an efficiency theorem for incompletely known preferences there are n agents who have von neumann morgenstern utility functions on a finite set of alternatives a each agent i s utility function is known to lie in the nonempty convex relatively open set ui suppose l is a lottery on a that is undominated meaning that there is no other lottery that is guaranteed to pareto dominate l no matter what the true utility functions are then there exist utility functions ui ui for which l is pareto efficient this result includes the ordinal efficiency welfare theorem as a special case

efficient resource allocation on the basis of priorities many institutions allocate resources by non market mechanisms based on priorities in this paper we introduce a model of resource allocation on the basis of priorities and address the following questions is it possible to allocate resources on the basis of any priority structure if yes when can we do this pareto efficiently without creating incentives for manipulation and consistently across different groups of agents and resource levels we adopt a basic indivisible objects model with a finite number of object types and a finite quota of goods of each type some interesting examples are the determination of access to education allocation of graduate houses offices or tasks agents are assumed to have strict preferences over object types and remaining unassigned an assignment is an allocation of the objects to the agents such that every agent receives at most one object a rule associates an assignment to each preference profile we formalize a priority structure to be a collection of strict priority rankings of individuals indexed by the object types where i a j would be read as i has higher priority for object a than j we assume that the priority structure is exogenously fixed and allow the preferences of the agents to vary a rule is said to violate a priority of i for a if there is a preference profile under which i envies j who is assigned a and publication information econometrica 70 6 november 2002 2489 2497 the copyright to this article is held by the econometric society http www econometricsociety org it may be downloaded printed and reproduced only for personal or classroom use absolutely no downloading or copying may be done for or on behalf of any for profit commercial firm or other commercial purpose without the explicit permission of the econometric society for this purpose contact julie p gordon executive director of the society at jpg northwestern edu i would like to thank faruk gul wolfgang pesendorfer the co editor the four anonymous referees and the participants of the micro theory lunch seminar in princeton university for their comments and suggestions

on the existence of a strictly strong nash equilibrium under the student optimal deferred acceptance algorithm abstract this study analyzes a preference revelation game in the student optimal deferred acceptance algorithm in a college admission problem we assume that each college s true preferences are known publicly and analyze the strategic behavior of students we demonstrate the existence of a strictly strong nash equilibrium in the preference revelation game through a simple algorithm that finds it specifically i the equilibrium outcome from our algorithm is the same matching as in the efficiency adjusted deferred acceptance algorithm and ii in a one to one matching market it coincides with the student optimal von neumann morgenstern vnm stable matching we also show that i when a strict core allocation in a housing market derived from a college admission market exists it can be supported by a strictly strong nash equilibrium and ii there exists a strictly strong nash equilibrium under the college optimal deferred acceptance algorithm if and only if the student optimal stable matching is pareto efficient for students

on two competing mechanisms for priority based allocation problems we consider the priority based allocation problem there is a set of indivisible objects with multiple supplies e g schools with seats and a set of agents e g students with priorities over objects e g proximity of residence area we study two well known and competing mechanisms the agentoptimal stable mechanism aosm allots objects via the deferred acceptance algorithm the top trading cycles mechanism ttcm allots objects via gale s top trading cycles algorithm we show that the two mechanisms are equivalent or ttcm is fair i e respects agents priorities or resource monotonic o rpopulation monotonic if and only if the priority structure is acyclic furthermore if aosm fails to be efficient consistent for a problem ttcm also fails to be fair consistent for it however the converse is not necessarily true

stable and efficient resource allocation under weak priorities abstract we study the indivisible object allocation problem without monetary transfer in which each object is endowed with a weak priority ordering over agents it is well known that stability is generally not compatible with efficiency we characterize the priority structures for which a stable and efficient assignment always exists as well as the priority structures that admit a stable efficient and group strategy proof rule while house allocation problems and housing markets are two classic families of allocation problems that admit a stable efficient and group strategy proof rule any priority augmented allocation problem with more than three objects admits such a rule if and only if it is decomposable into a sequence of subproblems each of which has the structure of a house allocation problem or a housing market

boston versus deferred acceptance in an interim setting an experimental investigation abstract while much of the school choice literature advocates strategyproofness recent research has aimed to improve efficiency using mechanisms that rely on non truthtelling equilibria we address two issues that arise from this approach we first show that even in simple environments with ample feedback and repetition agents fail to reach non truthtelling equilibria we offer another way forward implementing truth telling as an ordinal bayes nash equilibrium rather than as a dominant strategy equilibrium we show that this weaker solution concept can allow for more efficient mechanisms in theory and provide experimental evidence that this is also the case in practice in fact truth telling rates are basically the same whether truthtelling is implemented as an ordinal bayes nash equilibrium or a dominant strategy equilibrium this provides a proof of concept that ordinal bayes nash design might provide a middle path achieving efficiency gains over strategy proof mechanisms without relying on real life agents playing a non truth telling equilibrium

