the greenhouse effect damages costs and abatement the buildup of so called greenhouse gases in the atmosphere co2 in particular appears to be having an adverse impact on the global climate this paper briefly reviews current expectations with regard to physical and biological effects their potential costs to society and likely costs of abatement for a worst case scenario it is impossible to assess in economic terms the full range of possible non linear synergistic effects in the most favorable although not necessarily likely case of slow paced climate change however it seems likely that the impacts are within the affordable range at least in the industrialized countries of the world in the third world the notion of affordability is of doubtful relevance making the problem of quantitative evaluation almost impossible we tentatively assess the lower limit of quantifiable climate induced damages at 30 to 35 per ton of co2 equivalent worldwide with the major damages being concentrated in regions most adversely affected by sea level rise the non quantifiable environmental damages are also significant and should by no means be disregarded the costs and benefits of 1 reducing cfc use and 2 reducing fossil fuel consumption as a means of abatement are considered in some detail this strategy has remarkably high indirect benefits in terms of reduced air pollution damage and even direct cost savings to consumers the indirect benefits of reduced air pollution and its associated health and environmental effects from fossil fuel combustion in the industrialized countries range from 20 to 60 per ton of co2 eliminated in addition there is good evidence that modest e g 25 reductions in co2 emissions may be achievable by the u s and by implication for other countries by a combination of increased energy efficiency and restructuring that would permit simultaneous direct economic benefits savings to energy consumers of the order of 50 per ton of co2 saved a higher level of overall emissions reduction possibly approaching 50 could probably be achieved at little or not net cost by taking advantage of these savings we suggest the use of taxes on fossil fuel extraction or a carbon tax as a reasonable way of inducing the structural changes that would be required to achieve significant reduction in energy use and co2 emissions to minimize the economic burden and create a political constituency in support of the approach we suggest the substitution of resource based taxes in general for other types of taxes on labor income real estate or trade that are now the main sources of government revenue while it is conceded that it would be difficult to calculate the optimal tax on extractive resources we do not think this is a necessary prerequisite to policy making in fact we note that the existing tax system has never been optimized according to theoretical principles and is far from optimal by any reasonable criteria

discount rates equity weights and the social cost of carbon abstract equity weighting has been proposed as a way of allowing welfare equivalents to be included in the social cost of carbon since a dollar to a poor person is worth more than a dollar to a rich one here we use the page2002 integrated assessment model to show that the social cost of carbon is higher without equity weights an elasticity of marginal utility with respect to income of 0 than with them this might seem counter intuitive but it comes about because of the logical link between equity weights and discount rates as the elasticity goes from 0 to 0 5 to 1 0 the social rate of time preference rises and the drop in present values that results far outweighs the small increase in impacts that equity weights bring

proper risk aversion on introduit et on etudie une condition comportementale significative sur les fonctions d utilite pour les richesses qui signifie qu une loterie indesirable ne peut jamais etre rendue desirable par la presence d une loterie indesirable independante

intergenerational equity and sustainability abstract this paper explores the limitations of conventional economic analysis of intergenerational problems and examines some of the alternatives suggested in the literature it is argued that proper consideration of future generations has at least three requirements first when future costs and benefits are considered it should be taken into account that they are to be enjoyed by different generations second the sustainability requirement should be adopted this represents an equity commitment to the future and implies the recognition that future generations have the right to nondeteriorated ecological and economic capacity the paper studies the ways in which the recognition of these rights might be incorporated into economic evaluation and management third an appropriate institutional network to enforce the recognition of these rights in decision making processes should be constituted its design and necessary functions are also analyzed

are optimal emissions really optimal four critical issues for economists in the greenhouse although the greenhouse effect is by many considered as one of the most serious environmental problems several economic studies of the greenhouse effect most notably nordhaus s dice model suggest that it is optimal to allow the emissions of greenhouse gases ghg to increase by a factor of three over the next century other studies have found that substantial reductions can be justified on economic grounds this paper explores into the reasons for these differences and identifies four partly overlapping crucial issues that have to be dealt with when analysing the economics of the greenhouse effect low probability but catastrophic events cost evaluation methods the choice of discount rate the choice of decision criterion the paper shows that i these aspects are crucial for the policy conclusions drawn from models of the economics of climate change and that ii ethical choices have to be made for each of these issues this fact needs wider recognition since economics is very often perceived as a value neutral tool that can be used to provide policy makers with optimal policies

discounting risk and inequality a general approach the common practice consists in using a unique value of the discount rate for all public investments endorsing a social welfare approach to discounting we show how different public investments should be discounted depending on the risk on the returns on investment the systematic risk on aggregate consumption the distribution of gains and losses and inequality we also study the limit value of the discount rate for very long term investments we highlight the type of information that is needed about long term scenarios in order to evaluate investments

cost benefit assessment of energy efficiency investments accounting for future resources savings and risks in the australian residential sector this article focuses on the impact of the discount rate on cost benefit assessment of investment options for residential building efficiency an integrated thermal modeling life cycle costing approach is applied to an extensive sample of dominant house designs for australian conditions the relative significance of predicted thermal performance and the applied discount rate on the present value of energy savings from alternative investment scenarios is investigated costs and benefits are also evaluated at the economy wide scale including carbon pricing considerations and for a test case household faced with alternative investment options at the point of construction the influence of the applied discount rate on produced cost benefit calculations is investigated as is the interaction between critical cost benefit input parameters findings support that the discounting framework is the primary driver of difference in estimates about costs and benefits of higher standards of efficiency in the residential sector results demonstrate that agreement on a low discount rate based on sustainability principals would prioritise those projects with significant environmental benefits

how much damage will climate change do recent estimates two reasons to be concerned about climate change are its unjust distributional impact and its negative aggregate effect on economic growth and welfare although our knowledge of the impact of climate change is incomplete and uncertain economic valuation is difficult and controversial and the effect of other developments on the impacts of climate change is largely speculative the authors find that poorer countries and people are more vulnerable than are richer countries and people a modest global warming is likely to have a net negative effect on poor countries in hot climates but may have a net positive effect on rich countries in temperate climates if one counts dollars the world aggregate may be positive if one counts people the world aggregate is probably negative negative impacts would become more negative and positive impacts would turn negative for more substantial warming the marginal costs of carbon dioxide emissions are uncertain and sensitive to assumptions that partially reflect ethical positions but are unlikely to be larger than 50 per tonne carbon

discounting in a world of limited growth this paper explores the consequences fordiscounting of assuming limits to growth one of the main determinants of the discount rate is the rate of economic growth if growth rates decline in the future then the discount rate should not be constant but also decline over time in fact we would then need not a single discount rate but rather a variable discount schedule this would imply higher present values for the distant future the paper analyses how discount rates would vary with different assumptions about the patterns of growth and the pure rate of time preference

