uncertainty and optimal taxation in defense of commodity taxes abstract this paper re examines the theory of optimal commodity taxation in the presence of a linear income tax under wage uncertainty there are two categories of goods the consumption levels in one group are committed to before the resolution of uncertainty and those of the other after the paper i characterizes the structure of the optimal commodity taxes in view of the insurance they provide against random wage movements ii proves that optimal taxation requires a mix of differential commodity taxes and a uniform lump sum tax and iii demonstrates that the post uncertainty goods should face a positive tax rate which is higher than the tax rate on the pre committed goods

applications of behavioural economics to tax evasion the paper reviews recent models that have applied the techniques of behavioural economics to the analysis of the tax compliance choice of an individual taxpayer the construction of these models is motivated by the failure of the yitzhaki version of the allingham sandmo model to predict correctly the proportion of taxpayers who will evade and the effect of an increase in the tax rate upon the chosen level of evasion recent approaches have applied non expected utility theory to the compliance decision and have addressed social interaction the models we describe are able to match the observed extent of evasion and correctly predict the tax effect but do not have the parsimony or precision of the yitzhaki model

optimism pessimism and financial bubbles this paper shows that it is possible to extend the scope of the existence of rational bubbles when uncertainty is introduced associated with rank dependent expected utility this rdu assumption can be viewed as a transformation of probabilities depending on the pessimism optimism of the agent the results show that pessimism favors the existence of deterministic bubbles when optimism may promote the existence of stochastic bubbles moreover under pessimism the rdu assumption may generate multiple bubbly equilibria the rdu assumption also leads to new conditions ensuring the absence of pareto optimality of the competitive equilibrium without bubbles these conditions still govern the existence of bubbles

cautious risk takers investor preferences and demand for active management actively managed mutual funds have distinct return distributions from their passive benchmarks and our theoretical analysis using tail sensitive risk preferences suggests that active value and growth funds may serve to reduce downside risk and capture upside potential respectively furthermore tail sensitivity measures estimated from the empirical pricing kernel have significant explanatory power for active fund flows even after controlling for business cycles and market wide sentiment finally active funds unlike their passive counterparts have exposures to option strategies hedging downside risk or capturing upside potential

risk rationality and time diversification the validity of the concept of time diversification is the subject of long running debate supporters of the concept argue that risk decreases as investment horizon increases detractors suggest that the concept is false on the face of it we argue that time diversification is consistent both theoretically and empirically with current conceptions of risk and rationality and we also note the implications of changes in investment horizon for stock market behavior

are preferences monotonic testing some predictions of regret theory in this paper the authors demonstrate that the assumption of regret aversion which has been invoked in regret theory to explain several well documented violations of expected utility theory also implies the existence of strict preferences between some stochastically equivalent actions and implies certain systematic violations of monotonicity the authors report an experimental test of these predictions they find that while choices between stochastically equivalent actions are entirely consistent with expected utility theory there is clear evidence of the monotonicity violations predicted by regret theory copyright 1992 by the london school of economics and political science

myopia redistribution and pensions this paper reviews a number of recent contributions that study pension design with myopic individuals its objective is to explore how the presence of more or less myopic individuals affects pension design when individuals differ also in productivity this double heterogeneity gives rise to an interesting interplay between paternalistic and redistributive considerations which is at the heart of most of the results that are presented the main part of the paper is devoted to the issue of pension design when myopic individual do not save enough for their retirement because their myopic self with a high discount rate emerges when labor supply and savings decisions are made some extensions and variations are considered in the second part in particular we deal with situations where labor disutility or preferences for consumption are subject to habit formation and where sin goods have a detrimental effect on second period health myopic individuals tend to underestimate the effects of both habit formation and sinful consumption which complicates public policy

computing multi period information constrained optima this paper presents a detailed theoretical derivation and justification for methods used to compute solutions to a multi period including infinite period continuum agent unobservedeffort economy actual solutions are displayed illustrating cross sectional variability in consumption and labour effort in the population at a point in time and variability for a typical individual over time the optimal tradeoff between insurance and incentives is explored and the issue of excess variability is addressed by consideration of the analogue full information economy and various restricted contracting regimes

