health expenditure growth looking beyond the average through decomposition of the full distribution explanations of growth in health expenditures have restricted attention to the mean we explain change throughout the distribution of expenditures providing insight into how expenditure growth and its explanation differ along the distribution we analyse dutch data on actual health expenditures linked to hospital discharge and mortality registers full distribution decomposition delivers findings that would be overlooked by examination of changes in the mean alone the growth rate of hospital expenditures is greatest at the middle of the distribution and is driven mainly by changes in the distributions of determinants pharmaceutical expenditures increase most rapidly at the top of the distribution and are mainly attributable to structural changes including technological progress making treatment of the highest cost cases even more expensive changes in hospital practice styles make the largest contribution of all determinants to increased spending not only on hospital care but also on pharmaceuticals suggesting important spill over effects

deciding between competition and collusion we develop an approach to identify and test for bid rigging in procurement auctions first we introduce a general auction model with asymmetric bidders second we study the problem of identie cation in our model we state a set of conditions that are both necessary and sufe cient for a distribution of bids to be generated by a model with competitive bidding third we discuss how to elicit a prior distribution over a e rm s structural cost parameters from industry experts given this prior distri bution we use bayes s theorem to compare competitive and collusive models of industry equilibrium finally we apply our methodology to a data set of bidding by construction e rms in the midwest the techniques we propose are not computationally demanding use e exible functional forms and can be programmed using most standard statistical packages

testing for asymmetric information in insurance markets the first goal of this paper is to provide a simple and general test of the presence of asymmetric information in contractual relationships within a competitive context we also argue that insurance data are particularly well suited to such empirical investigations to illustrate this claim we use data on contracts and accidents to investigate the extent of asymmetric information in the french market for automobile insurance using various parametric and nonparametric methods we find no evidence for the presence of asymmetric information in this market

martingales and arbitrage in securities markets with transaction costs abstract we derive the implications from the absence of arbitrage in dynamic securities markets with bid ask spreads the absence of arbitrage is equivalent to the existence of at least an equivalent probability measure that transforms some process between the bid and the ask price processes of traded securities into a martingale the martingale measures can be interpreted as possible linear pricing rules and can be used to determine the investment opportunities available in such an economy the minimum cost at which a contingent claim can be obtained through securities trading is its largest expected value with respect to the martingale measures journal of economic literature classification numbers g11 g12 g13 d52 and d90

health shocks and risk aversion we empirically assess whether a health shock influences individual risk aversion we use grip strength data to obtain an objective health shock indicator in order to account for the non random nature of our data regression adjusted matching is employed risk preferences are traditionally assumed to be constant however we find that a health shock increases individual risk aversion the finding is robust to a series of sensitivity analyses and persists for at least four years after the shock income changes do not seem to be the driving mechanism

counterfactual decomposition of changes in wage distributions using quantile regression we propose a method to decompose the changes in the wage distribution over a period of time in several factors contributing to those changes the method is based on the estimation of marginal wage distributions consistent with a conditional distribution estimated by quantile regression as well as with any hypothesized distribution for the covariates comparing the marginal distributions implied by different distributions for the covariates one is then able to perform counterfactual exercises the proposed methodology enables the identification of the sources of the increased wage inequality observed in most countries specifically it decomposes the changes in the wage distribution over a period of time into several factors contributing to those changes namely by discriminating between changes in the characteristics of the working population and changes in the returns to these characteristics we apply this methodology to portuguese data for the period 1986 1995 and find that the observed increase in educational levels contributed decisively towards greater wage inequality copyright 2005 john wiley sons ltd

procurement contracting with time incentives theory and evidence in public procurement social welfare often depends on how quickly the good is delivered a leading example is highway construction where slow completion inflicts a negative externality on commuters in response highway departments award some contracts using scoring auctions which give contractors explicit incentives for accelerated delivery we characterize efficient design of these mechanisms we then gather an extensive data set of highway projects awarded by the california department of transportation between 2003 and 2008 by comparing otherwise similar contracts we show that where the scoring design was used contracts were completed 30 40 faster and the welfare gains to commuters exceeded the increase in procurement costs using a structural model that endogenizes participation and bidding we estimate that the counterfactual welfare gain from switching all contracts from the standard design to the efficient apb design is nearly 22 of the total contract value 1 14 billion copyright 2011 oxford university press

auctioning incentive contracts this paper draws a remarkably simple bridge between auction theory and incentive theory it considers the auctioning of an indivisible project among several fi rms the firms have private information about their future cost at th e bidding stage and the selected firm ex post invests in cost reduct ion the authors show that 1 the optimal auction can be implemented by a dominant strategy auction that uses information about both the first bid and the second bid 2 the winner faces a linear incenti ve contract 3 the fixed transfer to the winner decreases with his announced expected cost and increases with the second lowest announce d expected cost and 4 the share of cost overruns borne by the winn er decreases with the winner s announced expected cost copyright 1987 by university of chicago press