individual risk attitudes measurement determinants and behavioral consequences this paper studies risk attitudes using a large representative survey and a complementary experiment conducted with a representative subject pool in subjects homes using a question asking people about their willingness to take risks in general we find that gender age height and parental background have an economically significant impact on willingness to take risks the experiment confirms the behavioral validity of this measure using paid lottery choices turning to other questions about risk attitudes in specific contexts we find similar results on the determinants of risk attitudes and also shed light on the deeper question of stability of risk attitudes across contexts we conduct a horse race of the ability of different measures to explain risky behaviors such as holdings stocks occupational choice and smoking the question about risk taking in general generates the best all round predictor of risky behavior

welfare specifications and optimal control of climate change an application of fund the sensitivity of the optimal control of carbon dioxide emissions to the specification of the social welfare function is systematically explored using the fund model increasing risk aversion emphasises climate change damages relative to emission reduction costs but at the same time increases the discount rate of consumption without international co operation the discount rate effect dominates so that optimal control decreases with increasing risk aversion with international co operation optimal control first increases then decreases with increasing risk aversion since climate change falls heaviest on the poor optimal control increases with increasing inequity aversion full fledged intergenerational welfare functions on the one hand emphasise climate change damages but on the other hand place more weight on current poorer generations in fund the two tendencies almost cancel

reconciling sustainability and discounting in cost benefit analysis a methodological proposal abstract the incorporation of the intergenerational equity objective has rendered the traditional cost benefit analysis cba approach obsolete for the evaluation of projects presenting an important number of environmental externalities and for those whose impacts extend throughout a long period of time based on the assumption that applying a discount rate rewards current consumption and therefore that it is only possible to introduce a certain intergenerational equity in a cost benefit analysis in this work we propose an approach to discounting based on a different rationale for tangible and intangible effects we designed two indicators of environmental profitability a the intergenerational transfer amount ita which quantifies in monetary units what the current generation is willing to pass on future generations when an environmental restoration project is carried out and b the critical environmental rate cer measures the implicit environmental profitability these concepts were tested through an empirical case study pertaining to the assessment of an erosion control project in the southeast of spain the results yield traditional profitability indicators that are higher and probably closer to the real values set by the contemporary society the information provided by the environmental profitability indicators proposed renders more transparency to the quantification of the levels of intergenerational equity applied thereby facilitating the difficult reconciliation of the cba technique with the objective of sustainability

double co2 and beyond benefits costs and compensation abstract economic decisions over what action if any to take concerning the greenhouse effect tend to revolve around the social discount rate implicitly the debate concerns how to attribute intertemporal weights to welfare and implies a moral stance that is rarely given explicit recognition refocusing on the outcomes of current actions emphasises the role of compensation a conflict is apparent between the view that the current generation need be unconcerned over the loss or injury caused to future generations because they will benefit from advances in technology investments in both man made and natural capital and direct bequests and the requirement to avoid harming the innocent changes in units of welfare cannot be viewed as equivalent regardless of their direction in general doing harm is not cancelled out by doing good the result is a rejection of the potential compensation principle which underlies the current economic stance and a reconsideration of the acceptability of compensation altogether the concept of human rights and a non utilitarian perspective are used to show how cost benefit analysis denies the existence of inalienable rights and economics limits the moral considerability of harm

gender differences in the allocation of assets in retirement savings plans in 1995 40 percent of working men and 32 percent of working women were covered by a defined contribution dc plan a distinguishing characteristic of these plans is that workers can generally choose how their assets are invested using data from the 1992 and 1995 surveys of consumer finances scf this paper examines whether workers differ systematically by gender in the allocation of assets in dc plans previous researchers have reported that many workers tend to invest their retirement assets too conservatively and in particular that women are less likely than men to invest in risky assets such as stocks in the presence of an equity premium a lower propensity by women to invest in stocks could translate into large differences in the accumulation of financial wealth for retirement we establish that gender differences in investment decisions exist though they are more complicated than previous studies have suggested we show that these differences are not completely explained by differences in individual or household characteristics a few studies have examined gender differences in investment decisions vickie l bajtelsmit and jack l vanderhei 1997 richard p hinz et al 1997 these studies use administrative data and report that women tend to invest their retirement funds in less risky vehicles than men michael haliassos and carol c bertaut 1995 use the 1983 scf to examine why such a large fraction of households do not own any stock they report that gender does not have a significant effect on the probability of owning stock though gender differences are not the focus of their paper what these data sources lack haliassos and bertaut being the exception is a rich set of demographic and other variables on households that theory predicts should affect investment behavior this paper adds to the literature by examining gender differences in investment decisions conditioning on such variables the results highlight the importance of including marital status risk aversion measures and the portfolio of assets held outside dc plans when examining gender differences in investment decisions in these plans

social security life insurance and annuities for families abstract in this paper we ask whether an aspect of social security namely its role as a provider of insurance against uncertain life spans is welfare enhancing to this end we use an olg model where agents have a bequest motive and differ in sex and marital status and where families are formed and destroyed and their characteristics evolve exogenously according to u s demographic patterns of marriage divorce fertility and mortality we compare the implications of social security under a variety of market structures that differ in the extent to which life insurance and annuities are available we find that social security is a bad idea in economies where the private sector provides annuities and life insurance it is a bad idea for the standard reason that it distorts the intertemporal margin by lowering the capital stock in the absence of such securities social security is still a very bad idea only marginally less so compared with economies with annuities and life insurance we also explore these issues in a world where people live longer and we find no differences in our answers as a by product of our analysis we find that the existence of life insurance opportunities for people is important in welfare terms while that of annuities is not

marriage and other risky assets a portfolio approach we study the joint impact of gender and marital status on financial decisions first we test the hypothesis that marriage represents in a portfolio framework a sort of safe asset and that this effect is stronger for women controlling for a number of observable characteristics we show that single women have a lower propensity to invest in risky assets than married females and males second we show that the differential behavior of single women evolves over time reflecting the increasing incidence of divorce and the expansion of female labor market participation in particular towards the end of our sample period we observe a reduction in the gap between women with different family status which can be attributed to the gradual erosion of the perception of marriage as a sort of safe asset our results therefore suggest that the differential behavior of single vs married women can be explained by the evolution of gender roles in society even after controlling for differential risk attitudes our empirical investigation is based on a dataset drawn from the 1989 2006 bank of italy survey of household income and wealth