designing optimal disability insurance a case for asset testing we analyze an implementation of an optimal disability insurance system as a competitive equilibrium with taxes an optimum is implemented by an asset tested disability system in which a disability transfer is paid only if an agent has assets below a specified maximum the logic behind this result is that an agent who plans to falsely claim disability a finds doing so unattractive if he does not adjust his savings and b cannot collect disability insurance if he does adjust his savings in the desired direction upward for a calibrated economy we find that welfare gains from asset testing are significant

asset allocation with distorted beliefs and transaction costs abstract in this paper we study the problem of the optimal portfolio selection with transaction costs for a decision maker who is faced with knightian uncertainty the decision maker s portfolio consists of one risky and one risk free asset and we assume that the transaction costs are proportional to the traded volume of the risky asset the attitude to uncertainty is modeled by the choquet expected utility we derive optimal strategies and bounds of the no transaction region for both optimistic and pessimistic decision makers the no transaction region of a pessimistic investor is narrower and its bounds lie closer to the origin than that of an optimistic trader moreover under the choquet expected utility the structure of the no transaction region is not necessarily a closed interval as it is under the standard expected utility model

a recursive formulation for repeated agency with history dependence abstract we present general recursive methods to handle environments where privately observed variables are linked over time we show that incentive compatible contracts are implemented recursively with a threat keeping constraint in addition to the usual temporary incentive compatibility and promise keeping conditions journal of economic literature classification numbers d30 d31 d80 d82

a test of the habit formation hypothesis using household data numerous studies have confirmed the importance of habit formation as represented by a lagged dependent variable in demand analysis although all work to date has been based on aggregate time series data this study uses household level bls interview panel data to test the habit hypothesis an interrelated demand system for seventeen goods is estimated from cross section data and compared with a similar system based on time series data the results show that the habit component is significantly different between the two data sets and much smaller in the cross section data habit effects while not as large in cross section data as time series are still highly significant several explanations are offered concerning why the two sets of estimates differ copyright 1991 by mit press

efficient allocations in dynamic private information economies with persistent shocks a first order approach this article studies efficient allocations in a dynamic private information economy with a continuum of idiosyncratic shocks that are persistent i develop a first order approach for this environment and show that the problem has a simple recursive structure that relies on only a small number of state variables making the problem tractable i find sufficient conditions that guarantee that the first order approach is valid to illustrate the first order approach i numerically compute the efficient allocations in a mirrleesean economy with productivity shocks that follow a random walk and verify the validity of the first order approach i show that persistent shocks create a new trade off where the social planner decreases the informational rent of the agent today at the cost of providing higher insurance in the future copyright 2013 oxford university press

insurance and taxation over the life cycle we consider a dynamic mirrlees economy in a life cycle context and study the optimal insurance arrangement individual productivity evolves as a markov process and is private information we use a first order approach in discrete and continuous time and obtain novel theoretical and numerical results our main contribution is a formula describing the dynamics for the labour income tax rate when productivity is an ar 1 our formula resembles an ar 1 with a trend where i the auto regressive coefficient equals that of productivity ii the trend term equals the covariance productivity with consumption growth divided by the frisch elasticity of labour and iii the innovations in the tax rate are the negative of consumption growth the last property implies a form of short run regressivity our simulations illustrate these results and deliver some novel insights the average labour tax rises from 0 to 37 over 40 years whereas the average tax on savings falls from 12 to 0 at retirement we compare the second best solution to simple history independent tax systems calibrated to mimic these average tax rates we find that age dependent taxes capture a sizable fraction of the welfare gains in this way our theoretical results provide insights into simple tax systems copyright 2013 oxford university press

bargaining and boldness abstract we study a multiperson bargaining problem with general risk preferences through the use of shaked s game of cycling offers with exogenous breakdown if preferences are smooth then as the risk of breakdown vanishes the limiting outcome is one in which bargainers are equally marginally bold where a bargainer s marginal boldness measures his willingness to risk disagreement in return for a marginal improvement in his position under smoothness any ordinal nash solution is an equally marginally bold outcome however unlike the concept of the ordinal nash solution a unique equally marginally bold outcome exists in natural cases in particular if all bargainers have risk averse preferences of the rank dependent expected utility type for these preferences the equally marginally bold outcome maximizes a bargaining power adjusted asymmetric nash product where the degree of asymmetry is determined by the disparity in the marginal valuation of certainty among bargainers journal of economic literature classification numbers c72 c78 d81

