a behavioral framework for time diversification the box of factors that we call risk is both too large and too small the box is large enough to include many sometimes conflicting measures of risk variance and semivariance probabilities of losses and their amounts but the box is too small to include factors that affect choices but fall outside the boundaries of risk frames and cognitive errors self control and regret we explore the role of these factors in time diversification the belief that time diversification reduces risk underlies the current drive to invest social security funds in stocks but is such investment prudent we discuss the role of advisors in providing prudent advice changes in the standards of prudence over time the use of time diversification in guiding investors to prudent portfolios and its use in the current debate on social security

information advantage in cournot oligopoly abstract consider an oligopolistic industry where firms have access to the same technology but are asymmetrically informed about the environment even though it is commonplace to think that in this context superior information leads to higher profits we find that under cournot competition this is not generally the case it holds when firms technology exhibits constant returns to scale but it does not necessarily hold otherwise journal of economic literature classification numbers c72 d43 l13

the influence of probability on risky choice a parametric examination abstract the appeal of expected utility theory as a basis for a descriptive model of risky decision making has diminished as a result of empirical evidence which suggests that individuals do not behave in a manner consistent with the prescriptive tenets of eut in this paper we explore the influence of probability on risky choice by proposing and estimating a parametric model of risky decision making our results suggest that models which provide for probability transformations are most appropriate for the majority of subjects further we find that the transformation differs for most subjects depending upon whether the risky outcomes are gains or losses most subjects are considerably less sensitive to changes in mid range probability than is proposed by the expected utility model and risk seeking behavior over long shot odds is common

performance evaluation of optimized portfolio insurance strategies abstract we use s p 500 index return data for the time period 1985 2013 to evaluate the performance of portfolio insurance strategies we shed light on the question if the performance of a constant proportion portfolio insurance cppi strategy can be improved by means of a time varying multiplier which depends on the estimated future volatility neglecting any inter temporal hedging demand the theoretical foundation of the strategies is given by maximizing the expected utility of a hara investor in a diffusion model setup if the risk premium is assumed to be proportional to the variance the optimal strategy is a cppi strategy otherwise the multiple is time varying ppi it turns out that even time varying multiple strategies based on a rolling window of historical volatility estimates give a significant improvement of cppi strategies the out performance is robust w r t alternative performance measures and is also true for proportional transaction costs and adequate trigger trading

the optimal level of social security benefits the optimal level of social security benefits depends on balancing the protection that these benefits offer to those who lack the foresight to provide for their own old age against the welfare costs of distorting economic behavior the primary such cost is the distortion in private saving the present paper derives the level of social security benefits that is optimal in three basic cases in the first section the paper derives the optimal level of benefits for an economy in which all individuals do not anticipate retirement at all and therefore do no saving the second and third sections then derive optimal benefits for two different definitions of incomplete myopia

benchmarking portfolio insurance and technical analysis a monte carlo comparison of dynamic strategies of asset allocation abstract this paper makes an extensive simulation comparison of popular dynamic strategies of asset allocation for each strategy alternative measures have been calculated for risk return and risk adjusted performance sharpe ratio sortino ratio return at risk moreover the strategies are compared in different market situations bull bear no trend markets and with different market volatility taking into account transaction costs and discrete rebalancing of portfolios the simulations show a dominant role of constant proportion strategies in bear and no trend markets and a preference for benchmarking strategies in bull markets these results are independent of the volatility level and the risk adjusted measure adopted

decision making under uncertainty a field study of cumulative prospect theory abstract the presented research tests cumulative prospect theory cpt kahneman d tversky a 1979 prospect theory an analysis of decision under risk econometrica 47 263 291 tversky a kahneman d 1981 the framing of decisions and the psychology of choice science 211 453 480 in the financial market using us stock option data option prices possess information about actual investors preferences in such a way that an exploitation of conventional option analysis along with theoretical relationships makes it possible to elicit investor preferences the option data in this study serve for estimating the two essential elements of the cpt namely the value function and the probability weighting function the main part of the work focuses on the functions simultaneous estimation under cpt original parametric specification the shape of the estimated functions is found to be in line with theory comparing to results of laboratory experiments the estimated functions are closer to linearity and loss aversion is less pronounced