electoral politics interest groups and the size of government electoral politics interest groups and the size of government i introduction interest groups have been considered main actors in the political drama for some time now by political scientists as in bentley 1908 schattschneider 1935 and truman 1951 and more recently by economist also such as olson 1965 and stigler 1975 despite the widespread consensus on their importance there have been few formal attempts to analyze their impact on public policies thus borooah and van der ploeg 1983 90 were moved to declare that theory based on the importance of different interest groups is badly needed in economics an important exception is becker s 1983 1985 analysis of interest group competition becker draws insights about the nature of the trade offs that occur when interest groups compete for political influence but becker consciously avoids incorporating into his model political institutions such as voting voting rules and candidates 1983 391 4 1985 330 rather he assumes that the political process operates as a veil through which the underlying strengths and demands of various interest groups are revealed this paper takes a different tack but one complementary to becker s approach the analysis is based on an explicit model of the political process that includes interest groups in the model interest group influence is a potential supply of votes for which parties or candidates compete each party seeks a winning coalition of voters and thus engages in implicit logrolling tullock 1959 572 an equilibrium exists in the competition for the support of interest groups and the nature of the equilibrium electoral platforms is identified below embodied in the characterization of the equilibria is a set of parameters that can be said to measure the strengths of the various interest groups and which enable one to identify how candidates change their policy positions in response to a change in the strength of an interest group it is therefore possible to analyze simultaneously the existence of an electoral equilibrium its nature including its normative properties and changes in equilibrium due to shifts in the balance of forces between competing groups 1 in contrast to becker 1983 1985 these analytical features are not assumed outright rather they are based on an underlying model of elections the theoretical underpinnings for this model are discussed in section ii interest groups are often alleged to be responsible in part for recent increases in the size of government in western democracies 2 therefore in sections iii and iv a model of the political process is used to study the impact of an increase in the influence of a particular interest group on government size in the simple models of the public sector considered here increasing group influence per se does not cause the size of the government to increase but an increase in the government s size does result when i there are constraints on the government s ability to change tax shares in response to a shift in group power or ii there is a publicly provided good which benefits one untaxed group and that group s sole concern with government policy is to maximize the amount of the good that it gets the paper concludes by considering some of the normative implications of the results ii interest groups in the electoral process there are two sets of actors in the model parties and interest groups and two sets of relationships which must be analyzed the relationships between interest groups and the parties and the relationship between the parties themselves with respect to the first question this paper investigates the determinants of each interest group s influence on the platforms proposed by the parties with respect to the second it explores whether the competition for votes between the parties produces an equilibrium and if so what its properties are

pollution from the electric power sector in japan and efficient pollution reduction abstract under the scheme of the kyoto protocol there are plans for the efficient reduction of carbon dioxide emissions in the electric power sector nuclear power generation which emits no carbon dioxide in the process of generating electricity has come under scrutiny however this energy produces a new environmental issue the disposal of radioactive waste first we derive shadow prices of carbon dioxide and low level waste as marginal abatement costs in the case of the electric power sector in japan employing a directional output distance function it is found that the shadow prices are us 39 per tonne for carbon dioxide and us 1531 per liter for low level waste secondly we calculate the indirect morishima elasticity between carbon dioxide and low level waste in order to identify their substitutability and it is found that the substitution of low level waste for carbon dioxide is easier than the reverse this result suggests that with the amount of generated electricity fixed carbon dioxide can be substituted more easily by low level waste when the relative price of carbon dioxide increases for example as a result of implementation of a carbon dioxide tax or an emissions trading system

distributional preferences and the incidence of costs and benefits in climate change policy we explore the relationship between willingness to pay wtp for climate change mitigation and distributional preferences by which we mean individuals opinions about who should be responsible for climate change prevention and whether the share of climate change impacts borne by the poor is a cause for concern we use 1 770 responses to an online stated preference survey the domestic costs in our survey s policy choice scenarios are expressed as a set of randomized shares across four different payment vehicles and the international cost shares are randomized across four groups of countries we also elicit respondents perceptions of the likely regressivity of climate change impacts under a policy of business as usual wtp is higher when larger cost shares are borne by parties deemed to bear a greater responsibility for mitigation and when respondents believe and care that the impacts of climate change may be borne disproportionately by the world s poor that wtp for an environmental policy depends on the distributional consequences of the policy is an unsettling result efficiency assessments are typically assumed to be separate from equity considerations in most benefit cost analyses

the determinants of household risky asset holdings australian evidence on background risk and other factors we study the portfolio allocation decisions of australian households using the relatively new household income and labour dynamics in australia hilda survey we focus on household allocations to risky financial assets our empirical analysis considers a range of hypothesised determinants of these allocations we find background risk factors posed by labor income uncertainty and health risk are important credit constraints and observed risk preferences play the expected role a positive age gradient is identified for risky asset holdings and home ownership is associated with greater risky asset holdings a unifying theme for many of our empirical findings is the important role played by financial awareness and knowledge in determining risky asset holdings many non stockholding households appear to lack the experience and financial literacy that might enable them to benefit from direct investment in stocks

are the economic costs of stabilising the atmosphere prohibitive abstract macro economic studies of the costs of reducing co2 emissions generally estimate the global cost of stabilising the atmospheric concentrations of co2 in the range 350 550 ppm in trillions of usd this creates the impression that the cost of co2 reductions is so large that it threatens economic development but presented in another way a completely different picture emerges there is widespread agreement amongst the more pessimistic macro economic studies that stringent carbon controls are compatible with a significant increase in global and regional economic welfare even if the cost of co2 abatement rises to 5 of global income per year by the end of this century this reduction is minor compared with the tenfold increase in global income that is expected since income is assumed to grow by a couple of percent per year the trillion usd cost could also be expressed as a few years delay in achieving an order of magnitude higher income levels similar observations can also be made as regards near term abatement targets such as the kyoto protocol a more widespread recognition of the fact that carbon abatement policies will only marginally affect economic growth is likely to increase the willingness to introduce carbon abatement policies

are women more risk averse we find that single women exhibit relatively more risk aversion in financial decision making than single men using u s sample data we examine household holdings of risky assets to determine whether there are gender differences in financial risk taking as wealth increases the proportion of wealth held as risky assets is estimated to increase by a smaller amount for single women than for single men gender differences in financial risk taking are also influenced by age race and number of children greater financial risk aversion may provide an explanation for women s lower levels of wealth compared with men s jel j16 d81 g11

gender based risk aversion and retirement asset allocation this research examines whether women have higher risk aversion than men as demonstrated by their retirement asset allocation the analysis is extended to investigate how retirement asset investment decisions are made in married households initial results suggest controlling for demographic income and wealth differences lead to no significant difference in the proportion of retirement assets held in stocks between women and male faculty for married households with joint investment decision making results indicate that gender differences are a significant factor in explaining individual retirement asset allocation our estimates imply that women faculty are more risk averse than their male spouse jel j16 g11 d10