the cyclical and secular behaviour of the labour input comparing efficiency units and hours worked summary a monthly labour input series designed to correct for the fact that all hours worked are not of the same quality is constructed and its properties compared with unadjusted hours worked this efficiency units series is constructed from bls data on hours worked and earnings by age and sex the cyclical fluctuations displayed by the efficiency units series are smaller on average than those displayed by hours worked although the difference is not large however the secular behaviour of the series is quite different hours worked per capita displays a significant positive trend while efficiency units per capita does not

habit formation in consumption and its implications for monetary policy models this paper explores a monetary policy model with habit formation for consumers in which consumers utility depends in part on current consumption relative to past consumption the empirical tests developed in the paper show that one can reject the hypothesis of no habit formation with tremendous condence largely because the habit formation model captures the gradual hump shaped response of real spending to various shocks the paper then embeds the habit consumption specication in a monetary policy model and nds that the responses of both spending and inflation to monetary policy actions are signicantly improved by this modication jel d12 e52 e43

existence and uniqueness of ordinal nash outcomes abstract in this paper we present necessary and sufficient conditions for existence and uniqueness of ordinal nash outcomes these outcomes are derived from the ordinal nash solution a reinterpretation and an extension of the nash bargaining solution that allows bargainers to have preference relations that are more general than expected utility our task is undertaken by the construction of a new notion called induced utilities journal of economic literature classification number c78

credit markets with imperfect information risk aversion versus pessimism abstract stiglitz and weiss 1981 credit rationing is embedded within rank dependent expected utility theory our results show that sufficient pessimism or sufficient risk aversion by borrowers may eliminate adverse selection moreover lender optimism may eliminate credit rationing even when adverse selection exists

nonseparable preferences and optimal social security systems abstract in this paper we consider economies in which agents are privately informed about their skills which evolve stochastically over time we require agents preferences to be weakly separable between the lifetime paths of consumption and labor however we allow for intertemporal nonseparabilities in preferences like habit formation in this environment we derive a generalized version of the inverse euler equation and use it to show that intertemporal wedges characterizing optimal allocations of consumption can be strictly negative we also show that preference nonseparabilities imply that optimal differentiable asset income taxes are necessarily retrospective in nature we show that under weak conditions it is possible to implement a socially optimal allocation using a social security system in which taxes on wealth are linear and taxes transfers are history dependent only at retirement the average asset income tax in this system is zero

the probability premium a graphical representation we illustrate that pratt s probability premium can be given a simple graphical representation allowing a direct comparison to the equivalent but more prevalent concept of risk premium under expected utility we also show that the probability premium s graphical representation under the dual theory mimics that of the risk premium under expected utility

many good choice axioms when can many good lotteries be treated as money lotteries abstract without the independence axiom a weaker substitution axiom adi is necessary for the preferences over money lotteries induced by the money metric utility function to be well behaved given adi the agent s preferences over many good lotteries can be reconstructed from knowledge of preferences over money lotteries and over sure multivariate outcomes moreover other substitution properties of underlying many good lottery preferences are inherited by the money lottery preferences we analyze the formal and intuitive nature of adi and conclude that analysis of choice under uncertainty without adi cannot be one dimensional

cumulative prospect theory option returns and the variance premium the variance premium and the pricing of out of the money otm equity index options are major challenges to standard asset pricing models we develop a tractable equilibrium model with cumulative prospect theory cpt preferences that can overcome both challenges the key insight is that the variance premium can be written as the expected return on a portfolio of otm call and put options and the probability weighting feature of cpt can explain the puzzlingly low returns observed for these options using gmm on a sample of u s index option returns between 1996 and 2010 we show that the cpt model ts well observed option prices and therefore the variance premium in a dynamic setting probability weighting and time varying equity return volatility combine to match the observed time series pattern of the variance premium

