environmental protection rare disasters and discount rates the stern review s evaluation of environmental protection stresses low discount rates and uncertainty about environmental effects an appropriate model for analysing this uncertainty and the associated discount rates requires sufficient risk aversion and fat tailed uncertainty to account for the observed equity premium calibrations based on epstein zin preferences and existing analyses of rare macroeconomic disasters suggest that optimal environmental investment can be a significant share of gdp even with reasonable rates of time preference optimal environmental investment increases with risk aversion and the probability and typical size of environmental disasters but decreases with uncertainty about policy effectiveness

perception theoretic foundations of weighted utilitarianism we provide a microfoundation for a weighted utilitarian social welfare function that reflects common moral intuitions about interpersonal comparisons of utilities if utility is only ordinal in the usual microeconomic sense interpersonal comparisons are meaningless nonetheless economics often adopt utilitarian welfare functions assuming that comparable utility functions can be calibrated using information beyond consumer choice data we show that consumer choice data alone are sufficient as suggested by edgeworth 1881 just noticeable differences jnds provide a common unit of measure for interpersonal comparisons of utility differences we prove that a simple monotonicity axiom implies a weighted utilitarian aggregation of preferences with weights proportional to individual jnds

willingness to pay and the distribution of risk and wealth willingness to pay wtp most economists believe is an appropriate benefits metric for government expenditure and regulatory policies that reduce risks to human life it depends however on the distribution of risk and wealth currently society s expenditures overemphasize concentrated risks say after the fact treatment as opposed to prevention a dead anyway effect complements excess attention to intense interests in explaining this our normative criterion for spending on risk reduction is what a rational albeit uninsured individual confronting lotteries on future risks to life and wealth would choose for himself this requires correcting wtp to eliminate the dead anyway effect but continues to reflect that wealth enhances the utility of living

equity axioms for public risks from the perspective of a two person society we explain and analyze six axioms for equity among individuals who are exposed to the possibility of death from a public hazard the axioms are concerned with how a given total risk expected fatalities is distributed over the four possible life death consequences for the two people maximal subsets of mutually compatible equity axioms are identified first for a monotonic ordinal utility function and then for a more restrictive von neumann morgenstern utility function

utilitarianism egalitarianism and the timing effect in social choice problems two theorems are derived about social choice functions which are defined on comprehensive convex subsets of utility allocation space theorem 1 asserts that a linearity condition together with pareto optimality implies that a social choice function must be utilitarian theorem 2 asserts that a concavity condition together with pareto optimality and independence of irrelevant alternatives implies that a social choice function must be either utilitarian or egalitarian these linearity and concavity conditions have natural interpretations in terms of the timing of social welfare analysis before or after the resolution of uncertainties and its impact on social choices

regulation in happyville how does risk perception affect risk regulation happyville is a society in which citizens wrongly believe that the drinking water supply is contaminated we discuss conditions under which a benevolent director of environment protection would invest in a water cleanup technology this holds if the director is populist namely if he maximises social welfare based on citizens pessimistic beliefs more surprisingly investment in the water cleanup technology may occur if the director is paternalistic in the sense that he maximises social welfare based on his own beliefs the reason is that he must take into account citizens responses to regulation

bliss catastrophe and rational policy lotteries with infinite expected utility are inconsistent with the axioms of expected utility theory to rule them out either the set of permissible lotteries must be restricted to exclude at a minimum fat tailed distributions such as that underlying the st petersburg paradox and power laws that are popular in models of climate change or the utility function must be bounded this note explores the second approach and proposes a number of tractable specifications leading to utility functions that are bounded both from above and below this property is intimately related to that of increasing relative risk aversion as first hypothesized by arrow 1965

betrayal aversion evidence from brazil china oman switzerland turkey and the united states comment in a series of binary choice problems we investigate how a chooser s risk taking changes when others share in their personal risk either equally or unequally we find that when the safe option yields inequality the risky option is taken significantly more often on the other hand the inequality resulting from the risky choice does not affect risk taking we also find that choosers tend to be less risk averse in a one person context compared to when the risk also affects the payoff of another c72 d81 z13

cost benefit analysis under uncertainty a note on weitzman s dismal theorem abstract weitzman s 2009 famous dismal theorem argues that fat tails in the distribution of warming may pose problems for cost benefit analysis as it may imply that society might be willing to exchange today s consumption for future consumption at an infinite rate his analysis is based on the stochastic discount factor we show that in situations in which the stochastic discount factor is applicable it is optimal for society to devote only a finite amount of resources to protect against climate change for general assumptions on the investment returns cost benefit analysis must consider the joint distribution of the marginal utility of future consumption and marginal returns to investment in the different future states of nature we explore the range of situations under which challenges for applying cost benefit analysis under uncertainty remain

