efficient and durable decision rules with incomplete information we compare six concepts of efficiency for economies with incomplete information depending on the stage at which individuals welfare is evaluated and on whether incentive constraints are recognized an example is shown in which an incentive efficient decision rule may be unanimously rejected by the individuals in the economy we define durable decision rules which can resist such unanimous rejection and show that efficient durable decision rules exist

on the indifference relation in bewley preferences abstract bewley s 2002 influential model of preferences over uncertain prospects features an incomplete preference relation and a set of priors over the states of the world such that one act is preferred to another if and only if its expected utility is higher under every prior in that set this note shows that under general conditions on preferences the decision maker in the bewley model cannot be indifferent between distinct monetary acts whenever the set of priors is fully dimensional in the special case of two states in particular such objectively rational preferences are incomplete if and only if the indifference relation is trivial in the above sense

uncertainty and risk in financial markets this paper considers a general equilibrium model in which the distinction between uncertainty and risk is formalized by assuming agents have incomplete preferences over statecontingent consumption bundles as in bewley 1986 without completeness individual decision making depends on a set of probability distributions over the state space a bundle is preferred to another if and only if it has larger expected utility for all probabilities in this set when preferences are complete this set is a singleton and the model reduces to standard expected utility in this setting we characterize pareto optima and equilibria and show that the presence of uncertainty generates robust indeterminacies in equilibrium prices and allocations for any specification of initial endowments we derive comparative statics results linking the degree of uncertainty with changes in equilibria despite the presence of robust indeterminacies we show that equilibrium prices and allocations vary continuously with underlying fundamentals equilibria in a standard risk economy are thus robust to adding small degrees of uncertainty finally we give conditions under which some assets are not traded due to uncertainty aversion

lag length selection and tests of granger causality between money and income one of the most widely accepred relationships in macroeconomics is the positive relationship between the rate of growth of the money supply and the rate of growth of income a diversity of opinion arises however with the attempt to identify a causal relationship between these variables while friedman and schwartz 1963 initiated the empirical investigation of money income causality sims 1972 made the most significant contribution to this literature with a practical application of the criterion developed by granger 1969 for identifying a causal relationship since the appearance of sims s approach and an alternative one advanced by sargent 1976 many researchers have applied these techniques to the investigation of the causal relationship between money and income l with two exceptions hsiao 1981 and mcmillin and fackler 1984 these researchers have arbitrarily chosen the lengths of their distributed lags the purpose of this paper is to test for granger causality between money and income this paper differs from previous work in that considerably more attention is focused on the effect of the lag specification on the test results in particular we investigate the extent to which rules of thumb arbitrary lag specifications and

decentralization political competition and corruption abstract we study the effect of decentralization on corruption in a political agency model from the perspective of a region in a model where corruption opportunities are lower under centralization at each period of time decentralization makes it easier for citizens to detect corrupt incumbents as a consequence the relationship between fiscal decentralization and corruption is conditional on political competition decentralization is associated with lower higher levels of corruption for sufficiently high low levels of political competition we test this prediction and find that it is empirically supported also we show how the preferences of voters and politicians about fiscal decentralization can diverge in situations where political competition is weak

knightian uncertainty and moral hazard abstract this paper presents a principal agent model in which the agent has imprecise beliefs we model this situation formally by assuming the agent s preferences are incomplete as in bewley 1986 2 in this setting incentives must be robust to knightian uncertainty we study the implications of robustness for the form of the resulting optimal contracts we give conditions under which there is a unique optimal contract and show that it must have a simple flat payment plus bonus structure that is output levels are divided into two sets and the optimal contract pays the same wage for all output levels in each set we derive this result for the case in which the agent s utility function is linear and then show it also holds if this utility function has some limited curvature

financial complexity and trade what are the implications on trading activity if investors are not sophisticated enough to understand and evaluate trades that have a complex payoff structure can frictions generated by this type of financial complexity be so severe that they lead to a complete market freeze like that of the recent financial crisis starting from an allocation that is not pareto optimal we find that whether complexity impedes trade depends on how investors perceive risk and uncertainty for smooth convex preferences such as subjective expected utility complexity cannot halt trade even in the extreme case where each investor is so unsophisticated that he can only trade up to one arrow debreu security without being able to combine two or more in order to construct a complex trade however for non smooth preferences which allow for kinked indifference curves such as maxmin expected utility complexity can completely shut down trade

innovation and performance evidence at micro level this empirical study aims to shed light on the link between innovation and economic performance at micro level based on a comprehensive survey among dairy and crop farms in the netherlands we estimate a structural multi stage model to deliver evidence on the effect of engagement and investment in innovation on the production of product process and organizational or marketing innovations as well as on the effect of such innovations on farm level productivity the results suggest various market and farm behaviour related factors to stimulate an increase in innovation engagement and production furthermore the study reveals that indeed a greater innovation investment per unit innovation input leads to a higher probability of producing at least one successful product process and or organizational or marketing innovation innovation output the production of process and organizational or marketing related innovation leads to significant productivity gains various recommendations towards a more effective and efficient innovation policy are finally given

