imprecise information disclosure and truthful certification abstract this article studies the interaction of information disclosure and reputational concerns in certification markets we argue that by revealing information less precisely a certifier reduces the threat of capture because this reduces her gains from selling fraudulent certificates as a result only imprecise disclosure rules are implementable for intermediate discount factors our results therefore suggest that contrary to the common view imprecise disclosure may be socially desirable regulatory intervention may provoke market failure especially in industries where certifier reputational rents are low

decarbonizing residential building energy a cost effective approach abstract given the problem of climate change the world economy must eventually switch to carbon neutral energy in this study we present a cost effectiveness approach given a goal of decarbonization the objective is to accomplish this at minimum cost for residential building energy we show that total cost is minimized by equating marginal cost of building energy conserved with marginal cost of obtaining carbon free energy where we express costs of both in dollars per kwh we describe how the cost of solar photovoltaic energy provides an upper bound on the marginal cost of carbon free energy and thus an upper bound on marginal cost of conserved energy one should not necessarily spend more on energy conservation than the cost of photovoltaic energy though there are several caveats a case study from vermont usa illustrates these principles and implementation issues with marginal analysis of energy conservation from a policy perspective the principles presented suggest that either carbon taxes or carbon limits could be used to decarbonize building energy at minimum cost but that approaches using renewable energy subsidies or prescriptive building codes result in greater decarbonization costs to society this suggests that new policy approaches be adopted

fat tails exponents extreme uncertainty simulating catastrophe in dice abstract the problem of low probability catastrophic risk is increasingly central to discussion of climate science and policy but the integrated assessment models iams of climate economics rarely incorporate this possibility what modifications are needed to analyze catastrophic economic risks in an iam we explore this question using dice a well known iam we examine the implications of a fat tailed probability distribution for the climate sensitivity parameter a focus of recent work by martin weitzman and the shape of the damage function one of the issues raised by the stern review forecasts of disastrous economic outcomes in dice can result from the interaction of these two innovations but not from either one alone

rational heuristics expectations and behaviors in evolving economies with heterogeneous interacting agents we analyze the individual and macroeconomic impacts of heterogeneous expectations and action rules within an agent based model populated by heterogeneous interacting firms agents have to cope with a complex evolving economy characterized by deep uncertainty resulting from technical change imperfect information coordination hurdles and structural breaks in these circumstances we find that neither individual nor macroeconomic dynamics improve when agents replace myopic expectations with less naive learning rules our results suggest that fast and frugal robust heuristics may not be a second best option but rather rational responses in complex and changing macroeconomic environments jel c63 d8 e32 e6 o4

valuing nuclear energy risk evidence from the impact of the fukushima crisis on u s house prices abstract behavioral economics suggests that individuals overweight recent unexpected and or rare events when updating beliefs this study investigates the effect of such an event the fukushima nuclear crisis in 2011 on the learning process of a local environmental risk by evaluating how perceptions of the risk of a nuclear accident are capitalized into house prices near nuclear power plants npps in the u s our results provide new evidence on the dynamics of the effect spatially the impact was concentrated in a 4 km radius around npps and temporally it peaked a half year later and dissipated one year after the crisis

the equivalency principle for discounting the value of natural assets an application to an investment project in the basque coast making decisions about optimal investments in green infrastructure necessitates setting social discount rates this paper suggests a practical way for determining the discount rate for projects or programmes in which one of the options is to maintain or improve land in its natural state we propose an a equivalency principlea to derive a simple rule that sets the discount rate the rule is based on the premise that the long term value of a naturally preserved land track ought to be at least the same as the value of an identical land track in the vicinity to which permission has been granted for development we illustrate this principle with various case studies and we apply it to a contentious investment project in the basque country associated with the regeneration of a large scale harbour in the province of gipuzkoa north of spain that involves reclaiming natural land that has important ecological value including for the conservation of a marine ecosystem