did women s suffrage change the size and scope of government this paper examines the growth of government during this century as a result of giving women the right to vote using cross sectional time series data for 1870 1940 we examine state government expenditures and revenue as well as voting by u s house and senate state delegations and the passage of a wide range of different state laws suffrage coincided with immediate increases in state government expenditures and revenue and more liberal voting patterns for federal representatives and these effects continued growing over time as more women took advantage of the franchise contrary to many recent suggestions the gender gap is not something that has arisen since the 1970s and it helps explain why american government started growing when it did

bargaining and distribution in marriage the standard economic model of the family is a common preference model that assumes that a family maximizes a single utility function and implies that family behavior is independent of which individuals receive income or control resources in recent years this model has been challenged by game theoretic models of marriage that do not impose pooling and are therefore consistent with empirical evidence that income controlled by husbands and wives does have different effects on family behavior in this paper the authors review a number of simple bargaining models and relevant empirical evidence and discuss their implications for distribution within marriage

rethinking the costs related to global warming a survey of the issues one approach to the economic analysis of global warming seeks to balance the costs of damage from or adaptation to it with the costs of mitigating it the costs of adaptation and damage have been estimated using techniques of environmental evaluation but are subject to a wide margin of uncertainty the costs of mitigation principally by reducing the emissions of co2 have been estimated using different kinds of economic models some of the results of which have suggested that very little abatement of carbon emissions is justified before the costs of abatement exceed the benefits of it in terms of foregone damage and adaptation costs the paper analyses the extent to which this conclusion is a function of the modelling assumptions and techniques used rather than likely practical outcomes with regard to the models treatment of unemployed resources revenue recycling prior distortions in the economy due to the tax system and possible dynamic effects from the introduction of a carbon energy tax it concludes that with different and arguably more appropriate treatment of the above issues especially when the secondary benefits of reducing co2 emissions are also taken into account it is not clear that even substantial reductions in the use of fossil fuels will incur net costs especially if there is the prospect of even moderate costs from global warming

valuing lives equally distributional weights for welfare analysis abstract distributional weights for welfare analysis are proposed based on two axioms 1 all lives are equally valued 2 the monetary value of a person s life is her own valuation this implies weights proportional to the reciprocals of the values of statistical lives

global warming discounting is not the issue but substitutability is the cost benefit study of nordhaus 1994 is representative for the neoclassical approach towards global warming nordhaus found that no substantial emission cuts are warranted most of his critics have concentrated on the issue of discounting and demanded that a lower discount rate should be applied these criticisms first miss the point and second lead to ethically dubious inconsistent conclusions and inefficient policy choices they miss the point because the real problem of nordhaus s methodology is his implicit underlying assumption of perfect substitutability between natural and other forms of capital given the validity of this assumption lowering the rate of discount is inconsistent with current savings behaviour is ethically dubious because future generations will be much richer than the current one anyway and is inefficient because scarce financial resources are channelled into emissions abatement that exhibits rates of return far inferior to alternative public investments any call for aggressive emission abatement must therefore directly attack the perfect substitutability assumption of neoclassical economics the real disagreement is about whether consumption growth can compensate for environmental degradation caused by global warming discounting is not the issue but substitutability is

time preference in global warming calculations a proposal for a unified index abstract many aspects of the calculation of the impacts of greenhouse gas ghg emissions and the costs and benefits of possible response options are highly sensitive to the way in which time preference is incorporated into the computations the intergovernmental panel on climate change ipcc used global warming potentials gwps to standardize inputs of different gases with differing radiative forcings and atmospheric lifetimes in the results emphasized by the ipcc s second assessment report a 100 year time horizon and no discounting is used and this has been adopted by the kyoto protocol for use in the first commitment period 2008 2012 here an alternative unified index is proposed that assigns explicit weights to the interests of different generations in contrast to discounting including the zero discount rate used by the ipcc the generationally weighted index forces policy makers to face the moral assumptions that underlie their choices related to global warming

the effects of marital status and children on savings and portfolio choice this paper investigates the impact of demographic shocks on optimal decisions about saving life insurance and most centrally asset allocation we analyze these choices within the framework of a life cycle model that features exogenous changes in family composition heterogeneity in lifetime income and uninsurable fluctuations in earnings and medical costs our analysis indicates that marital status transitions and children can have important effects on optimal household decisions widowhood induces sharp reductions in the portfolio shares in stock and the impact is largest for women and individuals with children divorce causes men and women to reallocate their portfolios in different directions men choose much riskier allocations while women opt for safer ones children play a fundamental role in the optimal portfolio decisions men with children for example increase their shares in response to divorce by less than half as much as men without children comparing our simulation results with panel data evidence on stockholding from the psid and the hrs we conclude that changes in marital status and children matter empirically as well but not always in the ways that the model predicts

optimal climate policy is a utopia from quantitative to qualitative cost benefit analysis abstract the dominance of quantitative cost benefit analysis cba and optimality concepts in the economic analysis of climate policy is criticised among others it is argued to be based in a misplaced interpretation of policy for a complex climate economy system as being analogous to individual inter temporal welfare optimisation the transfer of quantitative cba and optimality concepts reflects an overly ambitious approach that does more harm than good an alternative approach is to focus the attention on extreme events structural change and complexity it is argued that a qualitative rather than a quantitative cba that takes account of these aspects can support the adoption of a minimax regret approach or precautionary principle in climate policy this means implement stringent ghg reduction policies as soon as possible

discounting and distributional considerations in the context of global warming the economics of global warming is reviewed with special emphasis on how the cost depends on the discount rate and on how costs in poor and rich regions are aggregated into a global cost estimate both of these factors depend on the assumptions made concerning the underlying utility and welfare functions it is common to aggregate welfare gains and losses across generations and countries as if the utility of money were constant but it is not if we assume that a e co2 equivalent dlubling implies costs equal to 1 5 of the income in both high and low income countries a pure rate of time preference equal to zero and a utility function which is logarithmic in income then the marginal cost of co2 emissions is estimated at 260 590 usd ton c for a time horizon in the range 300 1000 years an estimate which is large enough to justify significant reductions of co2 emissions on purely economic grounds the estimate is approximately 50 100 times larger than the estimate made by nordhaus in his dice model and the difference is almost completely due to the choice of discount rate and the weight given to the costs in the developing world as well as a more accurate model of the carbon cycle finally the sensitivity of the marginal cost estimate with respect to several parameters is analyzed

the social cost of carbon and its policy implications the shadow price or social cost of carbon is an important indicator of the global incremental damage done by emitting greenhouse gases today cost benefit analysis would set the optimal amount of greenhouse gas emission reduction at the point where this social cost just equals the incremental cost of controlling emissions the higher the value for the social cost of carbon the more control is warranted this comparison assumes that cost benefit analysis is the correct way of determining climate change policy and many believe this is not the case because of the very long term irreversible and potentially catastrophic nature of global warming but in the short run at least a comparison of cost and benefits is required and in any event all decisions imply costs and benefits but what is the right figure for the social cost of carbon this paper reviews the uk government s assessment of the cost and concludes that it has been set far too high because of a misreading of the integrated assessment models used to balance costs and benefits moreover adoption of the uk government s shadow price would have formidable implications for energy policy in the uk and for policies on afforestation copyright 2003 oxford university press