pareto optima and equilibria when preferences are incompletely known an exchange economy in which agents have convex incomplete preferences defined by families of concave utility functions is considered sufficient conditions for the set of efficient allocations and equilibria to coincide with the set of efficient allocations and equilibria that result when each agent has a utility in her family are provided welfare theorems in an incomplete preferences framework therefore hold under these conditions and efficient allocations and equilibria are characterized by first order conditions

trade with heterogeneous prior beliefs and asymmetric information no trade theorems have shown that new information will not lead to trade when agents share the same prior beliefs this paper explores the structure of no trade theorems with heterogeneous prior beliefs it is shown how different notions of efficiency under asymmetric information ex ante interim ex post are related to agents prior beliefs as well as incentive compatible and public versions of those efficiency concepts these efficiency results are used to characterize necessary and sufficient conditions on agents beliefs for no trade theorems in different trading environments

interim efficient allocations under uncertainty abstract this paper considers an exchange economy under uncertainty with asymmetric information uncertainty is represented by multiple priors and posteriors of agents who have either bewley s incomplete preferences or gilboa schmeidler s maximin expected utility preferences the main results characterize interim efficient allocations under uncertainty that is they provide conditions on the sets of posteriors thus implicitly on the way how agents update the sets of priors for non existence of a trade which makes all agents better off at any realization of private information for agents with the incomplete preferences the condition is necessary and sufficient but for agents with the maximin expected utility preferences the condition is sufficient only a couple of necessary conditions for the latter case are provided

have large budget deficits caused rising trade deficits for the united states the 1980s have been years of both large and unprecedented trade deficits as well as massive federal budget deficits the trade deficit rose from 25 billion in 1980 to 124 billion in 1985 during this same period federal budget deficits soared from 74 billion in 1980 to more than 212 billion in 1985 it is widely believed that the u s trade deficit rose mainly because of the skyrocketing federal budget deficit presenting such a view are for example hutchison and pigott 25 hutchison and pyle 26 clark 11 modigliani 30 and aschauer 2 besides economists many labor unions i e afl cio and official government documents see the economic report of the president particularly of 1984 have all shared similar views the issues involved have important policy implications suppose that the basic reason for rising trade deficits is indeed the escalating federal budget deficit in this case policy makers may focus on curtailing the budget deficit in order to resolve the trade deficit problem that has adversely affected several sectors such as manufacturing industries and agriculture however if such a view concerning the causal role of the budget deficit is incorrect then reductions in the federal budget deficit may not resolve the trade deficit dilemma and moreover attention will be diverted from more relevant and urgently needed policy options 6 the purpose of this paper is to empirically investigate the conventional argument that high federal budget deficit has been the prime cause of the escalating u s trade deficit finding only partial empirical evidence to support it in section ii i argue that most of previous studies in this area appear flawed by a methodological error rendering their tests unreliable for discriminating between a number of equally plausible hypotheses section iii describes the data and methodology used in the paper section iv presents the empirical results section v summarizes and concludes the paper

sharing risk and ambiguity we study the market implications of ambiguity in common models we show that generic determinacy is a robust feature in general equilibrium models that allow a distinction between ambiguity and risk

overlapping risk adjusted sets of priors and the existence of efficient allocations and equilibria with short selling the theory of existence of equilibrium with short selling is reconsidered under risk and ambiguity modelled by risk averse variational preferences no arbitrage conditions are given in terms of risk adjusted priors a sufficient condition for existence of efficient allocations is the overlapping of the interiors of the risk adjusted sets of priors or the inexistence of mutually compatible trades with non negative expectation with respect to any risk adjusted prior these conditions are necessary when agents are not risk neutral at extreme levels of wealths it is shown that the more uncertainty averse or risk averse the agents the more likely are efficient allocations and equilibria to exist

causality between dairy farm size and productivity the direction of causality between dairy farm size and productivity is examined for each state using multivariate granger causality tests the results only partially support the view that technological change has caused increases in dairy farm size the direction of causality appears to be more from size to productivity changes in productivity and average herd size appear driven by price changes