strategy proof exchange we consider the allocation of goods in exchange economies with a finite number of agents who may have private information about their preferences in such a setting standard allocation rules such as walrasian equilibria or rational expectations equilibria are not compatible with individual incentives we characterize the set of allocation rules which are incentive compatible or in other words the set of strategy proof social choice functions social choice functions which are strategy proof are those which can be obtained from trading according to a finite number of pre specified proportions the number of proportions which can be accommodated is proportional to the number of agents such rules are necessarily inefficient even in the limit as the economy grows

on the sign of the optimum marginal income tax this paper studies a central aspect of optimal income taxation as modelled in mirrlees original paper on the topic identical leisure consumption preferences qualitatively homogeneous skills in production namely whether given concave utilitarianism alone the optimal marginal income tax will be non negative a well known positive answer to this question in weak inequality form was given in the said paper which however we show requires additive separability of individual utility in the ordinal and cardinal senses our main result here is to derive the required strict positivity of the marginal tax under weak conditions slightly wider than noninferiority of consumption and leisure with preferences otherwise arbitrary

constrained school choice an experimental study 31 pages 18 tables jel classification c72 c78 d78 i20 trabajo publicado como articulo en american economic review 100 4 1860 1874 2010 http dx doi org 10 1257 aer 100 4 1860

on the optimal income taxation and educational decisions abstract in this paper we consider three different ways of incorporating individuals educational choices into the design of optimal income tax policy in one variant of the model case 2 where an individual chooses his education before knowing his ability and after that education makes his labour supply decisions on the basis of known ability it is shown that qualitative features of the optimal income tax schedule are not similar to those of the standard optimal income tax model the marginal tax rate is generally not zero at the endpoints of distribution but is most likely negative using numerical methods some interesting features quite different from earlier numerical results are revealed especially in the second case for example the marginal tax rate is non decreasing in income for a substantial income range in addition our calculations support neither the traditional views on the egalitarian nature of equal education nor its disadvantageous consequences in the perfect utilitarian society

altruism jealousy and the theory of optimal non linear taxation abstract this paper studies optimal non linear taxes in a world in which there is altruism and jealousy a formula for optimal marginal tax rates is derived which turns out to be a simple and intuitively appealing extension of a result due to mirrlees the paper shows that in this sort of economy all of optimal tax theory s general results either no longer hold or need not hold and it sets out appropriate modifications to standard tax rules

efficient resource allocation under multi unit demand abstract we study resource allocation with multi unit demand such as the allocation of courses to students in contrast to the case of single unit demand no stable mechanism not even the student proposing deferred acceptance algorithm achieves desirable properties it is not strategy proof and the resulting allocation is not even weakly efficient under submitted preferences we characterize the priority structure of courses over students under which stability is consistent with strategy proofness or efficiency we show that stability is compatible with strategy proofness or efficiency if and only if the priority structure is essentially homogeneous this result suggests that efficient allocation under multi unit demand is difficult and that the use of stable mechanisms may not deliver desirable outcomes

should educational expenses be deductible a comparison of tax bases in a model where education is a choice variable abstract the paper studies the design of an educational policy within the context of an optimal taxation model where individuals are free to choose how much education to acquire and also have a discrete labor leisure choice a linear income tax and tax deductibility of educational expenses are the only instruments available to the government whose goal it is to use these instruments so as to maximize the utility of the worst off individual in society the main focus of the study is how large a fraction of educational expenses should be deductible a variation of this fraction has several opposing effects the optimal size of the fraction depends therefore in a complicated way on the distribution of ability the costs of producing education and the effect of education on wages and productivity there is no general case either for no deductibility or for full deductibility

local social capital and geographical mobility in the north of europe club membership is higher than in the south but the frequency of contacts with friends relatives and neighbors is lower we link this fact to another one the low geographical mobility rates in the south of europe relative to the north to interpret these facts we build a model of local social capital and mobility investing in local ties is rational when workers do not expect to move to another region we find that observationally close individuals may take different paths characterized by high local social capital low mobility and high unemployment vs low social capital high propensity to move and higher employment probability employment protection reinforces the accumulation of local social capital and thus reduces mobility european data supports the theory within a country and at the individual level more social capital is associated with lower mobility

matching markets with mixed ownership the case for a real life assignment mechanism we consider a common indivisible good allocation problem whose popular applications include on campus housing kidney exchange and school choice we show that the so called new house 4 nh4 mechanism which has been in use at mit since the 1980s is equivalent to a natural adaptation of the well known gale shapley gs mechanism we run two experiments comparing nh4 with the prominently advocated top trading cycles ttc mechanism and nh4 with gs we find that under nh4 the participation rate is significantly higher than under ttc based on a new ordinal test of efficiency nh4 is more likely to pareto dominate ttc