option replication in discrete time with transaction costs option replication is discussed in a discrete time framework with transaction costs the model represents an extension of the cox ross rubinstein binomial option pricing model to cover the case of proportional transaction costs the method proceeds by constructing the appropriate replicating portfolio at each trading interval numerical values of these prices are presented for a range of parameter values the paper derives a simple black scholes type approximation for the option prices with transaction costs and demonstrates numerically that it is quite accurate for plausible parameter values

national and international privatisation of pensions abstract the paper analyses the switch from pay as you go to funded pensions pensions privatisation in a world with many small open economies it contrasts go it alone privatisation in one country with world wide privatisation in the go it alone case at least one generation necessarily loses in the world wide case the long run gains are substantially larger and depending on the nature of production technology an intergenerational pareto improvement is possible this generates a potential isolation paradox each country may individually reject privatisation because some people will lose but this need not happen if all privatised simultaneously this problem occurs because the adoption of payg pensions in any one country imposes international externalities on other countries via the impact on world interest rates

improving nash by coarse correlation we consider a class of symmetric two person quadratic games where coarse correlated equilibria cce moulin and vial 1978 can strictly improve upon the nash equilibrium payoffs while correlated equilibrium ce aumann 1974 1987 cannot because these games are potential games with concave potential functions we compute the largest feasible total utility in any cce in those games and show that it is achieved by a cce involving only two pure strategy profiles applications include the cournot duopoly and the game of public good provision where the improvement over and above the nash equilibrium payoff can be substantial

communication in cournot oligopoly abstract this paper studies communication in a static cournot duopoly model under the assumption that the firms have unverifiable private information about their costs we investigate the conditions under which the firms cannot transmit any information through cheap talk and show that when these conditions are violated it may be possible to construct informative cheap talk equilibria if the firms can communicate through a third party communication can be informative even when informative cheap talk is impossible we exhibit a simple mediated mechanism that ensures informative communication and interim pareto dominates the uninformative equilibrium for the firms

consistent testing for stochastic dominance under general sampling schemes we propose a procedure for estimating the critical values of the extended kolmogorov smirnov tests of stochastic dominance of arbitrary order in the general k prospect case we allow for the observations to be serially dependent and for the first time we can accommodate general dependence amongst the prospects which are to be ranked also the prospects may be the residuals from certain conditional models opening the way for conditional ranking we also propose a test of prospect stochastic dominance our method is based on subsampling and we show that the resulting tests are consistent and powerful against some n 1 2 local alternatives we also propose some heuristic methods for selecting subsample size and demonstrate in simulations that they perform reasonably we describe an alternative method for obtaining critical values based on recentring the test statistic and using full sample bootstrap methods we compare the two methods in theory and in practice

replicating options with positions in stock and cash in most situations of practical relevance the price behavior of a call option is very similar to a combined position involving the underlying stock and borrowing the call price and the stock price will change in the same direction the effect on the call price of a one dollar change in the stock price however will depend on the current price of the stock the number of shares of stock in the replicating portfolio must equal the slope of the call price curve at that price when the call is deep out of the money i e when the stock price is much lower than the striking price a one dollar change in the stock price has little effect on the call price when the stock price is equal to the striking price a one dollar change in the stock price produces roughly a half dollar change in the call price if the stock price rises until the call is deep in the money a one dollar move in the stock price results in nearly a one dollar move in the call price because the call price behaves this way we must revise

investment horizon and the attractiveness of investment strategies a behavioral approach we analyze the attractiveness of investment strategies over a variety of investment horizons from the viewpoint of an investor with preferences described by cumulative prospect theory cpt currently the most prominent descriptive theory for decision making under uncertainty a bootstrap technique is applied using historical return data of 1926 2008 to allow for variety in investors preferences we conduct several sensitivity analyses and further provide robustness checks for the results in addition we analyze the attractiveness of the investment strategies based on a set of experimentally elicited preference parameters our study reveals that strategy attractiveness substantially depends on the investment horizon while for almost every preference parameter combination a bond strategy is preferred for the short run stocks show an outperformance for longer horizons portfolio insurance turns out to be attractive for almost every investment horizon interestingly we find probability weighting to be a driving factor for insurance strategies attractiveness