an empirical examination of quality certification in a lemons market i introduction researchers have long understood that a variety of mechanisms may be used to overcome problems of adverse selection stigler 1961 224 notes that s ome forms of economic organization may be explicable chiefly as devices for eliminating uncertainties in quality and akerlof 1970 cites independent groups such as the consumers union and united laboratories that test and certify the quality of goods there is however little empirical evidence that illustrates the effectiveness of such mechanisms in this article we examine the effect certification has on a market characterized by adverse selection using data from the market for young thoroughbreds we compare the performance of sales where auction houses provide certification services with sales where certification is absent the thoroughbred racehorse market consists of two distinct types of public auctions certified and noncertified sales in a certified sale auction houses physically inspect the horses nominated to their sales selling only the horses they conclude are from the upper end of the quality distribution in noncertified sales auction houses sell all horses nominated to a sale our empirical strategy is to perform tests that indicate whether adverse selection affects market outcomes in either certified or noncertified sales a finding that adverse selection is present in noncertified sales but absent in certified sales is consistent with the hypothesis that certification alleviates problems of adverse selection we adopt three approaches to test for the presence of adverse selection 1 the first approach is in the spirit of chiappori and salanie 2000 who examine the relationship between unobservable factors from participation and performance equations we model adverse selection as a case of sample selection bias and examine the correlation between errors in participation and price equations 2 to accomplish this we use a unique data set that allows us to estimate how breeder decisions to sell or retain horses affect market prices the data set consists of a 10 random sample of all thoroughbreds born in 1993 and includes both horses retained by their breeders who own a horse at the time of its birth and horses that breeders chose to sell our second test follows genesove 1993 and chezum and wimmer 1997 by examining the relationship between seller characteristics and price theoretically when observable seller characteristics are correlated with seller incentives to select goods adversely prices should reflect these differences chezum and wimmer observe that some breeders sell all of their horses whereas others retain a portion to race they find that market prices are inversely related to the extent of a breeder s involvement in racing concluding that adverse selection affects market outcomes we extend this work in two respects first we isolate the effect seller characteristics have on price through the decision to sell or retain a horse second we compare the effect seller characteristics have on observed prices in certified and noncertified sales our last test follows bond 1982 who attempts to identify adverse selection in the market for used trucks by comparing the repair records of trucks that were sold with the records of trucks retained by their original owners because the horses in our sample had not begun their racing careers at the time they were sold we use data on racetrack earnings as an ex post measure of quality and compare the quality of horses sold in noncertified sales with certified horses and horses retained by their breeders the results from each approach are consistent with certification alleviating problems of adverse selection we find that holding observable attributes constant horses that would receive unusually high market prices in noncertified sales are even more valuable in other options and are less likely to be sold in a noncertified sale

fair management of social risk we provide a general method for extending social preferences defined for riskless economic environments to the context of risk and uncertainty we apply the method to the problems of managing unemployment allowances in the context of macroeconomic fluctuations and catastrophic risks in the context of climate change the method guarantees ex post fairness and pays attention to individuals risk attitudes while ensuring rationality properties for social preferences revisiting basic ideas from harsanyi s celebrated aggregation theorem harsanyi 1955 the social preferences that we obtain do not always take the form of an expected utility criterion but they always satisfy statewise dominance when we require social preferences to be expected utilities we obtain a variant of harsanyi s result under a weak version of the pareto principle and a maximin criterion under a stronger pareto requirement whenever the ex post social ordering does not depend on people s risk attitudes we also show how non expected utility individual preferences can be accommodated in the approach

the big one a review of richard posner s catastrophe risk and response richard posner s catastrophe risk and response oxford university press 2004 examines four risks whose worst cases could end advanced human civilization or worse asteroid impacts a catastrophic chain reaction initiated in high energy particle accelerators global climate change and bioterrorism he argues that these all warrant more thought and response than they are receiving and that they can usefully be assessed using a simple analytic framework based on cost benefit analysis this essay reviews knowledge of these risks and critically examines posner s claims for a consistent analytic approach while the conclusions that each risk merits more thought and effort appear persuasive these rely on ad hoc arguments specific to each risk the general analytic claims do not hold up well as posner develops his proposed framework thinly and applies it unevenly applying such a framework consistently to catastrophic risks would require engaging some fundamental problems that posner does not address the book s major contributions are to identify and describe these risks highlight the inadequate attention they are receiving and advance a persuasive argument for their more serious examination