strategy proof assignment on the full preference domain we consider the problem of efficiently allocating several indivisible objects between agents who are to receive at most one object and whose preferences are private information we examine this standard assignment problem from the perspective of mechanism design giving up the usual assumption of linear preferences and instead using a full preference domain with indifferences permitted we characterize two classes of mechanisms i bi polar serially dictatorial rules by essential single valuedness pareto indifference strategy proofness and non bossiness and ii all selections from bi polar serially dictatorial rules by single valuedness efficiency strategy proofness and weak non bossiness we compare the outcomes from the bi polar serially dictatorial rules with the outcomes obtained using a market based approach namely the core of the market we show that all strongly efficient outcomes in the core can be generated using serially dictatorial rules moreover we argue that serially dictatorial rules have an advantage over the market based approach in that they yield strongly efficient solutions for all preference profiles making it possible to use randomization to restore equity when preferences are private information this type of ex ante equity cannot be implemented using the market based approach

on the role of the production and consumption assumptions for optimum taxation abstract the sensitivity of optimum tax rates to a variety of factors has sustained many different lines of enquiry this paper attempts to demonstrate by computational procedures the role of the production and consumption leisure assumptions in the light of recent research in particular the work of stern will be extended to provide an assessment of the allen analysis it will be shown that optimum negative marginal tax rates are no longer a curiousity and that our production and consumption leisure assumptions are of considerable importance for variable wage tax models

broadening the market design approach to school choice school choice refers to policies that allow parents preferences to be an input to the decision of which school a student will attend a rich body of research has developed over the past 10 15 years to study mechanisms that implement school choice this literature has mostly taken the inputs of school choice preferences priorities and capacities as exogenous more recently researchers have sought to embed the school choice problem into its wider context thereby broadening the scope of market design questions and enriching the analysis this article discusses current school choice policy issues in light of this recent literature and outlines remaining open questions

the equitable top trading cycles mechanism for school choice the equitable top trading cycles mechanism a particular adaptation of gale s top trading cycles ttc procedure applied to school choice the so called ttc mechanism has attracted much attention both in theory and practice due to its superior efficiency and incentive features we discuss and introduce alternative adaptations of gale s original procedure that can offer improvements over ttc in terms of equity along with various other distributional considerations instead of giving all the trading power to those students with the highest priority for a school we argue for the distribution of the trading rights of all slots of each school this allows them to trade in a thick market where additional constraints can be accommodated by choosing an appropriate pointing rule we propose a particular mechanism of this kind the equitable top trading cycle ettc mechanism which is also pareto efficient and group strategy proof just like ttc and eliminates avoidable justified envy situations ettc generates significantly fewer justified envy situations than ttc both in simulations and the lab

matching with couples stability and incentives in large markets accommodating couples has been a longstanding issue in the design of centralized labor market clearinghouses for doctors and psychologists because couples view pairs of jobs as complements a stable matching may not exist when couples are present this paper s main result is that a stable matching exists when there are relatively few couples and preference lists are suciently short relative to market size we also discuss incentives in markets with couples we relate these theoretical results to the job market for psychologists in which stable matchings exist for all years of the data despite the presence of couples

a dynamic school choice model this paper inspires from a real life assignment problem faced by the mexican ministry of public education we introduce a dynamic school choice problem that consists in assigning positions to overlapping generations of teachers from one period to another teachers can either retain their current positions or choose a preferred one in this framework a solution concept that conciliates the fairness criteria with the individual rationality condition is introduced it is then proved that a solution always exists and that it can be reached by a modified version of the deferred acceptance algorithm of gale and shapley we also show that the mechanism is dynamically strategy proof and respects improvements whenever the set of orders is lexicographic by tenure

matching with contracts comment the theory of two sided matching markets has interested researchers for its theoretical appeal and its relevance to the design of real world institutions the medical residency matching mecha nism in the united states the national resident matching program nrmp and student assign ment systems in new york city and boston are important mechanisms designed by economists using the theory 1 hatfield and paul r milgrom 2005 present a unified framework of matching with contracts which includes the two sided matching and package auction models as well as a simplified version of a labor market model of alexander kelso and vincent p crawford 1982 as special cases they introduce the substitutes condition of contracts which is an adaptation of the substitutability condition in the matching literature roth and marilda a oliveira sotomayor 1990 to matching with contracts they show that there exists a stable allocation if contracts are substitutes for hospitals and that a number of other results in matching generalize to problems with contracts they further claim that the substitutes condition on individual hospitals prefer ences is necessary to guarantee the existence of a stable allocation for all possible singleton preferences of others that is if contracts are not substitutes for a hospital then there exists a preference profile of other hospitals with single job openings and doctors such that there exists no stable allocation we show that this last claim of hatfield and milgrom 2005 does not hold in general the counterexample we present involves a hospital which has two different kinds of positions and the preferences of the hospital are a combination of preferences of these two positions while the substitutes condition does not hold for that hospital we adopt a technique developed by bettina klaus and flip klijn 2005 and show that there exists a stable allocation we then present the weak substitutes condition which we show is necessary to guarantee existence of stable allocations the modified result we present as well as the original contribu tion of hatfield and milgrom 2005 suggest a connection between the substitutes condition and stability 2