a theory of subjective compound lotteries abstract we develop a savage type model of choice under uncertainty in which agents identify uncertain prospects with subjective compound lotteries our theory permits issue preference that is agents may not be indifferent among gambles that yield the same probability distribution if they depend on different issues hence we establish subjective foundations for the anscombe aumann framework and other models with two different types of probabilities we define second order risk as risk that resolves in the first stage of the compound lottery and show that uncertainty aversion implies aversion to second order risk which implies issue preference and behavior consistent with the ellsberg paradox

on the taxation of durable goods this paper proposes a mirrleesian theory of commodity taxation in the presence of durable goods nondurable goods should be taxed uniformly provided that the preferences over nondurable consumption are weakly separable from labor effort a uniform taxation across all goods is optimal if the utility from durable consumption is linear and the preferences are additively separable between durable goods nondurable goods and labor effort if those conditions are not met wealth effects and substitution effects justify the use of differential commodity taxes to characterize the sign of the tax differential the paper exploits a substitution euler equation that links the marginal rate of substitution between durable and nondurable consumption across time finally an application of this theory suggests that housing investment should face higher tax rates than nondurable consumption

are wages habit forming evidence from micro data although utility functions play a central role in economics the axiom that utility depends only on the absolute levels of its arguments is rarely tested this paper uses panel data on 2000 british employees who remain with the same employer and who are not promoted from one wave to the next it is shown that one important measure of well being overall job satisfaction is strongly positively correlated with the change in the worker s pay between waves but is unrelated to the current level of pay empirical tests suggest that a reference dependent satisfaction function where individual well being depends on current pay relative to past pay is more consistent with these regression results than are productivity or agency explanations of increasing wage profiles some evidence is presented of greater job satisfaction effects of pay rises for lower paid less well educated and younger workers these results provide some micro evidence consistent with the theory widespread in social science of habituation individuals may become used to any given level of consumption or income as such they tie in with the finding that a country s well being as measured by the average happiness of its citizens is only weakly correlated with its per capita gnp

optimal savings distortions with recursive preferences abstract this paper derives an intertemporal optimality condition for economies with private information focusing on a class of recursive preferences by comparing it to the situation where agents can freely save in a risk free asset market we derive the optimal savings distortions necessary for constrained optimality our recursive preferences are homogeneous and satisfy a balanced growth condition while allowing us to separate the role of risk aversion and intertemporal elasticity of substitution we perform some quantitative exercises that disentangle the respective roles played by these two parameters in optimal distortions and the implied welfare gains

expected utility violations implications for agricultural and natural resource economics nomic toolkit they compare the dogged defense of eu by economists to that of a monty python character playing the role of a petstore owner disputing the state of an obviously dead parrot the shop owner goes through incredible machinations to avoid replacing the bird let us consider another analogy the behavior of a caged parrot can likely tell us very little about the behavior of parrots in the wild a biologist may want to incorporate the behavior of caged parrots into the study of wild birds but would undoubtedly need to be extremely careful about understanding the underlying differences in the opportunities and constraints faced by caged versus wild birds before inferring much about wild parrot behavior to some extent experimental violations of eu present us with the same problem as the hypothetical parrot biologist subjects in these risk experiments are in a setting and are completing tasks very different from the setting and tasks they face in their everyday economic and social context what is missing relates to the power of the rationality assumption discussed in friedman that relies not only on the person s skill but also on the feedback they receive from the market friedman s expert billiards players are selected by a market because of their skill in billiards and th se are the players who fit friedman s as if description 1 risk researchers should not ignore experimental data however before we eliminate eu we should more fully understand the underlying reasons for the experimental behavior that violates eu agricultural and natural resource economists are well suited to assess

stochastic dominance in regret theory the regret theory of choice under uncertainty is known to admit intransitivities in preference relations in this paper the stochastic dominance properties of the theory are examined it is shown that the usual definition of first stochastic dominance is not satisfied by regret theoretic preferences and that in general violations of first stochastic dominance are not merely permitted but required an exact characterization of the stochastic dominance rule corresponding to regret theoretic preferences is presented this concept is weaker than the usual definition but stronger than the notion of statewise dominance in which one prospect yields a preferred outcome with probability 1 theories of choice under uncertainty have proliferated in recent years after a long period in which the expected utility eu approach of von neumann and morgenstern 1944 was pre eminent the breakdown of the dominance in eu theory reflects the increasing body of evidence that the choices made by many people systematically violate the predictions of the theory the axiomatic foundations of the theory and in particular the independence axiom have also received severe questioning ever since the famous critique of allais 1953