the missing piece in policy analysis social security reform this lecture discusses the economic losses that result from an unfunded social security retirement system and the potential gain from shifting to a funded system the social security payroll tax distorts labor supply and the form in which compensation is paid although each individual s benefits are linked to that individual s previous payroll tax payments the low equilibrium rate of return inherent in an unfunded system implies a net payroll tax that causes distortions the resulting deadweight loss is 1 of each year s gdp in perpetuity an amount equal to 20 of payroll tax revenue and a 50 increase in deadweight loss of the personal income tax also there is the loss of investment income resulting from forcing employees to accept the low implicit return of an unfunded program rather than the much higher return paid on private saving or in a funded social security program the present value of the annual losses from using an unfunded system exceeds the benefit to those who received windfall transfers when the program began and when it expanded shifting to a funded program cannot reverse the crowding out of capital that has already occurred recognizing the existing unfunded obligation only makes that piece of the national debt explicit but shifting to a funded program limits crowding out of capital formation to the amount that already occurred future increases in annual saving that result from economic growth are able to earn the higher rate of return on real capital the present value of these gains is equivalent to a perpetuity of more than 2 of gdp a year the combi nation of improved labor market incentives and higher real return on saving has a net present value gain of more than 15 trillion an amount equivalent to three percent of each future year s gdp forever this abstract was borrowed from another version of this item

inefficient dynamic portfolio strategies or how to throw away a million dollars in the stock market a number of portfolio strategies followed by practitioners are dominated because they are incompletely diversified over time the payoff distribution pricing model is used to compute the cost of following undiversified strategies simple numerical examples illustrate the technique and computer generated examples provide realistic estimates of the cost of some typical policies using reasonable parameter values the cost can be substantial and should not be ignored by practitioners a section on generalizations shows how to extend the analysis to term structure models and other general models of returns this abstract was borrowed from another version of this item

welfare effects of unfunded pension systems when labor supply is endogenous abstract a mandatory unfunded pension system can lead to welfare losses if the contributions are levied in such a way that the labor supply decision of the individuals is distorted this is shown in an overlapping generations model for a closed economy furthermore it is shown that under certain conditions a gradual abolition of unfuded pensions using lump sum contributions in the transition phase can lead to an intergenerational pareto improvement thus the paper extends a result recently derived by homburg for a small open economy to the closed economy case

retail banking and behavioral financial engineering the case of structured products abstract we apply cumulative prospect theory and hedonic framing to evaluate discount reverse convertibles drcs and reverse convertible bonds rcbs as important examples of structured products from a boundedly rational investor s point of view while common expected utility theory would also conclude that drcs and rcbs are of interest to investors with moderate return expectations and underestimated stock return volatility that theory would overestimate the market success of drcs and underestimate that of rcbs in comparison to a situation with bounded rationality hedonic framing and relatively low subjectively felt competence levels of investors are decisive for the demand for rcbs

how loss averse are investors in financial markets abstract we investigate loss aversion in financial markets using a typical asset allocation problem our theoretical and empirical results show that investors in financial markets are more loss averse than assumed in the literature moreover loss aversion changes depending on market conditions investors become far more loss averse during bull markets than during bear markets indicating their more profound disutility for losses when others enjoy gains contrary to most previous results we find that investors are more sensitive to changes in losses than changes in gains

explaining saving investment correlations national saving and investment rates are highly positively correlated in virtually all countries this is puzzling as it apparently implies a low degree of international capital mobility this paper shows that the observed positive correlation between national saving and investment rates arises naturally within a quantitatively restricted equilibrium model with perfect mobility of financial and physical capital the model is consistent with the fact that saving investment correlations are larger for larger countries but are still substantial for small countries further the model is consistent with the finding that current account deficits tend to be associated with investment booms copyright 1993 by american economic association