distributive justice for behavioural welfare economics the incompleteness of behavioural preferences can lead many or even all allocations to qualify as pareto optimal but the incompleteness does not undercut the precision of utilitarian policy recommendations utilitarian methods can be applied to groups of goods or to the multiple social welfare functions that arise when individual preferences are incomplete and policymakers do not need to provide the preference comparisons that individuals are unable to make for themselves the utilitarian orderings that result although also incomplete can generate a unique optimum non separabilities in consumption reduce this precision but in all cases the dimension of the utilitarian optima drops substantially relative to the pareto optima

let s agree that all dictatorships are equally bad this paper shows that a minimal degree of consideration for other people s well being enables society to agree that one social policy is the best i offer axioms that imply that this best policy maximizes a weighted sum of individual utilities the weight of each individual is the inverse of his or her maximal possible utility from social endowments the suggested policy is not sensitive to the choice of the von neumann morgenstern utilities the key axiom is that individuals agree that giving all the endowments always to one person is as bad as giving them to any other person

news droughts news floods and u s disaster relief this paper studies the influence of mass media on u s government response to approximately 5 000 natural disasters occurring between 1968 and 2002 these disasters took nearly 63 000 lives and affected 125 million people per year we show that u s relief depends on whether the disaster occurs at the same time as other newsworthy events such as the olympic games which are obviously unrelated to need we argue that the only plausible explanation of this is that relief decisions are driven by news coverage of disasters and that the other newsworthy material crowds out this news coverage

an empirical analysis of the reincorporation decision the literature suggests two competing explanations for reincorporations efforts at managerial entrenchment and attempts to improve contractual efficiency the empirical evidence to date is inconclusive to seek further evidence we examine a large sample of firms that changed their state of incorporation over the period 1980 1992 we find that shareholder wealth is decreased by reincorporations that erect takeover defenses but is increased by reincorporations that establish limits on director liability firms that claim they reincorporate to limit the personal liability of their board members and thereby attract better qualified outside directors do in fact expand the outside representation on their boards whereas firms citing other motives do not

stock dividends stock splits and signaling this paper provides evidence that firms signal their private information about future earnings by their choice of split factor split factors are increasing in earnings forecast errors after controlling for differences in pre split price and firm size furthermore price changes at stock dividend and split announcements are significantly correlated with split factors holding other factors constant and with earnings forecast errors these correlations suggest that management s choice of split factor signals private information about future earnings and that investors revise their beliefs about firm value accordingly the analysis also suggests however that announcement returns are significantly correlated with split factors after controlling for earnings forecast errors this suggests that earnings forecast errors measure management s private information about future earnings with error that split factors signal other valuation relevant attributes or that a signaling explanation is incomplete researchers have long puzzled over the role of stock splits and stock dividends a stock dividend or split increases the number of equity shares outstanding but has no effect on shareholders proportional ownership of shares it is therefore puzzling that firms engage in these transactions and even more so that stock prices rise on average when these transactions are announced as grinblatt masulis and titman 1984 document the significant positive announcement effects led grinblatt masulis and titman hereafter gmt to hypothesize that firms signal information about their future earnings or equity values through their split decisions to date this hypothesis has met with limited support gmt conclude that the announcement returns cannot be explained by forecasts of imminent increases in cash dividends because they observe similar stock price behavior in firms that do not pay dividends our study provides further evidence on the signaling hypothesis by testing whether stock dividends and splits convey information about future earnings and by testing whether the split factor itself is the signal the notion that the split factor may act as a signal has institutional as well as theoretical support practitioners have long contended that the purpose of stock splits is to move a firm s share price into an optimal trading range baker and gallagher 1980 who surveyed chief financial officers of firms that split their shares report that 94 of their sample indicated their stock splits moved their

attitudes toward catastrophe in light of climate change and other global threats policy commentators sometimes urge that society should be more concerned about catastrophes this paper reflects on what society s attitude toward low probability high impact events is or should be we first argue that catastrophe risk can be conceived of as a spread in the distribution of losses based on this conception we review studies from decision sciences psychology and behavioral economics that explore people s attitudes toward various social risks contray to popular belief we find more evidence against than in favor of catastrophe aversion the preference for a mean preserving contraction of the loss distribution and discuss a number of possible behavioral explanations next we turn to social choice theory and examine how various social welfare functions handle catastrophe risk we explain why catastrophe aversion may be in conflict with equity concerns and other regarding preferences finally we discuss current approaches to evaluate and regulate catastrophe risk