a theory of anticipated utility abstract a new theory of cardinal utility with an associated set of axioms is presented it is a generalization of the von neumann morgenstern expected utility theory which permits the analysis of phenomena associated with the distortion of subjective probability

discounting behavior a reconsideration we re evaluate the theory experimental design and econometrics behind claims that individuals exhibit non constant discounting behavior theory points to the importance of controlling for the non linearity of the utility function of individuals since the discount rate is defined over time dated utility flows and not flows of money it also points to a menagerie of functional forms to characterize different types of non constant discounting behavior the implied experimental design calls for individuals to undertake several tasks to allow us to identify these models and to several treatments such as multiple horizons and the effect of allowing for a front end delay on earlier payments the implied econometrics calls for structural estimation of the theoretical models allowing for joint estimation of utility functions and discounting functions using data collected from a representative sample of 413 adult danes in 2009 we draw striking conclusions assuming an exponential discounting model we estimate discount rates to be 5 6 on average this is significantly lower than all previous estimates using controlled experiments we also find no evidence to support quasi hyperbolic discounting or fixed cost discounting and only modest evidence to support other specifications of non constant discounting furthermore the evidence for non constant discounting while statistically significant is not economically significant in terms of the size of the estimated discount rates we undertake extensive robustness checks on these findings including a detailed review of the previous comparable literature

dynamic optimal taxation with private information we study dynamic optimal taxation in a class of economies with private information optimal allocations in these environments are complicated and history dependent yet we show that they can be implemented as competitive equilibria in market economies supplemented with simple tax systems the market structure in these economies is similar to that in bewley 1986 agents supply labour and trade risk free claims to future consumption subject to a budget constraint and a debt limit optimal taxes are conditioned only on two observable characteristics an agent s accumulated stock of claims or wealth and her current labour income we show that optimal taxes are generally non linear and non separable in these variables and relate the structure of marginal wealth and income taxation to the properties of agent preferences this paper studies optimal taxation in a class of dynamic economies with private information we consider an environment in which agents preferences are defined over consumption and labour and each agent receives a privately observed sequence of i i d preference shocks incentivecompatibility constraints stemming from private information imply that socially optimal or constrained efficient allocations in this environment are complicated and history dependent yet we show that they can be implemented as competitive equilibria in market economies supplemented with simple tax systems the market structure in these economies is identical to that in bewley 1986 huggett 1993 or aiyagari 1994 agents can trade current consumption for claims to future consumption subject to a budget constraint and a borrowing limit these claims have a non contingent pre tax return crucially taxes are conditioned upon only two observable characteristics of an agent current wealth given by the agent s accumulated stock of claims and current labour income they do not depend on any other aspect of an agent s past history most models of dynamic optimal taxation follow the ramsey approach in which the set of fiscal instruments available to the government is exogenously specified 1 linear labour and capital income taxes are typically included in this set while lump sum taxes are ruled out the exclusion of the latter is justified by appealing to incentive or administrative constraints but these are not explicitly modelled these exogenous restrictions on fiscal instruments represent frictions that the government seeks to ameliorate through its optimal choice of tax rates the approach we adopt in this paper builds on the optimal taxation literature initiated by mirrlees 1971 mirrlees assumes that agents receive privately observed shocks to their

optimal indirect and capital taxation we consider an environment in which agents skills are private information and follow arbitrary stochastic processes we prove that it is typically pareto optimal for an individual s marginal benefit of investing in capital to exceed his marginal cost of doing so this wedge is consistent with a positive tax on capital income we also prove that it is pareto optimal for the marginal rate of substitution between any two consumption goods to equal the marginal rate of transformation this lack of a wedge is consistent with uniform taxation of consumption goods within a period