migration with endogenous moving costs we study a dynamic model of labor migration in which moving costs decrease with the number of migrants already settled in the destination this assumption is supported by sociological studies of migrant networks with endogenous moving costs migration occurs gradually over time once it starts it develops momentum and migratory flows may increase even as wage differentials narrow in addition migration tends to follow geographical channels and low moving cost individuals migrate first these patterns are consistent with historical evidence from the great black migration of 1915 1960 in the united states much of which cannot be reconciled with existing migration models excerpt

the optimal public provision of private goods abstract this paper sets out conditions for the optimal public provision of in kind transfers rules are derived governing their marginal and optimal use in the presence of linear taxes because of the difficulty of using these conditions to examine what impact optimal transfers would have on optimal tax systems a simple two good simulation model is used to illustrate the problem

optimal linear income taxation with general equilibrium effects on wages abstract the paper argues that the endogeneity of wages may make a considerable difference to optimal linear tax rates in this case there is not only the usual direct redistribution via the fiscal system but also the general equilibrium redistribution due to the change in wages depending on the elasticity of substitution of the production function and the labour supply elasticities these may be reinforcing or opposing it is shown that the general equilibrium effect may plausibly outweigh the direct effect so that net redistribution to the lower paid involves a wage subsidy financed by a lump sum tax

unraveling reduces mobility in a labor market gastroenterology with and without a centralized match the entry level market for american gastroenterologists was organized by a centralized clearinghouse from 1986 to 1996 before and since it has been conducted via a decentralized market in which appointment dates have unraveled to well over a year before the start of employment we find that both before and after the years in which the centralized clearinghouse was used gastroenterologists are less mobile and more likely to be employed at the same hospital in which they were internal medicine residents than when the clearinghouse was in use this suggests that the clearinghouse not only coordinates the timing of appointments but also increases the scope of the market compared to a decentralized market with early appointments

house allocation with existing tenants an equivalence abstract we analyze two mechanisms designed to eliminate inefficiencies in house allocation problems where there are both existing tenants and newcomers the first mechanism chooses the unique core allocation of a sister exchange economy constructed by endowing each existing tenant with her current house and each newcomer with a random vacant house the second mechanism chooses an ordering from a given distribution and determines the final outcome as follows assign the agents the best available house one at a time following their ordering in the queue and whenever an agent demands the house of an existing tenant who is still in the line modify the queue by inserting the existing tenant at the top whenever a loop of existing tenants forms assign each of them the house she demands and proceed we show that the first mechanism is equivalent to an extreme case of the second which favors the newcomers

on the optimal income taxation some further numerical results abstract using numerical calculations we show in the optimal income tax model that a realistic value for the elasticity of substitution between consumption and leisure 0 5 leads to conclusions different from some of those drawn by mirrlees 1971 and atkinson 1973 the marginal tax rates are not so low and the shape of the tax schedule is for a great majority of the population substantially nonlinear a new feature in our calculations is that both results come out without going to maximin as done by atkinson 1973 we study in special cases the locality of the zero limit of the marginal tax rate at the upper end of the ability distribution and we achieve a very definite conclusion this result is really very local we also present an interesting approximation result concerning the relationship between the level of the government revenue and the marginal tax rate for individuals with high ability an important methodological remark analogous to sen s critique on the ethical measures of inequality is made on the interpretation of optimal income tax calculations

the welfare effects of coordinated assignment evidence from the new york city high school match abstract coordinated single offer school assignment systems are a popular education reform we show that uncoordinated offers in nyc s school assignment mechanism generated mismatches one third of

survey measures of family decision processes for econometric analysis of schooling decisions in this article we consider the collection of novel subjective data on family processes of schooling decisions in particular we review recent progress on survey measurement of expectations information and locus of decision of american families within the context of secondary schooling and we discuss possible future developments by providing concrete examples from recent exploratory efforts we argue that collection of data on adolescents and parents perceptions of the available school options and the application and admission rules their subjective expectations about short and long term consequences of alternative choices and their assessments of the locus of decision making within families could greatly enhance economic modeling and contribute to effective econometric analysis of schooling decisions jel c83 d19 d79 d83 d84 i21 i26 j24

family attachment and the decision to move by race abstract blacks in the united states move less than whites despite having many characteristics that are commonly associated with high geographical mobility such as high unemployment low rate of home ownership low marriage rate and settlement in areas where unemployment is high we find that this puzzle can be explained by the effects of family ties both nuclear and extended families which we proxy using data from the university of michigan s psid the results are robust to different specifications and estimation techniques