certification under oligopolistic competition in a symmetric duopolistic market where each firm s choice regarding certain quality attributes such as the environmental friendliness of its product is its own private information the extent of horizontal differentiation between firms plays a crucial role in a certifier s optimal certification policy under a non profit certifier it is always the case that both firms produce the highest quality and opt for certification this is also the case under a for profit certifier but only when the degree of horizontal differentiation is sufficiently high when horizontal differentiation is low the for profit certifier by charging a very high certification fee creates maximum vertical differentiation between firms as a result only one firm produces the highest quality and opts for certification whereas the other firm produces the lowest quality and does not opt for certification this asymmetry under a for profit certifier makes the market inefficient which provides one possible explanation for the existence of mostly non profit certifiers in such markets

the value of recommendations abstract many markets without repeated seller buyer relations feature third party monitors that sell recommendations we analyze the profit maximizing recommendation policies of such monitors in an infinitely repeated game with seller moral hazard and short lived consumers a monopolistic monitor with superior information about the seller s past effort decisions sells recommendations about the seller to consumers we show that the monitor has an incentive to make its recommendations hard to predict which in general leads to inefficient effort provision by the seller these results hold under perfect and imperfect monitoring and in a variety of informational setting when there are multiple competing sellers the conflict between the monitor s profit maximization objective and efficient effort provision is mitigated

risk adjusted gamma discounting abstract it is widely recognized that the economics of distant future events like climate change is critically dependent upon the choice of a discount rate unfortunately it is unclear how to discount distant future events when the future discount rate itself is unknown in previous work an analytically tractable approach called gamma discounting was proposed which gave a declining discount rate schedule as a simple closed form function of time this paper extends the previous gamma approach by using a ramsey optimal growth model combined with uncertainty about future productivity in order to risk adjust all probabilities by marginal utility weights some basic numerical examples are given which suggest that the overall effect of risk adjusted gamma discounting on lowering distant future discount rates may be significant the driving force is a fear factor from risk aversion to permanent productivity shocks representing catastrophic future states of the world

a model of biased intermediation this paper studies situations in which some consumers rely on a potentially biased intermediary to choose among downstream firms we introduce the notion that firms and consumers payoffs can be congruent or conflicting and show that this has important implications for the effects of bias under congruence the firm towards which the intermediary is biased invests more than its rival and consumers can be better off than under no bias under conflict bias hurts consumers and the favored firm charges higher prices we study various oft proposed policies for dealing with a biased intermediary and show that the efficacy of each intervention depends strongly on whether the environment exhibits congruence or conflict we discuss how the model relates to recent issues in online markets

an economic analysis of interest rate swaps interest rate swaps a financial innovation in recent years are based upon the principle of comparative advantage an interest rate swap is a useful tool for active liability management and for hedging against interest rate risk the purpose of this paper is to provide a simple economic analysis of interest rate swaps alternative uses of and the appropriate valuation procedure for interest rate swaps are described the significant increase in both the levels and the volatilities of market interest rates since the late 70 s has resulted in substantially higher interest rate risks faced by business firms and financial institutions the problem and consequences of interest rate risk exposure are particularly serious for firms in which the duration of assets does not match the duration of the liabilities for instance most financial institutions and many corporations financed long term fixed rate assets with short term floating rate liabilities such firms lose when the shortterm interest rates in the market rise unexpectedly because for given fixed rates of return on their assets the short term interest costs that they have to pay rise with the market interest rates conversely these firms gain from an unexpected decline in short term market interest rates in recent years the introduction and the development of new financial products in the capital markets such as interest rate futures interest rate options and interest rate swaps represent logical responses to the increased need to reduce firms exposure to interest rate risk

monetary valuation of the social cost of co2 emissions a critical survey an expanding branch of research has estimated the potential costs of climate change which are often expressed as the social cost of carbon scc or the costs of an additional ton of co2 emissions estimates of the scc can be used by policy makers to evaluate climate change policies and greenhouse gas emission reduction projects by means of cost benefit analyses cbas such analyses are complicated by the wide range of scc values that have been reported in the literature and the large uncertainties involved in estimating the potential economic impacts and related costs of climate change this study presents a critical review of the reported scc estimates by examining some neglected consequences of climate change uncertain and extreme scenarios of climate change the discounting of future climate change effects the treatment of individual risk aversion and assumptions about social welfare in view of the many uncertainties and omissions in conventional cost benefit analyses of climate impacts and the scc alternative approaches to decision making should be considered for climate policy