distributional biases in the analysis of climate change abstract the economic analysis of global warming is dominated by models based on optimal growth theory these representative agent models have an intrinsic distributional bias in favor of the rich the bias is compounded by the use of revenue neutrality in the allocation of emission permits the result is mitigation recommendations that are biased downwards

disaggregated economic impact analysis incorporating ecological and social trade offs and techno institutional context a case from the western ghats of india economic valuation of ecosystem benefits and their aggregation in a benefit cost analysis bca framework is the norm in mainstream environmental economics but valuation and bca have also attracted criticisms internal criticisms point to the absence of alternative scenarios in valuation overlooking of ecological trade offs and dis services and inattention to context others criticize aggregation across diverse stakeholders and the problem of non monetizable benefits and dismiss bca as fatally flawed they suggest approaches such as deliberative decision making and multi criteria analysis we propose a middle path that uses the strengths of economic analysis for decision support while avoiding the pitfalls we disaggregate economic impacts by stakeholder groups link ecosystem changes to benefits as well as dis benefits and examine how socio technological context shapes the magnitude of economic impact we illustrate this approach by studying the impact of creating the biligiri rangaswamy temple wildlife sanctuary in the western ghats forests of southern india our analysis shows that while some stakeholders are net beneficiaries others are net losers changes in forest rights irrigation technologies and ecosystem dynamics influence the magnitude of benefits and sometimes convert gainers into losers such disaggregated analysis can provide useful information for deliberative decision making and important academic insights on how economic value is generated

convex time budgets and individual discount rates in the long run the purpose of this study is to use experimental data to estimate individual discount rates and test for hyperbolic discounting over a long time horizon to do this we employ the convex time budget experimental approach with cash payments over a 20 year time horizon to date there are few experimental studies that explore discount rates beyond a 1 year time horizon previous experimental studies that focus on short time horizons find high discount rates which may not be applicable to decisions that affect outcomes in the distant future our findings are quite similar to the average rate of 4 9 found by grijalva et al environ resour econ 59 39 63 2014 who similarly use a 20 year time horizon but use the multiple price list elicitation method along with payment via government savings bonds we find annual discounts rates in the range of 1 9 5 5 depending on the specific model used we also find evidence for declining discount rates and that this hyperbolic pattern of behavior is related to the confidence subjects have in receiving distant future payments

does britain or the united states have the right gasoline tax this paper develops an analytical framework to assess the second best optimal level of gasoline taxation taking into account unpriced pollution congestion and accident externalities as well as interactions with the broader fiscal system we provide calculations of the optimal taxes for the us and the uk under a variety of parameter scenarios under our central parameter values the second best optimal gasoline tax is 1 01 gal for the us and 1 34 gal for the uk current tax rates are much lower than this in the us and higher in the uk the calculations are moderately sensitive to alternative parameter assumptions the congestion externality is the largest component in both nations revenue raising needs also play a significant role as do accident externalities and local air pollution potential welfare gains from reducing the current uk tax rate are estimated at nearly one fourth the production cost of all gasoline used in the uk even larger gains could be achieved by switching to a tax on vehicle miles with equal revenue yield for the us the welfare gains from optimizing the gasoline tax are smaller but those from switching to an optimal tax on vehicle miles are very large

planning and financial literacy how do women fare many older us households have done little or no planning for retirement and there is a substantial population that seems to undersave for retirement of particular concern is the relative position of older women who are more vulnerable to old age poverty due to their longer longevity this paper uses data from a special module we devised on planning and financial literacy in the 2004 health and retirement study it shows that women display much lower levels of financial literacy than the older population as a whole in addition women who are less financially literate are also less likely to plan for retirement and be successful planners these findings have important implications for policy and for programs aimed at fostering financial security at older ages

research frontiers in the economics of climate change academic and policy debates over climate change risks and policies have stimulated economic research in a variety of fields in this article i briefly discuss eight overlapping areas of current research in which further effort is particularly warranted these areas include decision criteria for policy risk assessment and adaptation uncertainty and learning abatement cost and the innovation and diffusion of technology and the credibility of policies and international agreements further analysis in these areas not only will advance academic understanding but also will provide insights of considerable importance to policymakers

toward consilience between biology and economics the contribution of ecological economics abstract during its ten year history ecological economics has made a real difference in the way economists look at the natural world and in the way biologists look at the economy in this survey article we examine the contributions to the journal in terms of e o wilson s concept of consilience that is his argument that the methods and assumptions of any field of study should be consistent with the known and accepted facts in other disciplines in particular we examine the contributions of ecological economics to reconciling the economic theory of the consumer and producer with biophysical reality

did unilateral divorce raise divorce rates evidence from panel data since early 1996 at least eight states have begun to consider rolling back unilateral and no fault divorce a major reversal of the liberalizing trend in divorce laws which began around 1970 the proponents of tightening the divorce regime often argue that making divorce more difficult will strengthen families however both theoretical and empirical evidence is decidedly mixed over whether the no fault revolution actually contributed to the sharp increase in divorce rates in the united states observed over the last 30 years in this paper i address the dispute by using a panel of state level divorce rates including state specific trends allows unobserved state divorce propensities to trend linearly and even quadratically over time and reveals that unilateral divorce raised divorce rates significantly and strongly excerpt

intergenerational discounting with intragenerational inequality in consumption and the environment it is now established that the consumption discount rate is determined by the growth of consumption multiplied by the elasticity of marginal utility but distributive concerns are rarely reflected in the literature assuming a social welfare function with inequality aversion we consider a consumption discount rate that can be decomposed into the growth effect and the intragenerational distribution effect the framework is then extended to include population change and inequality in the environment as an amenity in a utility with constant elasticity of substitution numerical examples illustrate that distributional effects turn non negligibly negative that may reduce consumption discount rate by 1 3 for plausible parameters once distribution is adjusted for both population and the environment

marriage and divorce changes and their driving forces the family is not a static institution in recent decades marriage rates have fallen divorce rates have risen and the defining characteristics of marriage have changed the economic approach to the family seeks to explain these trends by reference to models that can also explain how and why families form gary becker s 1981 treatise on the family proposed a theory based on production complementarities in which husband and wife specialize in the market and domestic spheres respectively production complementarities also arise in the production and rearing of one s own children however production complementarities at least as initially described are decreasingly central to modern family life increased longevity and declining fertility mean that most of one s adult life is spent without one s own children in the household also the rise in marital formation at older ages including remarriage means that many families form with no intention of producing children moreover increases in female labor force participation suggest that household specialization has either declined or at least taken on a different meaning these changes have come about as what is produced in the home has been dramatically altered both by the emergence of labor saving technology in the home and by the development of service industries that allow much of what was once provided by specialized homemakers to be purchased in the market the availabil