optimal investment and consumption when allowing terminal debt we analyze a dynamic optimization problem which involves the consumption and investment of an investor with constant relative risk aversion for consumption but with a risk aversion for final wealth which does not necessarily imply that terminal wealth must always be positive we require risk aversion for terminal wealth to be positive but not monotone there is a point of maximal risk aversion at zero wealth and the investor may continue to consume when wealth is negative using dual optimization methods we can derive explicit solutions and we find that the optimal solution differs in a fundamental way from the case where risk aversion is monotone it turns out that the optimal consumption function is convex and concave at different wealth levels and that the optimal investment strategy may no longer be monotone as a function of the remaining time to invest and consume

social security national policies with international implications social security policies within individual countries are determined independently by national governments but the resulting outcome is inefficient compared with what would result from the international co ordination of policies this is because national social security policies produce international externalities via their effects on world interest rates an illustrative example suggests that the gains from co ordination are potentially significant virtually all countries operate social security or redistributive policies each chooses policies independently and to my knowledge no one either in a policymaking context or in the large literature on international policy co ordination has suggested that such decisions would benefit from international coordination 1 however a simple argument suggests that independent national social security policies are inefficient more specifically in the long run national governments make policy decisions which are too egalitarian this holds provided that social security lowers national saving in this case each national government faces a trade off between income redistribution and national saving and can be assumed to locate at the nationally optimal point on this trade off taking as given the world interest rate the latter is clearly not independent of the combined effect of all countries policies however if all countries expand social security the resulting fall in world saving will raise the world interest rate with adverse consequences for each national economy each country rationally ignores its own small contribution to the global outcome if this international externality were internalised by co ordination countries would relocate on the trade off between income redistribution and national saving demonstrating the existence of an externality says nothing about its quantitative significance i address this with an example which focuses on pay as you go payg retirement pensions in an economy with a mixture of forward looking and myopic individuals the pensions prevent destitution among retired myopes and thus effectively redistribute life time welfare but they also lower saving because of payg financing for all parameter values considered international co ordination of pensions policy decisions generates welfare gains which are larger for many parameter values substantially larger than recent estimates of the welfare gains from either the entire elimination of all cyclical fluctuations or the reduction of inflation and nominal interest rates from suboptimally high to optimal levels hence the issues addressed in the paper are quantitatively significant when judged against other frequently advocated i am grateful to two anonymous referees for helpful comments on earlier versions they are not responsible for the present version

from boom til bust how loss aversion affects asset prices this article studies the impact of heterogeneous loss averse investors on asset prices in very good states loss averse investors become gradually less risk averse as wealth rises above their reference point pushing up equity prices when wealth drops below the reference point the investors become risk seeking and demand for stocks increases drastically eventually leading to a forced sell off and stock market bust in bad states heterogeneity in reference points and initial wealth of the loss averse investors does not change the salient features of the equilibrium price process such as a relatively high equity premium high volatility and counter cyclical changes in the equity premium

a utility and cpt based comparison of life insurance contracts with guarantees abstract some recent literature studies whether contracts including financial guarantees can be preferred by a utility maximizing investor the main result for contracts exposed solely to financial risk e g doskeland and nordahl 2008 dichtl and drobetz 2011 is that expected utility theory eut fails to interpret demand for guarantees while cumulative prospect theory cpt is able to support the demand while the development of the financial market has a significant impact on the portfolio choice some other non financial risk might play an important role too in the present paper we take life insurance products as an example where the long term nature of these contracts places a special emphasis on the uncertain lifetime of the investor we incorporate the mortality risk and investigate its effect on the attractiveness of contracts offering minimum interest rate guarantees to eut and cpt investors for this purpose we introduce two approaches for the consideration of multiple risk sources within cpt we illustrate the theoretical framework with numerous simulations and our numerical results show that a long term risk averse eut investor prefers products with guarantees

current account solvency and the feldstein horioka puzzle in this paper we suggest an alternative explanation of the high cross section association between shares of saving and investment in gdp which feldstein and horioka 1980 interpret as evidence of low capital mobility in oecd countries saving and investment shares appear to be i i we show that a solvency constraint implies that the current balance is stationary and thus that saving and investment cointegrate with a unit coefficient irrespective of the degree of capital mobility it is this long run relation that the fh cross section regression captures econometric results for 23 oecd countries over the 1960 92 period are consistent with this explanation