strategic certification and provision of quality we study the effect of the presence of a certification intermediary in an environment where information asymmetries are particularly severe the intermediary improves the information that buyers have about quality this in turn increases the incentives that the seller has to provide high quality goods efficiency is increased by the presence of the intermediary but quality is underprovided in equilibrium relative to full information the intermediary can implement the optimal policy in many ways the amount of information revealed ranges from full disclosure to partial noisy disclosure

climate policy under fat tailed risk an application of dice uncertainty plays a significant role in evaluating climate policy and fat tailed uncertainty may dominate policy advice should we make our utmost effort to prevent the arbitrarily large impacts of climate change under deep uncertainty in order to answer to this question we propose a new way of investigating the impact of fat tailed uncertainty on optimal climate policy the curvature of the optimal carbon tax against the uncertainty we find that the optimal carbon tax increases as the uncertainty about climate sensitivity increases but it does not accelerate as implied by weitzman s dismal theorem we find the same result in a wide variety of sensitivity analyses these results emphasize the importance of balancing the costs of climate change against its benefits also under deep uncertainty 2013 springer science business media dordrecht

designing climate mitigation policy this us paper provides an exhaustive review of critical issues in the design of climate mitigation policy by pulling together key findings and controversies from diverse literatures on mitigation costs damage valuation policy instrument choice technological innovation and international climate policy the authors begin with the broadest issue of how high assessments suggest the near and medium term price on greenhouse gases would need to be both under cost effective stabilization of global climate and under net benefit maximization or pigouvian emissions pricing the remainder of the paper focuses on the appropriate scope of regulation issues in policy instrument choice complementary technology policy and international policy architectures

the pricing of corporate debt a note to develop a theory of the risk structure of interest rates r c merton 2 defines the risk as the possible gains or losses to bond holders as a result of unanticipated changes in the probability of default p 449 he derives the pricing theory of a pure discount bond corporation debt along the line of blackscholes 1 comparative statics are used to develop graphs of the risk structure although his algebraic derivation is correct his graphical presentation is inadvertently wrong

designing a climate change policy for the international maritime transport sector market based measures and technological options for global and regional policy actions abstract the international maritime transport sector has a significant abatement potential and some technical improvements that reduce ghg emissions would already be profitable without any policy in place this paper analyses in depth the limits and opportunities of policy options currently under consideration at the international level to stimulate the sector to reduce its ghg emissions in particular in order for the maritime transport sector to become more environmentally friendly the flexible nature of international market based measures and the european union emission trading scheme provide a definite window of opportunity without placing unnecessary high burden on the sector however the development of a regional policy such as at european level for the international maritime transport sector faces several obstacles allocation of emissions carbon leakage permit allocation treatment of the great variety in ship type size and usage and transaction cost global market based policies could overcome most of these challenges this paper provides an in depth analysis of the policy instruments currently under discussion to reduce the sector s burden on the environment and focuses on economic theory legal principles technological options and the political framework that together make up the basis of decision making regarding the international maritime transport sector s climate change policies

a review of the stern review on the economics of climate change the stern review calls for immediate decisive action to stabilize greenhouse gases because the benefits of strong early action on climate change outweighs the costs the economic analysis supporting this conclusion consists mostly of two basic strands the first strand is a formal aggregative model that relies for its conclusions primari ly upon imposing a very low discount rate concerning this discount rate aspect i am skeptical of the review s formal analysis but this essay points out that we are actual ly a lot less sure about what interest rate should be used for discounting climate change than is commonly acknowledged the review s second basic strand is a more intuitive argument that it might be very important to avoid possibly large uncertain ties that are difficult to quantify concerning this uncertainty aspect i argue that it might be recast into sound analytical reasoning that might justify some of the review s conclusions the basic issue here is that spending money to slow global warming should perhaps not be conceptualized primarily as being about consump tion smoothing as much as being about how much insurance to buy to offset the small change of a ruinous catastrophe that is difficult to compensate by ordinary savings

quality signaling through certification in developing countries this paper studies how signaling the credence attributes of consumer goods distorts their market equilibrium in developing countries costs of certification sunk in order to achieve credibility play a key role in producing an oligopolistic market leading to high prices that form a barrier for consumers in the south to lower the cost certification is better achieved by a single independent body which can be financed either by end consumers through a fee or by public subsidies the paper identifies the conditions under which each funding mechanism is most efficient taking into account the government s budget constraint the theoretical analysis is motivated with reference to agricultural seed certification