who holds the purse strings within the household the determinants of intra family decision making abstract we study the determinants of intra household decision making responsibility over economic and financial choices using a direct measure provided in the 1989 2010 bank of italy survey of household income and wealth we find that the probability that the wife is responsible for decisions increases as the wife s characteristics in terms of age education and income become closer or even higher than those of her husband s thus consistently with a bargaining approach decision making responsibility is associated with marriage heterogamy and not only along strictly economic dimensions however in support of an alternative household production approach we also find that the probability that the wife is responsible is lower when she is employed which suggests the presence of a specialization pattern assigning responsibility to the spouse with more available time our results are robust to additional controls and alternative samples

the greenhouse effect and intergenerational transfer abstract the scientific basis for understanding the economic issues involved in the greenhouse effect is outlined four important aspects of the problem are identified and discussed irreversibility international and institutional constraints uncertainty and intergenerational equity attention is focused upon the intertemporal choice problem a model describing the potential for intergenerational transfers under the uncertainty of climatic change due to fossil fuel combustion is presented we conclude intergenerational compensation can be achieved by investment in capital or technology or by bequest and is ethically required regardless of any other action

housing decision with divorce risk we build a realistically calibrated life cycle model of housing decisions under divorce risk as observed in the data our model predicts the recent increase in divorce rates leads to reduced homeownership rates the event of a divorce negatively affects homeownership and this effect is long lasting the risk of a divorce triggers a precautionary savings motive however this motive is weaker when individuals can invest in owner occupied homes because homeowners higher savings partially substitute for precautionary savings when young the larger asset accumulation due to divorce risk induced precautionary savings enables households to buy homes earlier whereas the presence of transaction costs leads to reduced homeownership for middle aged and older households when divorce risk goes up

the effects of ageing and an environmental trust fund in an overlapping generations model on carbon emission reductions most currently employed integrated assessment models for climate change are of a dynastic nature they employ the ramsey rule linking the interest rate economic growth and the rate of pure time preference this paper argues that although a dynastic framework might be convenient for economic analysis it is restrictive and can be misleading overlapping generations models which do not employ the ramsey rule are more flexible and may give results different from those derived from dynastic models with the integrated assessment model alice 2 0 it is shown how various assumptions on demographic change and public institutions can affect the interest rate thereby influencing the efficient greenhouse gas emission reductions it is concluded that dynastic integrated assessment models are in many respects inappropriate for providing policy makers with quantitative figures about the costs of carbon dioxide emissions and their desirable reduction levels 2001 elsevier science b v all rights reserved

ethics and the limits of environmental economics abstract the purpose of this paper is to establish the limits of the cost benefit framework used by environmental economists given the acceptance of an ethic of environmental concern two approaches to environmental ethics will be considered one based on the view that human beings are the focus of moral concern and another based on the notion that moral concern can be extended to the non human natural world as well if human beings are morally considerable cost benefit analysis can be legitimately applied to environmental issues involving the pursuit of human well being so long as those who suffer losses from environmental damage are adequately compensated however the application of cost benefit analysis to environmental issues is inconsistent with the moral considerability of human beings in cases where environmental damage is harmful to human health and in cases where the natural environment is so highly valued that the compensation of damaged parties is infeasible moreover cost benefit analysis cannot be legitimately applied where non human natural entities are viewed as morally considerable

persistency of financial distress amongst italian households evidence from dynamic models for binary panel data abstract this paper builds on existing studies on households financial distress and provides new evidence on the determinants of financial hardship in italy and its persistence over time it suggests a quantitative definition of financial distress based on the distribution of net wealth and tests whether the probability of experiencing financial difficulty is persistent over time using random and fixed effects dynamic models for binary panel data the analysis exploits the longitudinal component of the bank of italy survey on household income and wealth for the period 1998 2006 its results show that after accounting for unobserved heterogeneity past values of the outcome variable play a large part in explaining the probability of experiencing financial distress in addition the probability of financial vulnerability decreases with income and greater sophistication of the household portfolio and at least in one of the model specifications increases in areas with higher unemployment rates

on international equity weights and national decision making on climate change abstract estimates of the marginal damage costs of carbon dioxide emissions require the aggregation of monetised impacts of climate change over people with different incomes and in different jurisdictions implicitly or explicitly such estimates assume a social welfare function and hence a particular attitude towards equity and justice we show that previous approaches to equity weighting are inappropriate from a national decision maker s point of view because domestic impacts are not valued at domestic values we propose four alternatives sovereignty altruism good neighbour and compensation with different views on concern for and liability towards foreigners the four alternatives imply radically different estimates of the social cost of carbon and hence the optimal intensity of climate policy

the behavioural economics of climate change this paper attempts to bring some central insights from behavioural economics into the economics of climate change in particular it discusses i implications of prospect theory the equity premium puzzle and time inconsistent preferences in the choice of discount rate used in climate change cost assessments and ii the implications of various kinds of social preferences for the outcome of climate negotiations several reasons are presented for why it appears advisable to choose a substantially lower social discount rate than the average return on investments it also seems likely that taking social preferences into account increases the possibilities of obtaining international agreements compared to the standard model however there are also effects going in the opposite direction and the importance of sanctions is emphasized

leaving oil underground in ecuador the yasuni itt initiative from a multi criteria perspective abstract the ecuadorian proposal to keep 846 million barrels of crude oil in the yasuni national park underground for the purposes of avoiding co2 emissions and to protect both the biological diversity and the indigenous peoples in isolation who inhabit this area of the amazon is evaluated from a multi criteria analysis the main purpose of the paper is to compare this policy option with other alternatives across different values an analytical framework is used that recognises the inherent complexity of a problem of this nature in which the financial values are indeed relevant for policy but other values are also relevant the economic in a broad sense social environmental cultural and political the results confirm that from a financial standpoint extracting the oil is preferable but by incorporating the non monetary values into the multi criteria decision process one can plausibly defend the yasuni itt initiative as the most desirable policy option indeed the social and environmental benefits or criteria signalling an economic transition towards a model based on renewable sources of energy along with the protection of critical environmental and social capital make up for the financial gap