the effects of annuities bequests and aging in an overlapping generations model of endogenous growth we examine the effects of introducing actuarially fair annuity markets into an overlapping generations model of endogenous growth the complete annuitisation of agents wealth is not in general dynamically optimal the degree of annuitisation that is dynamically optimal depends nonmonotonically on the expected length of retirement and on the pay as you go social security tax rate the government has an incentive to restrict the availability of actuarially fair annuities contracts and can often move the economy from a pay as you go to a fully funded social security system via voluntary contributions to a government sponsored actuarially fair pension today accompanied by reductions in social security taxes tomorrow

theory of constant proportion portfolio insurance abstract we study constant proportion portfolio insurance cppi a dynamic strategy that maintains the portfolio s risk exposure a constant multiple of the excess of wealth over a floor up to a borrowing limit we use this simple rule to investigate how transaction costs and borrowing constraints affect portfolio insurance type strategies absent transaction costs cppi is equivalent to investing in perpetual american call options and is optimal for a piecewise hara utility function with a minimum consumption constraint as the multiple increases the payoffs under cppi approach those of a stop loss strategy the expected holding period return is not monotonic in the multiple and a higher expected return can be obtained under cppi than with a stop loss strategy

different approaches for dealing with social security he u s social security system is a government pension program financed by worker payroll taxes as workers pay in their payroll taxes they accumulate credits toward benefits in the language of pensions this is a defined benefit plan at any point in time one can project tax inflows and benefit outflows based on various economic and demographic assumptions and determine the long run actuarial soundness of the system or to put it another way determine whether the present set of tax and benefit schedules will be consistent in the long term every year such forecasts are made by the social security and medicare trustees now three cabinet officers the commissioner of social security and two outside members social security and medicare boards of trustees 1995 every four years a quadrennial advisory council is appointed to review these forecasts and to comment on relevant policy issues in the past many of these councils have had important impacts on social security policy for example the 1983 greenspan commission proposed a number of measures that saved the system from imminent financial difficulty and the 1975 council recommended changing procedures that had until then led to overindexation of social security for inflation another advisory council was formed in 1994 and i was asked to chair it it also included three members from business three from unions and six others from the private pension industry the self employment sector and independent

option pricing and replication with transactions costs transactions costs invalidate the black scholes arbitrage argument for option pricing since continuous revision implies infinite trading discrete revision using black scholes deltas generates errors which are correlated with the market and do not approach zero with more frequent revision when transactions costs are included this paper develops a modified option replicating strategy which depends on the size of transactions costs and the frequency of revision hedging errors are uncorrelated with the market and approach zero with more frequent revision the technique permits calculation of the transactions costs of option replication and provides bounds on option prices

portfolio insurance and prospect theory investors popularity and optimal design of capital protected financial products abstract portfolio insurance strategies are used on both the institutional and the retail side of the asset management industry while standard utility theory struggles to provide an explanation this study justifies the popularity of portfolio insurance strategies in a behavioral finance context we run monte carlo simulations as well as historical simulations for popular portfolio insurance strategies and benchmark strategies in order to evaluate the outcomes using cumulative prospect theory our simulation results indicate that most portfolio insurance strategies are the preferred investment strategy for a prospect theory investor moreover the analysis provides insights into how portfolio insurance products should be designed and structured to meet the preferences of prospect theory investors as accurately as possible

aging pension reform and capital flows a multi country simulation model we present a quantitative analysis of the effects of population aging and pension reform on international capital markets first demographic change alters the time path of aggregate savings within each country second this process may be amplified when a pension reform shifts old age provision towards more pre funding third while the patterns of population aging are similar in most countries timing and initial conditions differ substantially hence to the extent that capital is internationally mobile population aging will induce capital flows between countries all three effects influence the rate of return to capital and interact with the demand for capital in production and with labor supply in order to quantify these effects we develop a computational general equilibrium model we feed this multi country overlapping generations model with detailed long term demographic projections for seven world regions our simulations indicate that capital flows from fast aging regions to the rest of the world will initially be substantial but that trends are reversed when households decumulate savings we also conclude that closed economy models of pension reform miss quantitatively important effects of international capital mobility this version 25 august 2004