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

asset demands without the independence axiom an important application of the theory of choice under uncertainty is to asset markets and an important property in these markets is a preference for portfolio diversification if an investor is an expected utility maximizer then s he is risk averse if and only if s he exhibits a preference for diversification this paper examines the relationship between risk aversion and portfolio diversification when preferences over probability distributions of wealth do not have an expected utility representation

on the duality between prior beliefs and trading demands in an abstract model with asymmetric information we show that there is a duality relationship between the prior beliefs and trading demands of bets for any given individual then we aggregate all the agents to obtain a second duality relationship between common prior beliefs and trading possibilities we easily derive from these relationships the no trade theorem and its converse general efficiency results can be obtained moreover our framework is sufficiently general to cover special cases proved previously for example econometrica 62 1994 1327 discussion paper 83 center for rationality and interactive decision theory the hebrew university of jerusalem 1995 j econom theory 91 2000 127 gameseconom behav 24 1998 172 yet our argumentsare both simple and intuitive r 2003 published by elsevier science usa

interim efficiency with meu preferences abstract recently kajii and ui 2009 17 proposed to characterize interim efficient allocations in an exchange economy under asymmetric information when uncertainty is represented by multiple posteriors when agents have bewley s incomplete preferences kajii and ui 2009 17 proposed a necessary and sufficient condition on the set of posteriors however when agents have gilboa schmeidler s maxmin expected utility preferences they only propose a sufficient condition the objective of this paper is to complete kajii and ui s work by proposing a necessary and sufficient condition for interim efficiency for various models of ambiguity aversion and in particular maxmin expected utility our proof is based on a direct application of some results proposed by rigotti shannon and stralecki 2008 24

government capacities and policy making by decree in latin america the cases of brazil and argentina what is the effect of constitutional decree authority cda on the policy making process of a presidential regime despite recent efforts to answer this question there is still much uncertainty in the literature about the extent to which decree powers may allow presidents to control the legislative process this article argues that in a separation of powers system the existence of cda effectively enhances executives ability to act as agenda setters this capacity however is not uniform across all cases developing a simple spatial model of decree games the author argues that the bargaining power of an executive to promote legal changes through decrees varies according to three interrelated factors decree approval rules the extent of the executive s partisan support in the legislature and the strength of the presidential veto these propositions are supported by a comparative analysis of the process of constitutional design and the implementation of decrees in brazil and argentina two cases prese

the possibility of speculative trade between dynamically consistent agents it is shown that interim dynamically consistent trade may be supported among agents who have resolute non consequential choice preferences

a more robust definition of subjective probability the goal of choice theoretic derivations of subjective probability is to separate a decisionmaker s underlying beliefs subjective probabilities of events from their preferences attitudes toward risk classical derivations have all relied upon some form of the marschak samuelson independence axiom or the savage sure thing principle which imply that preferences over lotteries conform to the expected utility hypothesis this paper presents a choice theoretic derivation of subjective probability in a savage type setting of purely subjective uncertainty which neither assumes nor implies that the decisionmaker s preferences over lotteries necessarily conform to the expected utility hypothesis copyright 1992 by the econometric society

uncertainty efficiency and incentive compatibility ambiguity solves the conflict between efficiency and incentive compatibility abstract a fundamental result of modern economics is the conflict between efficiency and incentive compatibility that is the fact that some pareto optimal efficient allocations are not incentive compatible this conflict has generated a huge literature which almost always assumes that individuals are expected utility maximizers what happens if they have other kind of preferences is there any preference where this conflict does not exist can we characterize those preferences we show that in an economy where individuals have complete transitive continuous and monotonic preferences every efficient allocation is incentive compatible if and only if individuals have maximin preferences

structural and productivity change in us agriculture 1950 1982 this paper tests whether structural change in us agriculture is an important channel to tfp growth and evaluates the relative impact of i public research and education policies ii private r d and market forces and iii government farm programs on structural change we specify a structural econometric model fit it to us state aggregate data 1953 1982 and use the associated reduced form model to perform counter factual policy simulations the findings include structural change is a channel to tfp growth in both crop and livestock subsector i e specialization size and part time farming do impact tfp holding other variables constant public r d and education have been at least as important as private r d and market forces for changing livestock specialization farm size and farmers off farm work participation over the study period but private r d and market forces have been relatively more important for crop specialization changes in farm commodity programs had little impact on farm structure over these study period overall we conclude that if public r d and education policies had been unchanged at their 1950 values over 1950 1982 major structural changes in us agriculture would have occurred anyway the forces of private r d and market forces were at work including a decline in the price of machinery services and agricultural chemicals relative to the farm wage

risk sharing in the small and in the large abstract this paper analyzes risk sharing in economies with no aggregate uncertainty when agents have non convex preferences in particular agents need not be globally risk averse or uncertainty averse in the sense of schmeidler 1989 we identify a behavioral condition under which betting is inefficient i e every pareto efficient allocation provides full insurance and conversely if and only if agents supporting probabilities defined as in rigotti et al 2008 have a non empty intersection our condition is consistent with empirical and experimental evidence documenting violations of convexity in either outcomes or utilities our results show that the connection between speculative betting and inconsistent beliefs does not depend upon global notions of risk or ambiguity aversion