weight factors in cost benefit analysis of climate change equity considerations may justify the use of weight factors when estimating the costs of climate change this paper reviews different weight factors that have been used in the climate economics literature based on a simple model it is shown that although the different weight factors imply substantially different cost damage estimates they actually yield the same optimal emission reductions this paradox is explained by the fact that some of the approaches require that also the abatement costs are weighted and this offsets the effect of the diverging cost damage estimates the model is then used to analyse the importance weighting may have on the overall cost benefit analysis at present when most of the global emissions of fossil co2 originate from the industrialised countries the global optimal emissions are considerably lower if costs are weighted however the more the emissions in developing countries grow the less important becomes the introduction of weight factors in cost benefit analysis of climate change for the global emission reductions in the model developed here on a regional level the introduction of weight factors continues to play an important role implying substantially lower emissions in the rich region and slightly higher in the poor

a regulatory framework for a policy of sustainability lessons from the neo liberal school abstract in this paper targets institutions and policy measures for describing and implementing sustainable development are evaluated in terms of their conformity with the economic framework of a market system from the viewpoint of neo liberal economic thinking as conceived by the german freiburg school of economists a general set of criteria is developed it includes issues of operationalization and legitimation of goals as well as institutional and instrumental issues on this basis general rules for designing an ecological framework guaranteeing the greatest possible degree of conformity with a market system are derived the concrete application of these rules leads to recommendations for a policy of sustainability with respect to the setting of goals the establishment of institutions as well as the use of appropriate instruments

understanding the effects of marriage and divorce on financial investments the role of background risk sharing we investigate how changes in marital status affect financial investments and how these effects vary with background risk we use detailed register based panel data and difference in differences estimators to benchmark common unobserved influences on financial investments women increase the fraction of wealth invested in stocks after marriage and decrease it after divorce whereas men show the opposite behavior households whose joint labor income risk is reduced more by marriage have a higher increase in their exposure to risky assets in marriage thus income risk sharing in the household is important for financial risk taking and investment responses to marital transitions jel g11 j12 j16 d14

targets for global climate policy an overview a survey of the economic impact of climate change and the marginal damage costs shows that carbon dioxide emissions are a negative externality the estimated pigou tax and its growth rate are too low to justify the climate policy targets set by political leaders a lower discount rate or greater concern for the global distribution of income would justify more stringent climate policy but would imply an overhaul of other public policies catastrophic risk justifies more stringent climate policy but only to a limited extent

families as shocks in this paper we show the quantitative importance of the process that determines changes in family composition to determine the main macroeconomic magnitudes we do so by modelling family type as a stochastic process that affects households in a way similar to shocks to earnings agents respond to these process by optimally choosing savings we show that the size of savings differs dramatically depending on the details of the stochastic process the model is quantitative its fundamental parameters are estimated using u s data

financial decision making are women really more risk averse 40 males 33 females gain gambling gain domain loss gambling loss domain a contextual frames b abstract gambling frames studies the application of experimental methods provided stronger control of the economic environment in which decisions were made we elicited data which call into question the prevalence of stereotypic risk attitudes in financial decision making first we find that the comparative risk propensity of male and female subjects is strongly dependent on the financial decision setting second and more important we observe no gender differences in risk propensity when subjects face contextual decisions since in practice financial decisions are always contextual our results suggest that the above gender stereotype may not reflect true male and female attitudes toward financial risks i gender specific risk behavior an experimental design our experiment was designed to examine gender specific risk propensity in decisions relevant for investors and managers table 1 gives an overview of the experimental design in the main treatment we implemented risky choices in the form of investment and insurance decisions choice behavior in this treatment henceforth called the context treatment directly measures the risk behavior of male and female subjects in contextual financial decisions we also ran a control treatment in which the same risky choices were presented as abstract gambling decisions this control treatment henceforth called the abstract treatment allows us to validate the risk behavior induced by our experimental procedure in the light of the above mentioned gambling evidence in the context treatment subjects were confronted with risky choices in two different decision contexts subjects first had to complete a series of investment decisions they were then presented with a series of identical choices this time however framed as insur1 wealth effects from income differences outside the laboratory may still affect risk behavior in our experiment they are controlled for in our model 2 experimental instructions are available in german from the authors or in english from our web page www wif ethz ch publikationen htm ance decisions each investment and insurance decision incorporated a choice between a risky lottery and a certain payoff with the series of choices implemented in the two frames we elicited our subjects certainty equivalents for the same four risky lotteries l1 l2 l3 l4 in both contexts we implemented two frames in the context treatment in order to measure the risk propensity of subjects toward both perceived gains and perceived losses in both frames all possible payoffs for each decision were positive in the investment frame these payoffs were also presented as gains while in the insurance frame the same payoffs were presented as losses relative to an initial endowment therefore elicited certainty equivalents in the investment frame measure subjects risk propensities in the gain domain while certainty equivalents in the insurance frame measure risk propensity in the loss domain if in contextual financial decisions female subjects are generally more risk averse than men our results should display ceteris paribus lower female certainty equivalents in both the investment and insurance frames 3 the four lotteries l1 l2 l3 and l4 each had two possible outcomes payoffs in swiss francs 1 sfr a 0 60 and their probabilities were 30 sfr 6 10 sfr 6 30 sfr 2 10 sfr 2 30 sfr 6 10 sfr 6 and 50 sfr 2 20 sfr 2 respectively 4 experimental evidence suggests that individual risk propensity will vary systematically between the gain and loss domain daniel kahneman and amos tversky 1979 383 vol 89 no 2 gender and economic transactions 3y16 my68 mp 383 friday dec 10 08 20 am lp aer my68 figure 1 differences in mean certainty equivalents ce between male and female subjects by frame note certainty equivalents and male female differences are measured in swiss francs in the abstract treatment we confronted a different group of subjects with exactly the same risky decisions as those in the main treatment however as mentioned before all choices in this control treatment were framed as abstract gambling decisions again two frames were implemented in the gaingambling and loss gambling frames we measured the risk attitudes of subjects toward gambles in the gain and loss domain respectively subjects in both treatments were told in advance that one of their choices would determine their experimental earnings further all subjects completed a post experimental questionnaire which yielded information on each subject s disposable income this information is necessary to exclude wealth effects due to income differences outside the laboratory as an explanation of gender specific choice behavior

intergenerational equity discounting and the role of cost benefit analysis in evaluating global climate policy when public policies with impacts far into the future are being debated the question inevitably is raised whether cost benefit analysis which discounts future costs and benefits is not biased against future generations and whether if such discounting is appropriate at all a lower rate should be used to avoid such bias the debate on global climate change is no exception this paper sketches and analyses the welfare foundations of cost benefit analysis and from this perspective analyses the role of cost benefit analysis in the climate policy debate particularly with reference to intergenerational effects the paper concludes that the cost benefit criterion cannot provide a definitive basis for deciding whether we should commit to a longer term programme to moderate climate change the issues of intergenerational equity are not that global climate change will significantly lower the gnp of future generations but relate to the possibility of science fiction like changes in the planet that will produce catastrophic effects in the future and the typical way in which the cost benefit problem is posed obscures the basic choices that we should be evaluating