sequential decisions with tests we consider a principal agent problem where the principal wishes to be endorsed by a sequence of agents but cannot truthfully reveal type in the standard herding model the agents learn from each other s decisions which can lead to cascades on a given decision when later agents private information is swamped we augment the standard model to allow the principal to subject herself to a test designed to provide public information about her type she must decide how tough a test to attempt from a continuum of test types which involves trading off the higher probability of passing an easier test against the greater impact from passing a tougher test we find that the principal will always choose to be tested and will prefer a tough test to a neutral or easy one

expected utility theory and the tyranny of catastrophic risks expected utility theory is not only applied to individual choices but also to ethical decisions e g in cost benefit analysis of climate change policy measures that affect future generations in this context the crucial question arises whether eu theory is able to deal with catastrophic risks i e risks of high but very unlikely losses in an ethically appealing way in this paper we show that this is not the case rather if in the framework of eu theory a plausible level of risk aversion is assumed a tyranny of catastrophic risk tcr emerges i e project evaluation may be dominated by the catastrophic event even if its probability is negligibly small with low degrees of risk aversion however the catastrophic risk eventually has no impact at all when its probability goes to zero which is ethically not acceptable as well

models as usual for unusual risks on the value of catastrophic climate change we study the role of alternative intertemporal preference representations in a model of economic growth stock pollutant and endogenous risk of catastrophic collapse we contrast the traditional discounted utility model which assumes risk neutrality with respect to intertemporal utility with a multiplicative choice model that displays risk aversion in that dimension first we show that both representations of preferences can rationalize the same business as usual economy for a given interest rate and no pollution externality second once we introduce a collapse risk whose hazard rate is a function of the pollution stock multiplicative preferences recommend a much more stringent policy response an illustration in the context of climate change indicates that switching to the multiplicative preference representation has a similar effect in terms of policy recommendations as scaling up the schedule of the hazard rate by a factor of 100

quality disclosure and certification theory and practice this essay reviews the theoretical and empirical literature on quality disclosure and certification after comparing quality disclosure with other quality assurance mechanisms and describing a brief history of quality disclosure we address two sets of theoretical issues first why don t sellers voluntarily disclose through a process of unraveling and given the lack of unraveling is it desirable to mandate seller disclosure second when we rely on certifiers to act as the intermediary of quality disclosure do certifiers necessarily report unbiased and accurate information we further review empirical evidence on these issues with a particular focus on healthcare education and finance the empirical review covers quality measurement the effect of third party disclosure on consumer choice and seller behavior as well as the economics of certifiers jel d18 k32 l15 m31

on the valuation of long dated assets i show that the pricing of a broad class of long dated assets is driven by the possibility of extraordinarily bad news this result does not depend on any assumptions about the existence of disasters nor does it apply only to assets that hedge bad outcomes indeed it applies even to long dated claims on the market in a lognormal world if the market s sharpe ratio is higher than its volatility as appears to be the case in practice

the value of life and the rise in health spending over the past half century americans spent a rising share of total economic resources on health and enjoyed substantially longer lives as a result debate on health policy often focuses on limiting the growth of health spending we investigate an issue central to this debate is the growth of health spending a rational response to changing economic conditions notably the growth of income per person we develop a model based on standard economic assumptions and argue that this is indeed the case standard preferences of the kind used widely in economics to study consumption asset pricing and labor supply imply that health spending is a superior good with an income elasticity well above one as people get richer and consumption rises the marginal utility of consumption falls rapidly spending on health to extend life allows individuals to purchase additional periods of utility the marginal utility of life extension does not decline as a result the optimal composition of total spending shifts toward health and the health share grows along with income in projections based on the quantitative analysis of our model the optimal health share of spending seems likely to exceed 30 percent by the middle of the century