decision theory under ambiguity we review recent advances in the field of decision making under uncertainty or ambiguity we start with a presentation of the general approach to a decision problem under uncertainty as well as the standard bayesian treatment and issues with this treatment we present more general approaches choquet expected utility maximin expected utility smooth ambiguity and so forth that have been developed in the literature under the name of models of ambiguity sensitive preferences we draw a distinction between fully subjective models and models incorporating explicitly some information we review definitions and characterizations of ambiguity aversion in these models we mention the challenges posed by some of the models presented we end with a review of part of the experimental literature and applications of these models to economic settings

subjective beliefs and ex ante trade we study a definition of subjective beliefs applicable to preferences that allow for the perception of ambiguity and provide a characterization of such beliefs in terms of market behavior using this definition we derive necessary and sufficient conditions for the efficiency of ex ante trade and show that these conditions follow from the fundamental welfare theorems when aggregate uncertainty is absent our results show that full insurance is efficient if and only if agents share some common subjective beliefs our results hold for a general class of convex preferences which contains many functional forms used in applications involving ambiguity and ambiguity aversion we show how our results can be articulated in the language of these functional forms confirming results existing in the literature generating new results and providing a useful tool for applications

correlated nash equilibrium abstract we modify the epistemic conditions for nash equilibrium only to accommodate gilboa and schmeidler s i gilboa d schmeidler maxmin expected utility with nonunique prior j math econ 18 1989 141 153 maxmin expected utility preferences and identify the equilibrium concept in n player strategic games that characterizes the modified epistemic conditions the epistemic characterization supports the equilibrium concept as a minimal generalization of nash equilibrium in the sense that it deviates from nash equilibrium only in terms of players attitude towards ambiguity consequently comparing it with nash equilibrium constitutes a ceteris paribus study of the effects of ambiguity on how a game is played for example with ambiguity beliefs about action choices are in general correlated

ambiguity aversion in the long run to disagree we must also agree abstract we consider an economy populated by smooth ambiguity averse agents with complete markets of securities contingent to economic scenarios where bankruptcy is permitted but there is a penalty for it we show that if agents posterior belief reductions given by their average probabilistic beliefs do not become homogeneous then an equilibrium does not exist it is worth noting that our main result does not imply any convergence of ambiguity perception or even the attitudes towards it in this way complete markets with default and punishment allow for ambiguity aversion in the long run and the agents can disagree on their ambiguity perception but they must agree on their expected beliefs

a definition of uncertainty aversion a definition of uncertainty or ambiguity aversion is proposed it is argued that the definition is well suited to modelling within the savage as opposed to anscombe and aumann domain of acts the defined property of uncertainty aversion has intuitive empirical content behaves well in specific models of preference multiple priors and choquet expected utility and is tractable tractability is established through use of a novel notion of differentiability for utility functions called eventwise differentiability

brand dilution and the breakdown of political parties in latin america why would a national political party that has been competitive for decades collapse overnight in recent years parties across latin america went from being major contenders for executive office to electoral irrelevance over the course of a single electoral cycle the author develops an explanation that highlights the impact of elite actions on voter behavior during the 1980s and 1990s leaders across the region implemented policies that were inconsistent with their traditional party brand provoked internal party conflicts and formed strange bedfellow alliances with traditional rivals these actions diluted the brands of their parties eroding voters partisan attachments without the assured support of partisans parties become more susceptible to retrospective voting voters who now had no party attachments deserted incumbent parties when they performed poorly the author tests this interactive hypothesis using matched comparisons of six party election cases from argentina and venezuela

efficient allocations under ambiguity abstract important implications of the expected utility hypothesis and risk aversion are that if agents have the same probability belief then consumption plans in every efficient allocation of resources under uncertainty are comonotone with the aggregate endowment and if their beliefs are concordant then the consumption plans are measurable with respect to the aggregate endowment we study these two properties of efficient allocations for models of preferences that exhibit ambiguity aversion using the concept of conditional beliefs which we introduce in this paper we provide characterizations of such conditional beliefs for the standard models of preferences used in applications

out of the cabinet what drives defections from the government in presidential systems this article challenges a key part of the conventional view of coalitions in presidential systems that sees them as short lived and ad hoc the author shows instead that there is wide variation in the durability of governing coalitions across these regimes she develops a theory of the incentives of parties to participate in the government and the circumstances under which scholars might expect to see the existing governing coalition break down the author draws on data from 121 cabinets in 12 latin american countries between the late 1980s and the mid 2000s to show that the dissolution of the cabinet is more likely when the president places less value on coalition building as a policy making strategy and when parties find it costly to participate in the government in particular the author shows that strong unilateral institutional powers tend to diminish the incentives of presidents to compromise with other parties in contrast effective legislatures and high rates of approval for the executive contri