guilt in games a clear conscience is a good pillow why does this old proverb contain an insight the emotion of guilt holds a key psychologists report that the prototypical cause of guilt would be the infliction of harm loss or distress on a relationship partner roy baumeister arlene m stillwell and todd f heatherton 1994 245 june price tangney 1995 moreover guilt is unpleasant and may affect behavior to render the associated pangs counterfactual baumeister stillwell and heatherton state if people feel guilt for hurting their partners and for failing to live up to their expectations they will alter their behavior to avoid guilt in ways that seem likely to maintain and strengthen the relationship avoided guilt is the down of the sound sleeper s bolster how can guilt be modeled how are human interaction and economic outcomes influenced we offer a formal approach for providing answers start with an extensive game form which associates a monetary outcome with each end node say that player i lets player j down if as a result of i s choice of strategy j gets a lower monetary payoff than j expected to get before play started player i s guilt may depend on how much he lets j down player i s guilt may also depend on how much j believes i believes he lets j down we develop techniques to analyze equilibria when players are motivated in part by a desire to avoid guilt the intellectual home for our exercise is what has been called psychological game theory this framework originally developed by john geanakoplos david pearce and ennio stacchetti 1989 and recently extended by battigalli and dufwenberg 2005 henceforth b d allows players utilities to depend on beliefs about choices states of nature

the market reaction to the choice of accounting method for stock splits and large stock dividends prior research has used inaccurate classification rules to distinguish between stock splits and stock dividends the crsp classification of two for one stock distributions agrees with the actual accounting treatment only 23 of the time in addition the accounting treatment impacts the announcement period reaction two for one distributions accounted for as stock dividends are associated with five day announcement period returns of 2 70 significantly greater that the 0 93 announcement returns for distributions accounted for as stock splits announcement returns are positively related to earnings growth in the two years following the distribution for stock dividend firms but not for stock split firms the accounting choice appears to be used to confirm management s private information about future earnings revealed at the time of the distribution announcement

signaling managerial optimism through stock dividends and stock splits a reexamination of the retained earnings hypothesis the retained earnings hypothesis predicts that stock distributions accounted for by reducing retained earnings are a more credible signal of managerial optimism than stock distributions that do not reduce retained earnings this study examines the costs of false signaling that are a necessary precondition for the hypothesis and finds them to be generally very small the absence of the requisite costs of false signaling calls the validity of the hypothesis into question for most firms however prior studies have reported broad based market evidence consistent with the retained earnings hypothesis to resolve this apparent inconsistency this study replicates and extends tests of the retained earnings hypothesis contained in three prior studies it shows that the findings in support of the retained earnings hypothesis can be attributed to specification and measurement choices that bias the results in favor of the hypothesis the support for the retained earnings hypothesis is weaker when the sources of the bias are removed however some support for the hypothesis remains for a limited set of distributing firms

generalized social marginal welfare weights for optimal tax theory this paper proposes to evaluate tax reforms by aggregating money metric losses and gains of different individuals using generalized social marginal welfare weights optimum tax formulas take the same form as standard welfarist tax formulas by simply substitut ing standard marginal social welfare weights with those generalized weights weights directly capture society s concerns for fairness without being necessarily tied to individual utilities suitable weights can help reconcile discrepancies between the welfarist approach and actual tax practice as well as unify in an operational way the most prominent alternatives to utilitarianism such as libertarianism equality of opportunity or poverty alleviation jel d60 d63 h21 h23 i38

the effect of risk characteristics on the willingness to pay for mortality risk reductions from electric power generation the objective of this study is to estimate willingness to pay wtp for the reduction of mortality risks caused by fossil fuel natural gas coal and oil versus nuclear electric power generation systems and to examine the influence of risk characteristics involved with electric power generation on wtp a choice experiment was conducted to achieve these objectives the attributes for nuclear risks in the experiment included the probability of disasters and the expected losses if a disaster occurs we find evidence of i a baseline effect where wtp is sensitive to hypothetical versus actual baseline expected mortality ii a labeling effect where surprisingly the term nuclear has no effect on wtp but the term fossil fueled power generation results in lower wtp and iii disaster aversion meaning that people focus on the conditional loss from a nuclear disaster not the probability we also find that the wtp for reducing deaths from a nuclear disaster is about 60 times the wtp for routine reducing fossil fuel generation related deaths