communicating trade offs amid controversial science decision support for climate policy abstract the paper considers the decision that arises in climate policy where there is expert disagreement about the correct scientific model and where a group of stakeholders needs to agree on a common policy target policy choice is posed as a decision under knightian uncertainty where decision makers lack grounds for assigning a particular probability distribution across contending forecasting models the decision is then framed as one of balancing two competing objectives that plausibly align with the dominant concern of stakeholders from each side in the policy debate a decision criterion is proposed to identify options for compromise that balance these objectives in different ways the criterion spans three standard non bayesian decision criteria policies generated by the criterion are combined with visual tools to communicate what s at stake in an environmental policy decision in which stakeholders disagree both about scientific models and about the relative importance of risks to the environment versus risks to economic growth the approach summarizes information that could be useful to policy makers tasked with negotiating a compromise the framework is applied to climate policy using dice 2007 nordhaus 2008 the results highlight a basic asymmetry between the mistake of doing too little and that of doing too much that suggests a strong argument for avoiding the current status quo of global inaction

a quantitative minimax regret approach to climate change does discounting still matter abstract using cost benefit analysis to determine an optimal climate mitigation target is criticised especially because i it fails to sufficiently take into account low probability high impact events and ii results strongly depend on the discount rate used one of the alternative suggestions to inform policymakers about the right mitigation target that does take the risks associated with low probability high impact events explicitly into account is the minimax regret criterion we apply the minimax regret criterion quantitatively using an integrated assessment model with extreme values for climate sensitivity damage estimates and mitigation costs the goal is to analyse whether such a method leads to different results compared to standard cost benefit analysis and whether the results are still sensitive to the discount rate used we find that the minimax regret approach leads to more stringent and robust climate targets for relatively low discount rates and if both a high climate sensitivity and high damage estimates are assumed if one of these assumptions does not hold the difference between the minimax regret approach and standard cost benefit analysis is much smaller therefore we conclude that the discount rate used can still be of vital importance even when applying a minimax regret approach

are energy efficiency standards justified abstract this paper develops an analytical framework for comparing the welfare effects of energy efficiency standards and pricing policies for reducing gasoline electricity and nationwide carbon emissions the model is parameterized with us data and includes key externalities in the energy transportation sectors and possible underinvestment in energy efficiency due to misperceptions over energy savings even with large misperceptions the extra welfare gains from complementing efficient pricing policies with energy efficiency standards are zero for reducing gasoline and 5 percent for reducing electricity and when viewed as substitutes these standards forgo 60 percent or more of the potential welfare gains from corresponding pricing policies a combination of energy efficiency and emissions standards is more than three times as costly as carbon pricing when there is no misperception over energy savings and even with large misperceptions combining carbon pricing with gasoline electricity taxes is better than combining it with energy efficiency standards

certification and minimum quality standards when some consumers are uninformed we compare certification to a minimum quality standard mqs policy in a duopolistic industry where firms incur quality dependent fixed costs and only a fraction of consumers observe the quality of the offered goods compared to the unregulated outcome both profits and social welfare would increase if firms could commit to producing a higher quality an mqs restricts the firms quality choice and leads to less differentiated goods this fuels competition and may therefore deter entry a certification policy which awards firms with a certificate if the quality of their products exceeds some threshold does not restrict the firms quality choice in contrast to an mqs certification may lead to more differentiated goods and higher profits we find that firms are willing to comply with an ambitious certification standard if the share of informed consumers is small in that case certification is more effective from a welfare perspective than a minimum quality standard because it is less detrimental to entry

climate policy under sustainable discounted utilitarianism empirical evaluation of policies to mitigate climate change has been largely confined to the application of discounted utilitarianism du du is controversial both due to the conditions through which it is justified and due to its consequences for climate policies where the discounting of future utility gains from present abatement efforts makes it harder for such measures to justify their present costs in this paper we propose sustainable discounted utilitarianism sdu as an alternative principle for evaluation of climate policy unlike undiscounted utilitarianism which always assigns zero relative weight to present utility sdu is an axiomatically based criterion which departs from du by assigning zero weight to present utility if and only if the present is better off than the future using the dice integrated assessment model to run risk analysis we show that it is possible for the future to be worse off than the present along a business as usual development path consequently sdu and du differ and willingness to pay for emissions reductions is sometimes significantly higher under sdu than under du under sdu stringent schedules of emissions reductions increase social welfare even for a relatively high utility discount rate