on the value of life in rich and poor countries and distributional weights beyond utilitarianism this paper discusses the use ofdistributional weights in cba based on a generalbergson samuelson swf in particular it illustratessome consequences of applying a swf characterized byconstant inequality aversion which includes classicalutilitarianism as a special case together with aconstant relative risk aversion utility function whencalculating the damage costs of global warming itextends and clarifies earlier unintuitive results andemphasizes that utility must be seen as fully cardinalin terms of levels in this context in the specialcase of utilitarianism on the other hand it issufficient to be able to make interpersonalcomparisons of utility changes

gender gap in peer to peer lending evidence from china abstract this paper documents and analyzes the gender gap in the online credit market using data from renrendai a leading peer to peer lending platform in china we show that lending to female borrowers is associated with better loan performance including a lower probability of default a higher expected profit and a lower expected loss than for their male peers however despite the higher creditworthiness we don t find any measurable gender impact on funding success rate meaning that female borrowers have to compensate lenders by providing higher profitability to achieve a similar funding probability these evidences indicate the existence of a gender gap that discriminate against female borrowers further analysis implies that this gender gap is independent of the amount of information disclosed by borrowers

the impact of climate change on the balanced growth equivalent an application of fund the stern review added balanced growth equivalents bge to the economic climate change research agenda we first propose rigorous definitions of the bge for multiple regions and under uncertainty we show that the change in the bge is independent of the assumed scenario of per capita income for comparable welfare economic assumptions as the stern review we calculate lower changes in bge between a business as usual scenario and one without climate impacts with the model fund than the stern review found with the model page we find that mitigation policies give even lower changes in bge and argue that those policy choices should be the focus of the research effort rather than total damage estimates according to our results the current carbon tax should be below 55 tc sensitivity analyses show that the stern review chose parameters that imply high impact estimates however for regionally disaggregated welfare functions we find changes in bge that are significantly higher than the results from the stern review both for total damage as for policy analysis with regional disaggregation and high risk aversion we observe fat tails and with that very high welfare losses

health status and portfolio choice causality or heterogeneity abstract this paper explores the role of unobserved individual characteristics in the health assets and health portfolio correlations we apply various econometrics models to a unique longitudinal dataset with rich information that allows for the exploitation of four different health indices our findings show strong cross sectional correlations between health and both financial and non financial assets but these correlations seem to be mainly driven by heterogeneity as the correlations largely disappear in the fixed effects model adverse health shocks however are found to motivate a safer portfolio choice even after individual fixed effects are controlled for a result consistent with the prediction made by the background risk theory our findings suggest that health shocks shift investment from risky assets toward other financial assets but keep the total financial assets unchanged

does better discounting lead to worse outcomes in long run decisions the dilemma of hyperbolic discounting the shortcomings of conventional discounting especially in the context of long run environmental problems have been extensively discussed in the literature recently hyperbolic discounting i e discounting at declining instead of constant discount rates has attracted a lot of interest among both scientists and politicians although there are compelling arguments for employing hyperbolic discounting there are also pitfalls which have to be pointed out in this paper i show that the problem of time inconsistency an inherent characteristics of hyperbolic discounting leads to a potential clash between economic efficiency and intergenerational equity as an example i refer to the weak progress in the controlling of greenhouse gas emissions under the kyoto protocol as the problem of time inconsistency cannot be solved on economic grounds alone there is a need for an intergenerational moral commitment

the damage costs of climate change toward more comprehensive calculations it is argued that estimating the damage costs of a certain benchmark climate change is not sufficient what is needed are cost functions and confidence intervals although these are contained in the integrated models and their technical manuals this paper brings them into the open in order to stimulate discussion after briefly reviewing the benchmark climate change damage costs region specific cost functions are presented which distinguish tangible from intangible losses and the losses due to a changing climate from those due to a changed climate furthermore cost functions are assumed to be quadratic as an approximation of the unknown but presumably convex functions results from the damage module of the integrated climate economy model fund are presented next uncertainties are incorporated and expected damages are calculated it is shown that because of convex loss functions and right skewed uncertain ties the risk premium is substantial calling for more action than analysis based on best guess estimates the final section explores some needs for further scientific research

environmental sustainability as the first principle of distributive justice towards an ecological communitarian normative foundation for ecological economics abstract the ecological economic concern with environmental sustainability embodies the normative orientations of the field this concern is foremost a matter of distributive justice the definition of which determines the relevance of the appropriate scale and efficient allocation criteria yet it would appear that the discipline lacks a shared internally consistent set of ethical premises by which this concern might be legitimized various authors have embraced a rawlsian conception of liberal justice as the appropriate banner for ecological economics in place of the consequentialist libertarian foundations of neoclassical economics including environmental economics it is argued here that this is insufficient in so far as it is premised on a vision of a discrete self sufficient economic actor instead it is posited that an ecological economic ethic must proceed from an understanding of the economic actor as community member a recognition implicit in recent ecological economic contributions focused on discourse ethics and deliberative democracy an ecological communitarian conception of distributive justice which views the well being of the individual as inseparable from the integrity of its implicate mutually constituting human and non human natural communities is advanced as the appropriate basis for the ecological economic world view in this light the thermodynamic foundations of ecological economics are seen to provide the necessary departure point for normative decision making oriented towards ensuring sustainability in economic organization

why have women become left wing the political gender gap and the decline in marriage the last three decades have witnessed the rise of a pohtical gender gap in the united states wherein more women than men favor the democratic party we trace this development to the decline in marriage which we posit has made men richer and women poorer data for the united states support this argument first there is a strong positive correlation between state divorce prevalence and the political gender gap higher divorce prevalence reduces support for the democrats among men but not women second longitudinal data show that following marriage divorce women are less more likely to support the democratic party

do oligopolists earn noncompetitive rates of return high in effect is defined in this proposition in either of two ways most commonly it has been taken to mean high enough to warrant remedial intervention of some sort by the state 4 recently however a growing minority of economists has urged that it be taken to mean instead high enough to warrant intervention provided the state can show that rates of return in excess of r1 reflect collusive behavior by the leading firms and not cost advantages which these firms have over their leading rivals both meanings in turn reflect a third high enough to imply a typical market price closer to pm in figure lb than to pc where pm is the price that would prevail if the leading firms maximized collective current period profits and pc is the price that would prevail if collective current period profits approximated zero 6 proposition 1 rests on a large body of empirical work proposition 2 however does not nor does it rest on any theoretical analysis industrial economists simply have intuited that there is a correspondence between the r1r2 segment in figure la and the pmp segment in figure lb are there substantive grounds for the intuition i argue that there are not the rates of return that lie along the r1r2 segment are competitive