strategyproof assignment by hierarchical exchange we give a characterization of the set of group strategyproof pareto optimal and reallocation proof allocation rules for the assignment problem where individuals are assigned at most one indivisible object without any medium of exchange although there are no property rights in the model the rules satisfying the above criteria imitate a trading procedure with individual endowments in which individuals exchange objects from their hierarchically determined endowment sets in an iterative manner in particular these assignment rules generalize gale s top trading cycle procedure the classical rule for the model in which each individual owns an indivisible good

affirmative action through minority reserves an experimental study on school choice abstract minority reserves are an affirmative action policy proposed by hafalir et al 2013 in the context of school choice in a laboratory experiment we find that adding minority reserves to the gs and ttc mechanisms has positive effects on stability but is quite disappointing in terms of efficiency also gs induces higher rates of truth telling by minority students and thus outclasses ttc

informal job search and black youth unemployment in this paper i analyze how young black and white unemployed jobseekers use various methods of search and the employment outcomes which result from their use the focus is on distinguishing informal search methods i e friends and relatives or direct application without referral from more formal ones in analyzing racial differences the results show that the two informal methods of search account for about 90 of the difference in employment probabilities between white and black youth this also accounts for 57 71 of the difference in unemployment rates between the two furthermore most of these results reflect differences in the ability of these methods to generate job offers as opposed to differences in search effort or job acceptance rates however our ability to explain these differences through personal family and household characteristics was generally quite limited this abstract was borrowed from another version of this item

chinese college admissions and school choice reforms a theoretical analysis each year approximately 10 million high school seniors in china compete for 6 million seats through a centralized college admissions system within the last decade many provinces have transitioned from a sequential to a parallel mechanism to make their admissions decisions in this study we characterize a parametric family of application rejection assignment mechanisms including the sequential deferred acceptance and parallel mechanisms in a nested framework we show that all of the provinces that have abandoned the sequential mechanism have moved toward less manipulable and more stable mechanisms we also show that existing empirical evidence is consistent with our theoretical predictions

reserve design unintended consequences and the demise of boston s walk zones we show that in the presence of admissions reserves the effect of the precedence order i e the order in which different types of seats are filled is comparable to the effect of adjusting reser

financing education using optimal redistributive taxation abstract in this article the joint use of an income tax and public provision of education as instruments to achieve the government s distributional objectives is considered individuals differ in innate labour productivity and in aptitude to acquire skills through education actual labour productivity depends on both innate skill and the amount of education received using a generalized version of the mirrlees tax problem that incorporates these features qualitative properties of an optimal tax schedule are investigated

a model of multiple equilibria in geographic labor mobility abstract we develop a model of double matching in the labor market and the social environment in order to explain different migration patterns in response to local economic shocks this approach explains the different behaviors of workers in different groups regions or countries in an endogenous way by showing the existence of multiple equilibria rather than in an exogenous manner by introducing ex ante regulations or unemployment benefits this model can also explain why individuals from some communities form sister communities in some cases and not in others

why do popular mechanisms lack efficiency in random environments we consider the problem of randomly assigning n indivisible objects to n agents recent research introduced a promising mechanism the probabilistic serial that has superior e ciency properties than the most common real life mechanism random priority on the other hand mechanisms based on gale s celebrated top trading cycles method have long dominated the indivisible goods literature with the exception of the present context thanks to their outstanding e ciency features we present an equivalence

il legal assignments in school choice in public school choice students with strict preferences are assigned to schools schools are endowed with priorities over students incorporating constraints from different applications priorities are often modelled as choice functions over sets of students it has been argued that the most desirable criterion for an assignment is stability there should not exist any blocking pair no student shall prefer some school to her assigned school and have higher priority than some student who got into that school or the school has an empty seat we propose a blocking notion where in addition it must be possible to assign the student to her preferred school we then define the following stability criterion for a set of assignments a set of assignments is legal if and only if any assignment outside the set is blocked with some assignment in the set and no two assignments inside the set block each other we show that under very basic conditions on priorities there always exists a unique legal set of assignments and that this set has a structure common to the set of stable assignments i it is a lattice and ii it satisfies the rural hospitals theorem the student optimal legal assignment is efficient and provides a solution for the conflict between stability and efficiency

comparing school choice mechanisms by interim and ex ante welfare recent work has highlighted welfare gains from the use of the boston mechanism over deferred acceptance da in school choice problems in particular finding that when cardinal utility is taken into account boston interim pareto dominates da in certain incomplete information environments with no school priorities we show that these previous interim results are not robust to the introduction of weak priorities however we partially restore the earlier results by showing that from an ex ante utility perspective the boston mechanism pareto dominates any strategyproof mechanism including da even allowing for arbitrary priority structures thus we suggest ex ante pareto dominance as a relevant criterion by which to compare school choice mechanisms this criterion may be of particular interest to school districts as they can be thought of as social planners whose goal is to maximize the overall ex ante welfare of the students