borrowing cost reduction by interest rate swaps an option pricing analysis abstract interest rate swaps generally involve two firms with different credit ratings a quality spread differential qsd is observed to exist at different maturities for firm debts with different credit ratings the quality spread differential allows two firms with different credit ratings to decrease their borrowing costs through interest rate swaps by utilising their comparative advantage in borrowing in different markets the credit ratings of firms are determined by credit risk factors such as leverage and volatility of earnings asset value this paper investigates the effect of the leverage and the volatility on the behaviour of risk premia between firm debts with different credit ratings by using the contingent claim analysis our results show that the quality spread differential can be explained by the differences in leverage and volatility thus two firms with different leverage and volatility of earnings asset value will benefit from interest rate swaps however it is found that the duration within which the qsd exists is limited by the values of the leverage and the volatility of two firms in conclusion this paper shows that interest rate swaps can help the firms to lower borrowing costs without necessarily relying on the arbitrage argument asserted by existing literature

a note on some limitations of crra utility abstract in a standard environment for choice under uncertainty with constant relative risk aversion crra the existence of expected utility is fragile with respect to changes in the distributions of random variables changes in prior information or the assumption of rational expectations

a review of the stern review on the economics of climate change how much and how fast should we react to the threat of global warming the stern review argues that the damages from climate change are large and that nations should undertake sharp and immediate reductions in greenhouse gas emissions an examination of the review s radical revision of the economics of climate change finds however that it depends decisively on the assumption of a near zero time discount rate combined with a specific utility function the review s unambiguous conclusions about the need for extreme immediate action will not survive the substitution of assumptions that are consistent with today s marketplace real interest rates and savings rates

uncertainty learning and international environmental agreements the role of risk aversion this paper analyses the formation of international environmental agreements ieas under uncertainty learning and risk aversion it bridges two strands of the iea literature i the role of learning when countries are risk neutral ii the role of risk aversion under no learning combining learning and risk aversion seems appropriate as the uncertainties surrounding many international environmental problems are large often highly correlated e g climate change but are gradually reduced over time through learning the paper analyses three scenarios of learning a key finding is that risk aversion can change the ranking of these three scenarios of learning in terms of welfare and membership in particular the negative conclusion about the role of learning in a strategic context under risk neutrality is qualified when countries are significantly risk averse then it pays them to wait until uncertainties have been largely resolved before joining an iea this may suggest why it has been so difficult to reach an effective climate change agreement

honest certification and the threat of capture abstract this paper derives conditions under which reputation enables certifiers to resist capture these conditions alone have strong implications for the industrial organization of certification markets 1 honest certification requires high prices that may even exceed the static monopoly price 2 honest certification exhibits economies of scale and constitutes a natural monopoly 3 price competition tends to a monopolization the results derive from a general principle of reputation models that favors concentration this principle implies benefits from specialization and explains specialized certifiers as efficient market institutions that sell reputation as a service to other firms

on modeling and interpreting the economics of catastrophic climate change with climate change as prototype example this paper analyzes the implications of structural uncertainty for the economics of low probability high impact catastrophes even when updated by bayesian learning uncertain structural parameters induce a critical tail fattening of posterior predictive distributions such fattened tails have strong im plications for situations like climate change where a catastrophe is theoretically possible because prior knowledge cannot place sufficiently narrow bounds on overall damages this paper shows that the economic consequences of fat tailed structural uncertainty along with unsureness about high temperature damages can readily outweigh the effects of discounting in climate change policy analysis

economics and climate change integrated assessment in a multi region world 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 bad approximation of reality its major advantage is that along with a set of reasonable assumptions on preferences technology and nature it allows a closed form model solution we use the model to assess the welfare consequences of carbon taxes that differ across as well as within oil consuming and producing regions we show that surprisingly only taxes on oil producers can improve the climate taxes on oil consumers have no effect at all the calibrated model suggests large differences in views on climate policy across regions

the incredible economics of geoengineering the focus of climate policy so far has been on reducing the accumulation of greenhouse gases that approach however requires broad international cooperation and being expensive has been hindered by free riding so far little action has been taken an alternative approach is to counteract climate change by reducing the amount of solar radiation that strikes the earth geoengineering in contrast to emission reductions this approach is inexpensive and can be undertaken by a single country unilaterally but geoengineering also has worrying consequences it may harm some countries it would not address ocean acidification it would pose new risks the fundamental challenge posed by this new technology is not free riding but governance who should decide if and under what circumstances geoengineering should be used