the nash bargaining solution for decision weight utility functions abstract a simple derivation of the non expected utility nash outcome as defined in rubinstein et al 1992 rubinstein a safra z thomson w 1992 on the interpretation of the nash bargaining solution and its extension to non expected utility preferences econometrica 60 1171 1186 is given for the class of decision weight utility functions conditions for existence and uniqueness are provided

consumption and labor supply with partial insurance an analytical framework we develop a model with partial insurance against idiosyncratic wage shocks to quantify risk sharing closed form solutions are obtained for equilibrium allocations and for moments of the joint distribution of consumption hours and wages we prove identification and demonstrate how labor supply data are informative about risk sharing the model estimated with us data over the period 1967 2006 implies that i 39 percent of permanent wage shocks pass through to consumption ii the share of wage risk insured increased until the early 1980s and iii preference heterogeneity is important in accounting for observed dispersion in consumption and hours jel e21 e23 e31 e52

household portfolio diversification a case for rank dependent preferences the proliferation of novel preference theories in financial economics is hampered by a lack of non experimental evidence and by the theories additional complexity which has not been shown to be critical in applications in this article i present arguments in support of preferences with rank dependency using the survey of consumer finances data i document two widespread patterns inconsistent with expected utility i many households simultaneously invest in well deversified funds and in poorly diversified portfolios of stocks and ii some households with substantial savings do not invest anything in equities i show that portfolio choice models with rank dependent preferences plausibly parameterized and under fully rational assumptions are quantitatively consistent with the observed diversification these results call for further efforts to integrate the models of rank dependent preferences in portfolio theory and asset pricing the decision theoretic literature has long acknowledged the shortcomings of the expected utility theory of von neumann and morgenstern 1944 several generalizations of the theory are inspired by the experimental evidence and aimed at improving its descriptive accuracy however there are few applications of new models of preferences in finance and expected utility continues to dominate the field 1 two principal hurdles slow the proliferation of novel preferences in financial economics first the lack of empirical non experimental or field data confirming that the behavior motivating non expected utilities is widespread outside the laboratory settings second the additional and often significant complexity of the alternative preferences which has not been shown to be critical in applications where the models based on expected utility fall short of reasonable predictions this article presents empirical and theoretical this paper was previously circulated under the title household portfolio diversification the paper has benefited from the comments of shlomo benartzi luca benzoni markus brunnermeier john dickhaut maria perozek raj singh hersh shefrin and workshop participants at minnesota finance bag lunch 2003 wharton conference household financial decision making and portfolio choice and 2003 summer meetings of econometric society i would like to thank cam harvey the editor and an anonymous referee for many helpful comments and suggestions a special thanks to jack kareken for comments and editorial help on an earlier draft i am grateful to donna zerwitz for editorial assistance the views expressed herein are those of the author and not necessarily of the federal reserve bank of minneapolis or the federal reserve system all errors and omissions are the sole responsibility of the author address correspondence to valery polkovnichenko finance 3 122 csom 319 19 th

the invention of the independence condition for preferences this paper discusses the history and interrelations of three central ideas in preference theory the independence condition in decision under risk the sure thing principle in decision under uncertainty and conjoint independence for multiattribute decisions and consumer theory independence was recognized as an important component of decision under risk in the late 1940s by jacob marschak john nash herman rubin and norman dalkey and first appeared in publication in marschak marschak j 1950 rational behavior uncertain prospects and measurable utility econometrica18 111 141 and nash nash j f 1950 the bargaining problem econometrica18 155 162 the sure thing principle can be credited to savage savage l j 1953 une axiomatisation du comportement raisonnable face i l incertitude colloq internal centre national rech sci 40 econometrie 29 40 savage l j 1954 the foundations of statistics wiley new york 2nd edn dover new york 1972 conjoint independence for consumer theory was introduced by sono sono m 1943 the effect of price changes on the demand and supply of separable goods in japanese kokumin keisai zasshi74 1 51 and leontief leontief w w 1947a a note on the interrelation of subsets of independent variables of a continuous function with continuous first derivatives bull amer math soc 53 343 350 leontief w w 1947b introduction to a theory of the internal structure of functional relationships econometrica51 361 373 a form of it can also be recognized in samuelson samuelson p a 1947 foundations of economic analysis harvard university press cambridge ma presented earlier in samuelson samuelson p a 1940 foundations of analytical economics the observational significance of economic theory ph d dissertation harvard university boston ma independence and the sure thing principle are equivalent for decision under risk but in a less elementary way than has sometimes been thought the sure thing principle for decision under uncertainty and conjoint independence are identical in a mathematical sense the mathematics underlying our three preference conditions has an older history the independence condition for decision under risk can be recognized in the characterization of associative means and conjoint independence for multiattribute decisions in solutions to the generalized associativity functional equation