leveling the playing field sincere and sophisticated players in the boston mechanism empirical and experimental evidence suggests different levels of sophistication among families in the boston public school student assignment plan we analyze the preference revelation game induced by the boston mechanism with sincere players who report their true preferences and sophisticated players who play a best response we characterize the set of nash equilibrium outcomes as the set of stable matchings of a modified economy where sincere students lose priority to sophisticated students any sophisticated student weakly prefers her assignment under the pareto dominant nash equilibrium of the boston mechanism to her assignment under the recently adopted student optimal stable mechanism jel d82 i21

education and taxation policies in the presence of countervailing incentives i examine income taxation and education policy when the government cannot observe individual productivity and there exist conflicting incentives for individuals to understate and overstate their productivity in this setting i identify four possible equilibria and discuss the corresponding taxation education policy mix i show that no general restrictions on optimal taxation and education policy emerge in this environment but each equilibrium and corresponding policy package can be associated with a country on the basis of its relative income and preference for redistribution

imperfect information markets and public provision of education abstract it is shown that recent models of public provision of education overstate the argument against a free market in education with complete information income taxation can render a market irrelevant but the paper also considers examples where a free market in education is necessary even with public provision

group strategyproof cost sharing the role of indifferences every agent reports his willingness to pay for one unit of a good a mechanism allocates goods and cost shares to some agents we characterize the group strategyproof gsp mechanisms under two alternative continuity conditions interpreted as tie breaking rules with the maximalist rule max an indifferent agent is always served with the minimalist rule min an indifferent agent does not get a unit of the good gsp and max characterize the cross monotonic mechanisms these mechanisms are appropriate whenever symmetry is required on the other hand gsp and min characterize the sequential mechanisms these mechanisms are appropriate whenever there is scarcity of the good our results are independent of an underlying cost function they unify and strengthen earlier results for particular classes of cost functions

family values and the regulation of labor flexible labor markets requires geographically mobile workers to be e cient otherwise rms can take advantage of the immobility of workers and extract monopsony rents in cultures with strong family ties moving away from home is costly thus individuals with strong family ties rationally choose regulated labor markets to avoid moving and limiting the monopsony power of rms even though regulation generates lower employment and income empirically we do nd that individuals who inherit stronger family ties are less mobile have lower wages are less often employed and support more stringent labor market regulations there are also positive cross country correlations between the strength of family ties and labor market rigidities finally we nd positive correlations between labor market rigidities at the beginning of the twenty rst century and family values prevailing before world war ii which suggests that labor market regulations have deep cultural roots

group strategy proofness in private good economies many salient rules to allocate private goods are not only strategyproof but also group strategy proof in appropriate domains of definition hence diminishing the traditional conflict between incentives and efficiency that is so for solutions to matching division cost sharing house allocation and auctions in spite of the substantive disparity between these cases in a general framework encompassing all of them we prove that the equivalence between the two forms of strategy proofness is due to an underlying common structure that transcends the many differences between the contexts and the mechanisms for which it holds jel c78 d44 d63 d71 d82

the combinatorial assignment problem approximate competitive equilibrium from equal incomes this paper proposes a new mechanism for combinatorial assignment for example assigning schedules of courses to students based on an approximation to competitive equilibrium from equal incomes ceei in which incomes are unequal but arbitrarily close together the main technical result is an existence theorem for approximate ceei the mechanism is approximately efficient satisfies two new criteria of outcome fairness and is strategyproof in large markets its performance is explored on real data and it is compared to alternatives from theory and practice all other known mechanisms are either unfair ex post or manipulable even in large markets and most are both manipulable and unfair

on the operation of multiple matching markets abstract we provide a new perspective on how to operate matching markets when there are many types of markets our finding is that the market wise adaptation of strategy proof and non wasteful rules yields a strategy proof rule with the following efficiency property no strategy proof rule pareto dominates the rule such rules are abundant as they include the market wise use of the well known priority based rules of the top trading cycles and the deferred acceptance this result gives theoretical support to the independent operation of markets observed in real life markets as well as our practice in market design that separately treats each market for its design

coalitional strategy proof house allocation abstract we consider house allocation without endowments we show that there is a unique maximal domain including all strict preferences on which efficiency and coalitional strategy proofness are compatible a preference relation belongs to the unique maximal domain if it is a strict descending ranking of houses to a certain house and indifference holds over it and the remaining houses we also show that on this domain mixed dictator pairwise exchange rules are the only rules satisfying efficiency and coalitional strategy proofness journal of economic literature classification numbers c78 d63 d71

matching with branch of choice contracts at the united states military academy branch selection is a key decision in a cadet s military career cadets at usma can increase their branch priorities at a fraction of slots by extending their service agreement this real life matching problem lls an important gap in market design literature although priorities fail a key substitutes condition the agent optimal stable mechanism is well dened and in contrast to the current usma mechanism it is fair stable and strategy proof adoption of this mechanism benets cadets and the army this new