on the existence of a unique correlated equilibrium in cournot oligopoly abstract in this paper i provide sufficient conditions under which the unique pure strategy nash equilibrium of the cournot oligopoly model with or without product differentiation is also the unique correlated equilibrium my conditions are 1 the demand function is linear and 2 the cost function is weakly convex

precautionary saving and accidental bequests this paper presents a simple general equilibrium model of precautionary saving and accidental bequests this model is used to analyze the implications of individual lifetime uncertainty for aggregate consumption and capital accumulation a precautionary demand for saving arises because an individual consumer does not know in advance the date at which he will die and he wants to avoid low levels of consumption in the event that he lives longer than expected an implication of this precautionary saving is that when death does occur the consumer is generally holding some wealth which is then passed on to his heirs in the form of an accidental bequest even if all consumers have the same ex ante mortality probabilities there will be some intracohort variation in the date of death consequently there will be a nondegenerate distribution of bequests left by consumers in a cohort this nondegenerate distribution of bequests left by one generation induces variation in the distributions of wealth consumption and bequests of subsequent generations the importance of bequests in aggregate saving has been established by laurence kotlikoff and lawrence summers 1981 who reported that 80 percent of u s household wealth is inherited wealth one interpretation of this finding is that the simple life cycle model without bequest motives is an inadequate description of saving behavior in the united states but the model i present demonstrates that accidental bequests by selfish consumers can account for a potentially sizeable fraction of aggregate wealth although some part of bequests especially by the wealthy undoubtedly results from an explicit bequest motive accidental bequests also play a role in the intergenerational transfer of wealth as well as in the intragenerational variation in wealth in order to focus on the role of accidental bequests i purposely exclude a bequest motive from the specification of the utility function the effects of lifetime uncertainty on individual consumption behavior were first examined formally in a seminal paper by menachem yaari 1965 yaari s model provided the basic framework for virtually all subsequent work on uncertain lifetimes including well known papers by nils hakansson 1969 stanley fischer 1973 robert barro and james friedman 1977 david levhari and leonard mirman 1977 and kotlikoff and avia spivak 1981 however all of these papers focused on the consumption decision of an individual and ignored the effect of accidental bequests on the behavior of the recipients of these accidental bequests 2 as will be shown at various points in this paper changes in the economic environment can have effects on aggregate behavior which differ sharply from the effects on individual behavior because of the endogenous adjustment of bequests the effects of department of economics harvard university cambridge ma 02138 this paper is a revised version of bequests and social security with uncertain lifetimes nber working paper no 1372 june 1984 i thank olivier blanchard john burbidge christopher cavanagh robert clower stanley fischer benjamin friedman elhanan helpman mervyn king nobuhiro kiyotaki laurence kotlikoff robert mcdonald james pesando julio rotemberg lawrence summers lars svensson mark watson and jeffrey wolcowitz for valuable conversations and correspondence i also thank the participants in seminars at boston university columbia university cornell university federal reserve board harvard university university of iowa mit university of minnesota university of montreal national bureau of economic research north carolina state university the wharton school and yale university and two anonymous referees for their helpful comments i also thank the national science foundation for financial support 1 in the presence of perfect annuity and life insurance markets there may or may not be bequests depending on the presence or absence of a bequest motive but there would be no accidental bequests 2 kotlikoff and spivak focus on the role of the family in providing an incomplete annuities market but stop short of a full scale overlapping generations model in which the distribution of bequests is determined endogenously

savings investment and international capital flows abstract the high correlation between national savings and domestic investment rateshas been interpreted as evidence that capital is not internationally mobile this paper surveys the theory and evidence on the relationship between savings and investment in a sample of 23 oecd countries a positive correlation between savings and investment rates is found in both the short and long runs however a wide variety of models generate such co movements in savings and investment in response to exogenous disturbances even under conditions of complete financial markets thus the savings investment correlation provides little evidence on the question of international capital mobility

