John Hassler

Institute for International Economic Studies
Stockholm University


NBER Working Papers and Publications

October 2012Energy-Saving Technical Change
with Per Krusell, Conny Olovsson: w18456
We estimate an aggregate production function with constant elasticity of substitution between energy and a capital/labor composite using U.S. data. The implied measure of energy-saving technical change appears to respond strongly to the oil-price shocks in the 1970s and has a negative medium-run correlation with capital/labor-saving technical change. Our findings are suggestive of a model of directed technical change, with low short-run substitutability between energy and capital/labor but significant substitutability over longer periods through technical change. We construct such a model, calibrate it based on the historical data, and use it to discuss possibilities for the future.
January 2012Economics and Climate Change: Integrated Assessment in a Multi-Region World
with Per Krusell: w17757
This paper develops a model that integrates the climate and the global economy---an integrated assessment model---with which different policy scenarios can be analyzed and compared. The model is a dynamic stochastic general-equilibrium setup with a continuum of regions. Thus, it is a full stochastic general-equilibrium version of RICE, Nordhaus's pioneering multi-region integrated assessment model. Like RICE, our model features traded fossil fuel but otherwise has no markets across regions---there is no insurance nor any intertemporal trade across them. The extreme form of market incompleteness is not fully realistic but arguably not a decent approximation of reality. Its major advantage is that, along with a set of reasonable assumptions on preferences, technology, and nature, it allows a...

Published: John Hassler & Per Krusell, 2012. "Economics And Climate Change: Integrated Assessment In A Multi-Region World," Journal of the European Economic Association, European Economic Association, vol. 10(5), pages 974-1000, October. citation courtesy of

August 2011Optimal Taxes on Fossil Fuel in General Equilibrium
with Mikhail Golosov, Per Krusell, Aleh Tsyvinski: w17348
We analyze a dynamic stochastic general-equilibrium (DSGE) model with an externality through climate change from using fossil energy. A central result of our paper is an analytical derivation of a simple formula for the marginal externality damage of emissions. This formula, which holds under quite plausible assumptions, reveals that the damage is proportional to current GDP, with the proportion depending only on three factors: (i) discounting, (ii) the expected damage elasticity (how many percent of the output flow is lost from an extra unit of carbon in the atmosphere), and (iii) the structure of carbon depreciation in the atmosphere. Very importantly, future values of output, consumption, and the atmospheric CO2 concentration, as well as the paths of technology and population, and so on...

Published: Mikhail Golosov & John Hassler & Per Krusell & Aleh Tsyvinski, 2014. "Optimal Taxes on Fossil Fuel in General Equilibrium," Econometrica, Econometric Society, vol. 82(1), pages 41-88, 01. citation courtesy of

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