strategy proof stochastic assignment abstract i study strategy proof assignment mechanisms where the agents reveal their preference rankings over the available objects a stochastic mechanism returns lotteries over deterministic assignments and mechanisms are compared according to first order stochastic dominance i show that non wasteful strategy proof mechanisms are not dominated by strategy proof mechanisms however non wastefulness is highly restrictive when the mechanism involves randomization in fact the random priority mechanism i e the random serial dictatorship and a recently adopted school choice mechanism deferred acceptance with random tie breaking are wasteful i find that both these mechanisms are dominated by strategy proof mechanisms in general strategy proof improvement cannot be due to merely reshuffling objects and therefore must involve assigning more objects

incentives in the probabilistic serial mechanism abstract the probabilistic serial mechanism bogomolnaia and moulin 2001 9 is ordinally efficient but not strategy proof we study incentives in the probabilistic serial mechanism for large assignment problems we establish that for a fixed set of object types and an agent with a given expected utility function if there are sufficiently many copies of each object type then reporting ordinal preferences truthfully is a weakly dominant strategy for the agent regardless of the number of other agents and their preferences the non manipulability and the ordinal efficiency of the probabilistic serial mechanism support its implementation instead of random serial dictatorship in large assignment problems

what parents want school preferences and school choice we investigate parents preferences for school attributes in a unique data set of survey administrative census and spatial data using a conditional logit incorporating characteristics of households schools and home school distance we show that most families have strong preferences for schools academic performance parents also value schools socio economic composition and distance which may limit the potential of school choice to improve academic standards most of the variation in preferences for school quality across socio economic groups arises from differences in the quality of accessible schools rather than differences in parents preferences although more advantaged parents have stronger preferences for academic performance

cardinal bayesian allocation mechanisms without transfers abstract in allocating goods with no use of monetary transfers random allocation mechanisms can be designed in order to elicit information on preference intensities i study the nontransfer allocation of two ex ante identical objects under bayesian incentive compatibility with symmetric agents and independent private valuations i find the ex ante utilitarian optimal mechanism in which the probability of receiving a specified object is used as numeraire to purchase probability units of the other object i characterize this mechanism as an appropriate combination of lotteries auctions and insurance the latter element ensures that efficient auctions are feasible if the problem is constrained to guarantee exactly one object per agent then the optimal mechanism uses no information other than the agents ordinal preferences

strategy proofness and stability of the boston mechanism an almost impossibility result abstract public school systems generally use one of the three competing mechanisms the boston mechanism the deferred acceptance mechanism and the top trading cycle mechanism for assigning students to specific schools although the literature generally claims that the boston mechanism is pareto efficient but neither stable nor strategy proof this study delineates a subset of school priority structures for which it fulfills all three criteria we show that the boston mechanism is stable if and only if it is strategy proof if and only if the priority structure is strongly acyclic however we find that the condition of strong acyclicity is nearly impossible to satisfy any priority structure is quasi cyclic whenever there are two schools whose admission quotas are less than the number of students seeking admission

an experimental study on decentralized networked markets abstract we design a laboratory experiment to investigate matching in a decentralized market of deferred acceptance agents are undifferentiated and may have multiple partners their payoff depends on who they match with the experiment is designed in such a way that a stable configuration exists but cannot be eyeballed by the participants due to the computational complexity of the game in spite of this subjects are remarkably good at reaching a stable match even when the payoffs of others are not publicly observed more information does however speed up convergence thanks to self censoring we trace irrational matching choices mostly to two sources the tendency of over think in a setting where strategic thinking is not necessary and the reluctance to accept matching offers from those who have been disloyal in the past

demand analysis using strategic reports an application to a school choice mechanism several school districts use assignment systems that give students an incentive to misrepresent their preferences we find evidence consistent with strategic behavior in cambridge such strategizing can complicate preference analysis this paper develops empirical methods for studying random utility models in a new and large class of school choice mechanisms we show that preferences are non parametrically identified under either sufficient variation in choice environments or a preference shifter we then develop a tractable estimation procedure and apply it to cambridge estimates suggest that while 82 of students are assigned to their stated first choice only 72 are assigned to their true first choice because students avoid ranking competitive schools assuming that students behave optimally the immediate acceptance mechanism is preferred by the average student to the deferred acceptance mechanism by an equivalent of 0 08 miles the estimated difference is smaller if beliefs are biased and reversed if students report truthfully

priorities in school choice the case of the boston mechanism in barcelona abstract the boston mechanism is a school allocation procedure that is widely used around the world and has been criticized for its incentive problems in order to resolve overdemands for a given school most often priority is given to families living in the neighborhood of the school using a very rich data set on school applications for the case of the boston mechanism in barcelona we exploit an unexpected change in the definition of neighborhood this change allows us to identify that a large fraction of families systematically ranks first high priority schools neighborhood schools in this case additional data on school enrollment decisions and census data shows that some seemingly unsophisticated parents are high income families that can rank hard to get schools because they can afford the outside option of a private school in case they do not get in this sheds light on important inequalities beyond parents lack of sophistication found in the literature