performance evaluation of portfolio insurance strategies using stochastic dominance criteria abstract this paper evaluates the performance of the stop loss synthetic put and constant proportion portfolio insurance techniques based on a block bootstrap simulation we consider not only traditional performance measures but also some recently developed measures that capture the non normality of the return distribution value at risk expected shortfall and the omega measure we compare them to the more comprehensive stochastic dominance criteria the impact of changing the rebalancing frequency and level of capital protection is examined we find that even though a buy and hold strategy generates higher average excess returns it does not stochastically dominate the portfolio insurance strategies nor vice versa our results indicate that a 100 floor value should be preferred to lower floor values and that daily rebalanced synthetic put and cppi strategies dominate their counterparts with less frequent rebalancing

why is capital so immobile internationally possible explanations and implications for capital income taxation the evidence on international capital immobility is extensive including the lack of international portfolio diversification real interest differentials across countries and the high correlation between domestic savings and investment the authors develop a model with asymmetric information between countries that helps rationalize all the above observations and then examine the implications of this model for optimal domestic tax policy without asymmetric information past work showed that small open economies should not impose corporate income taxes with asymmetric information the optimal policy instead involves government subsidies to capital imports some omitted factors that argue against subsidizing capital imports are explored briefly copyright 1996 by american economic association

correlated equilibrium of cournot oligopoly competition abstract this paper shows that there is a unique correlated equilibrium which is the unique nash equilibrium for the standard cournot oligopoly model with linear demand and asymmetric linear costs journal of economic literature classification numbers c72 d43

the effects of volatility misestimation on option replication portfolio insurance to insure a stock portfolio one could purchase a put option with a striking price equal to some desired minimum value for the portfolio alternatively one could replicate this stock plus put portfolio with a portfolio of stock and cash the initial allocations to stock and cash will depend upon the parameters of an option valuation formula and will change as those parameters change in particular the construction of such synthetic optionreplicating portfolio insurance hence its outcome will depend critically on correct estimation of the volatility of the portfolio being insured volatility misestimation will cause the price of the synthetic put to deviate from its expected price and will result in incorrect allocations between stock and cash as a result the outcome of a synthetic portfolio insurance strategy based on misestimated volatility will be unpredictable a manager who underestimates volatility will typically end up buying less insurance than is necessary to ensure a given return while a manager who overestimates volatility will buy more insurance than is necessary both outcomes can be costly in terms of missed floors and forgone gains simulations of portfolio insurance performance over the period of the october 1987 market crash indicate that most insured portfolios would have fallen short of their promised values in general however the lower the guaranteed floor of the insurance program hence the lower its insurance the worse its results

does international coordination of pension policies boost capital accumulation within an olg framework we study a perfectly balanced pay as you go payg pension scheme in spite of its depressive impact on national saving payg is implemented for operating intergenerational transfers with international capital mobility the national adoption of payg determines a spill over effect through the world capital stock this creates a situation of interdependence among national pension policies that we model as a n countries dynamic game in contrast with previous literature it is shown that in general the international coordination of pension policies does not boost world savings and capital accumulation

explaining the energy efficiency gap expected utility theory versus cumulative prospect theory abstract energy efficiency is one of the key factors in mitigating the impact of climate change and preserving non renewable resources although environmental and economic justifications for energy efficiency investments are compelling there is a gap between the observable and some notion of optimized energy consumption the so called energy efficiency gap behavioral biases in individual decision making have been resonated by environmental research to explain this gap to analyze the influence of behavioral biases on decisions upon energy efficiency investments quantitatively we compare expected utility theory with cumulative prospect theory on basis of a real world example we illustrate how the extent of the gap is influenced by behavioral biases such as loss aversion probability weighting and framing our findings indicate that cumulative prospect theory offers possible explanations for many barriers discussed in literature for example the size of the gap rises with increased risk and investment costs because behavioral biases are systematic and pervasive our insights constitute a valuable quantitative basis for environmental policy measures such as customer focused and quantitatively backed public awareness campaigns financial incentives or energy savings insurances in this vein this paper may contribute to an accelerated adaption of energy efficiency measures by the broader public