of Professional Forecasters data. The welfare cost associated with those dynamics may be reduced if the CB communicates to the agents its target or its own inflation forecasts, as communication helps anchor expectations at the target. However, the CB may lose its credibility whenever its announcements become decoupled from actual inflation, for instance in the face of large and unexpected shocks.
SSRN Paper Bank of Canada Working Paper Slides Online Appendix

Abstract: This paper studies the design of Ramsey optimal monetary policy in a Health New Keynesian (HeNK) model with Susceptible, Infected and Recovered (SIR) agents. The nonlinear model is estimated with maximum likelihood techniques on Euro Area data. Our objective is to deconstruct the mechanism by which contagion risk affects the conduct of monetary policy. If monetary policy is the only game in town, we find that optimal policy features significant deviations from price stability to mitigate the effect of the pandemic. The best outcome is obtained when the optimal Ramsey policy is combined with a lockdown strategy of medium intensity. In this case, monetary policy can concentrate on its price stabilization objective. Paper Dynare codes Slides

Abstract: How much do weather shocks matter? The literature addresses this question in two isolated ways: either by looking at long-term effects through the prism of calibrated theoretical models, or by focusing on both short and long terms through the lens of empirical models. We propose a framework that reconciles these two approaches by taking the theory to the data in two complementary ways. We first document the propagation mechanism of a weather shock using a Vector Auto-Regressive model on New Zealand Data. To explain the mechanism, we build and estimate a general equilibrium model with a weather-dependent agricultural sector to investigate the weather’s business cycle implications. We find that weather shocks: (i) explain about 35% of GDP and agricultural output fluctuations in New Zealand; (ii) entail a welfare cost of 0.30% of permanent consumption; (iii) critically increases the macroeconomic volatility under climate change, resulting in a higher welfare cost peaking to 0.46% in the worst case scenario of climate change.
pdf file   online appendix dynare 4.5 code
dynare 4.6+ code

Abstract: This paper questions the role of cross-border lending in the definition of national macroprudential policies in the European Monetary Union. We build and estimate a two-country DSGE model with corporate and interbank cross-border loans, Core-Periphery diverging financial cycles and a national implementation of coordinated macroprudential measures based on Countercyclical Capital Buffers. We get three main results. First, targeting a national credit-to-GDP ratio should be favored to federal averages as this rule induces better stabilizing performances in front of important divergences in credit cycles between core and peripheral countries. Second, policies reacting to the evolution of national credit supply should be favored as the transmission channel of macroprudential policy directly impacts the marginal cost of loan production and, by so, financial intermediaries. Third, the interest of lifting up macroprudential policymaking to the supra-national level remains questionable for admissible value of international lending between Eurozone countries. Indeed, national capital buffers reacting to the union-wide loan-to-GDP ratio only lead to the same stabilization results than the one obtained under the national reaction if cross-border lending reaches 45%. However, even if cross-border linkages are high enough to justify the implementation of a federal adjusted solution, the reaction to national lending conditions remains remarkably optimal.
pdf Appendix dynare code

Abstract: In an estimated DSGE model of the European Monetary Union that accounts for financial differences between core and peripheral countries, we find that country-adjusted macroprudential measures lead to significant welfare gains with respect to a uniform macroprudential policy rule that reacts to union-wide financial developments. However, peripheral countries are the winners from the implementation of macroprudential measures while core countries incur welfare losses, thus questioning the interest of adopting coordinated macroprudential measures with peripheral countries.
pdf file dynare file Data

Abstract: This paper evaluates the role of financial intermediaries, such as banks, in the extensive margin of activity. We build a DSGE model that combines the endogenous determination of the number of firms operating on the goods market with financial frictions through a financial accelerator mechanism. We more particularly account for the fact that the creation of a new activity partly requires loans to finance spendings during the setting period. This model is estimated on US data between 1993Q1 and 2012Q3. We get three main results. First, financial frictions play a key role in determining the number of new firms. Second, in contrast with real macroeconomic shocks (where investment in existing production lines and the creation of new firms move in the opposite direction), financial shocks have a cumulative effect on the two margins of activity, amplifying macroeconomic fluctuations. Third, the critical role of financial factors is mainly observed in the period corresponding to the creation of new firms. In the long run, the variance of the effective entry share is almost explained by supply shocks.
pdf file dynare file data

Abstract: This paper seeks to evaluate quantitatively how interbank and corporate cross-border flows shape business cycles in a monetary union. Using Bayesian techniques, we estimate a two-country DSGE model that distinguishes between Eurozone core and peripheral countries and accounts for national heterogeneities and a set of real, nominal and financial frictions. We find evidence of the key role of this cross-border channel as an amplifying mechanism in the diffusion of asymmetric shocks. Our model also reveals that under banking globalization, most national variables and the central bank interest rate are less sensitive to financial shocks while investment and current account imbalances are more sensitive to financial shocks. Finally, a counterfactual analysis shows that cross-border lending has affected the transmission of the recent financial crisis between the two groups of countries.
pdf dynare file Technical Appendix

Abstract: The authors provide a static two-country new Keynesian model to teach two related questions in international macroeconomics: the international transmission of unilateral monetary policy decisions and the gains coming from the coordination monetary rules. They concentrate on “normal times” and use a thoroughly graphical approach to analyze the questions at hand. In this setting monetary policy is conducted using interest rates rules and economic integration between nations does not necessarily create the case for the coordination of monetary policy. In particular, they show that the conduct of optimal national monetary policies does not make any difference with the coordination of national policies, as this creates a situation where the international monetary system operates “Near an International Cooperative Equilibrium” (NICE).

Abstract: This paper aims at providing a self contained presentation of the ideas and solution procedure of New Keynesian Macroeconomics models. Using the benchmark “3 equation model”, we introduce the reader to an intuitive, static version of the model before incorporating more technical aspects associated with the dynamic nature of the model. We then discuss the relative contribution of supply, demand and policy shocks to the fluctuations of activity, inflation and interest rate, depending on the key underlying parameters of the economy.
dynare file

Abstract: This article introduces macroprudential policy using a static New Keynesian Macroeconomics model with financial frictions. The authors analyze two related questions: First, they show how the procyclicality of financial factors, captured by the financial accelerator, amplifies the transmission of supply and demand shocks and impacts the intuition they get from a basic intermediate macroeconomics. Second, adopting an optimal policy perspective, they show how a policymaker may use macroprudential policy to complete monetary policy measures. Following the Mundellian Policy Assignment principle, macroprudential policy should be specialized to address the procyclicality problem to suppress welfare losses associated with the building of financial imbalances, thus helping monetary policy to concentrate on the output inflation tradeoff.
pdf file