structural estimation of a model of school choices the boston mechanism vs its alternatives we model household choice of schools under the boston mechanism bm and develop a new method applicable to a broad class of mechanisms to fully solve the choice problem even if it is infeasible

on responsiveness of top trading cycles mechanism to priority based affirmative action abstract in school choice priority based affirmative action favors minority students by means of promoting their priority ranking at schools this paper investigates the responsiveness of the top trading cycles mechanism to priority based affirmative action when schools priority structure satisfies a certain acyclicity condition when schools priority under the problem without affirmative action satisfies virtual homogeneity condition a weak responsiveness result is obtained

top trading with fixed tie breaking in markets with indivisible goods abstract we study markets with indivisible goods where monetary compensations are not possible each individual is endowed with an object and a preference relation over all objects when preferences are strict gale s top trading cycles algorithm finds the unique core allocation when preferences are not necessarily strict we use an exogenous profile of tie breakers to resolve any ties in individuals preferences and apply gale s top trading cycles algorithm for the resulting profile of strict preferences we provide a foundation of these simple extensions of gale s top trading cycles algorithm from strict preferences to weak preferences we show that gale s top trading cycles algorithm with fixed tie breaking is characterized by individual rationality strategy proofness weak efficiency non bossiness and consistency our result supports the common practice in applications to break ties in weak preferences using some fixed exogenous criteria and then to use a good and simple rule for the resulting strict preferences

resolving conflicting preferences in school choice the boston mechanism reconsidered the boston mechanism is among the most popular school choice pro cedures in use yet the mechanism has been criticized for its poor incentive and welfare performances which led the boston public schools to recently replace it with gale and shapley s deferred acceptance algorithm henceforth da the da elicits truthful revelation of ordinal preferences whereas the boston mechanism does not but the latter induces participants to reveal their cardinal preferences i e their relative preference intensities whereas the former does not we show that cardinal preferences matter more when families have similar ordinal preferences and schools have coarse priorities two common features of many school choice environ ments speci cally when students have the same ordinal preferences and schools have no priorities the boston mechanism pareto dominates the da in ex ante wel fare the boston mechanism may not harm but rather bene t participants who may not strategize well in the presence of school priorities the boston mechanism also tends to facilitate a greater access than the da to good schools by those lack ing priorities at those schools these results contrast with the standard view and cautions against a hasty rejection of the boston mechanism in favor of mechanisms such as the da

mistaken play in the deferred acceptance algorithm implications for positive assortative matching abstract recent literature has documented failures of truthful preference reporting in the strategy proof deferred acceptance algorithm i consider the implications of these strategic mistakes for a common welfare consideration the ability of the mechanism to sort the best students to the best schools i find that these mistakes have the potential to significantly help or significantly hinder sorting through this channel the presence of mistaken play may have widely varying welfare effects i discuss related considerations in the welfare evaluation of mistaken play in the deferred acceptance algorithm and the implications for nudges that correct these mistakes

ordinal versus cardinal voting rules a mechanism design approach abstract we consider the performance and incentive compatibility of voting rules in a bayesian environment agents have independent private values there are at least three alternatives and monetary transfers are prohibited first we show that in a neutral environment meaning alternatives are symmetric ex ante essentially any ex post pareto efficient ordinal rule is incentive compatible importantly however we can improve upon ordinal rules we show that we can design an incentive compatible cardinal rule which achieves higher utilitarian social welfare than any ordinal rule finally we provide numerical findings about incentive compatible cardinal rules that maximize utilitarian social welfare

welfare of naive and sophisticated players in school choice two main school choice mechanisms have attracted the attention in the liter ature boston and deferred acceptance da the question arises on the ex ante welfare implications when the game is played by participants that vary in terms of their strategic sophistication abdulkadiroglu che and yasuda 2011 have shown that the chances of naive participants getting into a good school are higher under the boston mechanism than under da and some naive participants are actually better o in this note we show that these results can be extended to show that under the veil of ignorance i e students not yet knowing their utility values all naive students may prefer to adopt the boston mechanism

recombinant estimation for normal form games with applications to auctions and bargaining abstract when analyzing economic games researchers frequently estimate quantities describing group outcomes such as the expected revenue in an auction for such applications we propose an improved statistical estimation technique called recombinant estimation the technique takes observations of players strategies and recombines them to compute all possible group outcomes that could have resulted from different player combinations in applications to an auction and a bargaining game the improved efficiency of our estimator is equivalent to increasing the sample size between 25 and 200 we discuss how to design experiments in order to utilize recombinant estimation we also discuss practical computational issues and provide software for computing estimates and standard errors

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