SABIIA - Sistema Aberto e Integrado de Informação em Agricultura (Sabiia)

A constant social discount rate cannot reflect both a reasonable opportunity cost of public funds and an ethically defensible concern for generations in the distant future. We use a model of hyperbolic discounting that achieves both goals. We imbed this discounting model in a simple climate change model to calculate constant equivalent discount rates" and plausible levels of expenditure to control climate change. We compare these results to discounting assumptions and policy recommendations in the Stern Review on Climate Change.

Time perspective and climate change policy

Palavras-chave: Discounting; Climate change modeling; Stern Review; Markov Perfect Equilibria; Environmental Economics and Policy; C61; C73; D63; D99; Q54.

Ano: 2007

URL: http://purl.umn.edu/7149

The tendency to foreshorten time units as we peer further into the future provides an explanation for hyperbolic discounting at an intergenerational time scale. We study implications of hyperbolic discounting for climate change policy, when the probability of a climate-induced catastrophe depends on the stock of greenhouse gasses. We provide a positive analysis by characterizing the set of Markov perfect equilibria (MPE) of the intergenerational game amongst a succession of policymakers. Each policymaker reflects her generation’s preferences, including its hyperbolic discounting. For a binary action game, we compare the MPE set to a “restricted commitment” benchmark. We compare the associated “constant equivalent discount rates” and the willingness to pay...

CLIMATE POLICY WHEN THE DISTANT FUTURE MATTERS: CATASTROPHIC EVENTS WITH HYPERBOLIC DISCOUNTING

Palavras-chave: Hyperbolic discounting; Markov Perfect Equilibria; Catastrophic climate change; Uncertainty; Environmental Economics and Policy; Resource /Energy Economics and Policy; C61; C73; D63; D99; Q54.

Ano: 2008

URL: http://purl.umn.edu/42848

Low probability catastrophic climate change can have a signifcant influence on policy under hyperbolic discounting. We compare the set of Markov Perfect Equilibria (MPE) to the optimal policy under time-consistent commitment. For some initial levels of risk there are multiple MPE; these may involve either excessive or insufficient stabilization effort. These results imply that even if the free-rider problem amongst contemporaneous decision-makers were solved, there may remain a coordination problem amongst successive generations of decision-makers. A numerical example shows that under plausible conditions society should respond vigorously to the threat of climate change.

Sacrifice, discounting and climate policy: five questions

Palavras-chave: Abrupt climate change; Event uncertainty; Catastrophic risk; Hyperbolic discounting; Markov Perfect Equilibria; Environmental Economics and Policy; C61; C73; D63; D99; Q54.

Ano: 2007

URL: http://purl.umn.edu/7181

Karp, Larry S..

I provide a selective review of discounting and climate policy. After reviewing evidence on the importance of the discount rate in setting policy, I ask whether standard models tend to exaggerate the sacrifices that the current generation needs to undertake in order to internalize climate damages. I then consider whether the risk of catastrophic damage really overwhelms discounting, in the determination of optimal policy. I revisit the question of how we actually think about the distant future.

Climate Policy When the Distant Future Matters: Catastrophic Events with Hyperbolic Discounting

Palavras-chave: Climate change; Discounting; Intergenerational conflict; Catastrophic risk; Hyperbolic discounting; Environmental Economics and Policy; Research Methods/ Statistical Methods; Resource /Energy Economics and Policy; C61; C73; D63; D99; Q54.

Ano: 2009

URL: http://purl.umn.edu/51612

Low probability catastrophic climate change can have a significant influence on policy under hyperbolic discounting. We compare the set of Markov Perfect Equilibria (MPE) to the optimal policy under time-consistent commitment. For some initial levels of risk there are multiple MPE; these may involve either excessive or insufficient stabilization effort. These results imply that even if the free-rider problem amongst contemporaneous decision-makers were solved, there may remain a coordination problem amongst successive generations of decision-makers. A numerical example shows that under plausible conditions society should respond vigorously to the threat of climate change.

Is the Just Man a Happy Man? An Empirical Study of the Relationship Between Ethics and Subjective Well-Being

Palavras-chave: Abrupt climate change; Event uncertainty; Catastrophic risk; Hyperbolic discounting; Markov Perfect Equilibria; Environmental Economics and Policy; Risk and Uncertainty; C61; C73; D63; D99; Q54.

Ano: 2007

URL: http://purl.umn.edu/7186

Harvey, James S., Jr..

In this paper I consider the question of whether ethical decision-making affects a person’s happiness. Using cross-country data from the World Values Survey, I find that people who agree that it is never justifiable to engage in ethically-questionable behaviors report that they are more satisfied with their life than people who are more tolerant of unethical conduct, even after controlling for other factors known to affect self-reported happiness. The size of the ethics effect is roughly similar to that of a modest increase in income, being married and attending church, while the effect is smaller than that of having poor health or being dissatisfied with one’s personal finances. These results are robust across the four countries studied (the US, Canada,...