choice under uncertainty evidence from ethiopia india and uganda we review experimental evidence collected from risky choice experiments using poor subjects in ethiopia india and uganda using these data we estimate that just over 50 of our sample behaves in accordance with expected utility theory and that the rest subjectively weight probability according to prospect theory our results show that inferences about risk aversion are robust to whichever model we adopt when we estimate each model separately however when we allow both models to explain portions of the data simultaneously we infer risk aversion for subjects behaving according to expected utility theory and risk seeking behaviour for subjects behaving according to prospect theory

optimal taxation and human capital policies over the life cycle this paper derives optimal income tax and human capital policies in a life cycle model with risky human capital the government faces asymmetric information regarding agents ability its evolution and labor supply when the wage elasticity with respect to ability is increasing in human capital the optimal subsidy involves less than full deductibility of human capital expenses on the tax base and falls with age income contingent loans or a deferred deductibility scheme can implement the optimum numerical results suggest that full deductibility of expenses is close to optimal and that simple linear age dependent policies perform very well

lottery expenditures in canada a regional analysis of determinants and incidence this article examines two issues first it evaluates the statistical significance of a number of socio economic and demographic variables on the level of household lottery expenditures in the six regions of canada while some household characteristics vary in the extent to which they significantly affect the level of lottery expenditures across regions wealth age occupation mother tongue and urban location for example others are significant in every region regional consistency exists in the statistical significance of after tax household income sex and education of the head of household lottery expenditures increase as incomes increase lottery expenditures are significantly lower for female heads of households than for their male counterparts lottery expenditures decline as the education level of the head of household increases second lottery expenditures are found to be regressive although the degree of regressivity is less than for lotteries in the united states

optimism and pessimism in games this paper considers the impact of ambiguity in strategic situations it extends the earlier literature by allowing for optimistic responses to ambiguity ambiguity is modelled by ceu preferences we propose a new solution concept for players who may express ambiguitypreference then we study comparative statics of changes in ambiguity attitude in games with strategic complements this gives a precise statement of the impact of ambiguity on economic behaviour

optimal taxation in a habit formation economy abstract this paper studies habit formation in consumption preferences in a dynamic mirrlees economy we derive optimal labor and savings wedges based on a recursive approach we show that habit formation creates a motive for subsidizing labor supply and savings in particular habit formation invalidates the well known no distortion at the top result we demonstrate that the theoretical findings are quantitatively important in a parametrized life cycle model average labor and savings wedges fall by more than one third compared with the case of time separable preferences

optimal human capital policies abstract we analyze optimal income taxes and optimal schooling subsidies in a dynamic private information economy with observable human capital accumulation we show that under plausible conditions the marginal schooling subsidies are positive and that they are zero at both endpoints of the skill distribution we compute the optimal policies and evaluate their impact over the transition and at the steady state we find that the optimal schooling policies are significantly smaller than the optimal marginal income taxes if optimal schooling policies are introduced jointly with optimal income taxes then their welfare and aggregate effects are small however if income taxes are not set optimally then the optimal schooling policies have significant welfare and aggregate effects

on repeated moral hazard with discounting in this paper we analyze optimal contracts in an infinitely repeated agency model in which both the principal and agent discount the future we show that there is a stationary representation of the optimal contract when the agent s conditional discounted expected utility is used as a state variable this representation reduces the multi period problem to a static variational problem which can be analyzed using standard variational techniques this reduction is used to obtain several properties of the contract

portfolio choice in personal equilibrium abstract this paper finds that in portfolio choice where reference point arises endogenously in personal equilibria investors behave as if they had a concave probability weighting function this finding establishes a link between the reference dependent utility and the rank dependent utility theories

risky human capital and deferred capital income taxation abstract we study the structure of optimal wedges and capital taxes in a dynamic mirrlees economy with endogenous distribution of skills human capital is a private stochastic state variable that drives the skill process of each individual building on the findings of the labor literature we construct a tractable life cycle model of human capital evolution with risky investment and stochastic depreciation in this setting we demonstrate the optimality of a a human capital premium i e an excess return on human capital relative to physical capital b a large intertemporal wedge early in the life cycle and c a non zero intratemporal wedge even at the top of the skill distribution at all dates except the last date in the life cycle the main implication for the structure of optimal linear capital taxes is the necessity of deferred taxation of physical capital the average marginal tax rate on physical capital held in every period is zero in present value however expected capital tax payments do not equal zero in every period necessarily agents face negative expected capital tax payments early in the life cycle and positive expected capital tax payments late in the life cycle

stochastic dominance analysis without the independence axiom we characterize the consistency of a large class of nonexpected utility preferences including mean variance preferences and prospect theory preferences with stochastic orders for example stochastic dominances of different degrees our characterization rests on a novel decision theoretic result that provides a behavioral interpretation of the set of all derivatives of the functional representing the decision maker s preferences as an illustration we consider in some detail prospect theory and choice acclimating preferences two popular models of reference dependence under risk and we show the incompatibility of loss aversion with prudence this paper was accepted by james smith decision analysis

optimum taxation with errors in administration abstract the paper compares the welfare levels which can be achieved by two distinct tax regimes lump sum taxation where one attempts to identify individuals and allocate transfers or subsidies on the basis of characteristics and income taxation where characteristics are not observed but personal incomes are measured and taxed where there are no errors in classifying individuals lump sum taxation is superior but where mistakes are made in the allocation of lump sum grants or subsidies income taxation may be more attractive the level of errors where the regimes are equally desirable in terms of social welfare is computed in simple models following that of feldstein 1973 where there is strong aversion to inequality then income taxation becomes preferable at quite small errors in analysing income taxation it is shown that in the feldstein model with endogenous wages the marginal tax rate in optimum income taxation on the more skilled is negative and that on the less skilled is positive in contrast to the standard results see seade 1977 with exogenous wages

habit formation and the theory of addiction in the light of repeated rejections of the hall 1978 version of the life cycle permanent income hypothesis and other empirical puzzles the habit formation hypothesis has increased in popularity since the 1980s however existing formulations of habit persistence do not always perform well empirically this paper pursues two objectives i to outline the habit persistence hypothesis and ii to review the theory of addiction with a focus on issues of relevance to the theory of consumption in the literature on addiction two research traditions are discernible rational addiction and myopic addiction the former approach emphasises forward looking behaviour and defines memory loss as a univariate process the latter relies on multiple objectives and highlights the role of contractual behaviour the paper argues that future research in consumption with habits ought to pay more attention to non separabilities allow for multivariate processes when modelling memory loss and consider rational habit modification

self selection and pareto efficient taxation abstract this paper analyses the set of pareto efficient tax structures the formulation of the problem as one of self selection not only shows more clearly the similarity between this problem and a number of other problems such as the optimal pricing of a monopolist which have recently been the subject of extensive research but also allows the derivation of a number of new results we establish i under fairly weak conditions randomization of tax structures is desirable ii if different individuals are not perfect substitutes for one another in production then the general equilibrium effects until now largely ignored in the literature of changes in the tax structure may be dominant in determining the optimal tax structure in particular if the relative wage of high ability and low ability individuals depends on the relative supplies of labor the optimal tax structure entails a negative marginal tax rate on the high ability individuals and a positive marginal tax rate on the low ability individuals the marnitude of which depends on the elasticity of substitution iii if individuals differ in their preferences pareto efficient taxation may entail negative marginal tax rates for high incomes while iv if wage income is stochastic the marginal tax rate at the upper end may be 100 our analysis thus makes clear that the main qualitative properties of the optimal tax structure to which earlier studies called attention are not robust to these attempts to make the theory more realistic