moral hazard incentive contracts and risk evidence from procurement deadlines and late penalties are widely used to incentivize effort tighter deadlines and higher penalties induce higher effort but increase the agent s risk we model how these contract terms affect the work rate and time to completion in a procurement setting characterizing the efficient contract design using new micro level data on minnesota highway construction contracts that includes day by day information on work plans hours worked and delays we find evidence of ex post moral hazard contractors adjust their effort level during the course of the contract in response to unanticipated productivity shocks in a way that is consistent with our theoretical predictions we next build an econometric model that endogenizes the completion time as a function of the contract terms and the productivity shocks and simulate how commuter welfare and contractor costs vary across different terms and shocks accounting for the traffic delays caused by construction switching to a more efficient contract design would increase welfare by 22 5 of the contract value while increasing the standard deviation of contractor costs a measure of risk by less than 1 of the contract value

financial innovations and arbitrage pricing in economies with frictions revisited abstract existing literature points to the role of market frictions in providing motivations for financial innovations in this paper we study the effectiveness of the arbitrage pricing approach and the design and pricing of innovated securities in economies with restrictions on short sales in the process we also define the no arbitrage conditions that is appropriate for such economies the differences between our results and chen s 3 are pointed out when appropriate journal of economic literature classification numbers c61 g10 g12 g20

financial innovation and arbitrage pricing in frictional economies abstract frictional economies are fundamentally different from their frictionless counterparts for example in frictional economies the price function is sublinear and thus there will be incentives to innovate when decomposing existing securities and opening new markets innovators serve important economic functions such as allowing investors to obtain consumption at lower costs enabling investors to achieve better risk sharing and making the fundamental value of more payoffs observable in particular innovators serve these functions even when they introduce redundant securities that are not yet issued furthermore in frictional economies the replication based arbitrage valuation approach tends to overprice certain securities while underpricing others journal of economic literature classification numbers c61 g10 g12 g20

bidding for incomplete contracts an empirical analysis of adaptation costs abstract procurement contracts are often renegotiated because of changes that are required after their execution using highway paving contracts we show that renegotiation imposes significant adaptation costs reduced form regressions suggest that bidders respond strategically to contractual incompleteness and that adaptation costs are an important determinant of their bids a structural empirical model compares adaptation costs to bidder markups and shows that adaptation costs account for 7 5 14 percent of the winning bid markups from private information and market power the focus of much of the auctions literature are much smaller by comparison implications for government procurement are discussed jel d44 d82 d86 h57 l13 l74 r42

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

entry and competition effects in first price auctions theory and evidence from procurement auctions motivated by several interesting features of the highway mowing auction data from the texas department of transportation tdot we study three competing procurement auction models with endogenous entry our entry and bidding models provide several interesting implications for the first time we show that even within an independent private value paradigm as the number of potential bidders increases bidders equilibrium bidding behaviour can become less aggressive and the expected procurement cost may rise because the entry effect is always positive and may dominate the negative competition effect we then develop structural models of entry and bidding corresponding to the three models under consideration controlling for unobserved auction heterogeneity and use the recently developed semi parametric bayesian estimation method to analyse the data we select the model that best fits the data and use the corresponding structural estimates to quantify the entry effect and the competition effect with regard to the individual bids and the procurement cost copyright 2009 wiley blackwell

to build or not to build normative and positive theories of public private partnerships abstract this paper analyzes whether the two tasks of building infrastructures which are socially useful in providing public services and managing these assets should be bundled or not when performance contracts can be written both tasks should be performed altogether by the same firm if a better design of the infrastructure helps also to save on operating costs otherwise tasks should be kept apart and undertaken by different units in incomplete contracting environments we isolate conditions under which either the traditional form of public provision of services or the more fashionable public private partnership emerges optimally the latter dominates when there is a positive externality and the private benefits from owning assets are small enough finally we take a political economy perspective and study how incentive schemes are modified under the threat of capture of the decision makers much of the gains from bundling may be lost in this case

medical care costs how much welfare loss hardly a week goes by without a front page newspaper article on rising health care costs and the uninsured in this article i focus mainly on costs arguing that the issue has been somewhat misconceived while the level of medical care spending in the u s is a cause for concern the welfare losses associated with rises in that level of spending may not be as large as the public rhetoric can make them seem in fact cost containment may not be as urgent as is widely supposed and some proposed cost containment policies may result in welfare losses for the insured and even increase the number of uninsured

the provision of incentives in firms i ncentives are the essence of economics despite many wide ranging claims about their supposed importance there has been little empirical assessment of incentive provision for workers the purpose of this paper is to critically overview existing work on the provision of incentives since the interests of workers and their employers are not always aligned a large theoretical literature has emphasized how firms design compensation contracts to induce employees to operate in the firm s interest this literature has reached into many areas of compensation and has pointed to a multitude of different mechanisms that can be used to induce workers to act in the interests of their employers these include piece rates options discretionary bonuses promotions profit sharing efficiency wages deferred compensation and so on my objective here is to evaluate this literature in the light of a growing empirical literature on compensation where possible i will address the literature from two perspectives first an underlying assumption of this literature is that individuals respond to contracts that reward performance accordingly i consider whether agents behave in this way and whether these responses are always in the firm s interest second i address whether firms write contracts with these responses in mind in other words do contracts look like the predictions of the theory incentives are provided to workers

bid preference programs and participation in highway procurement auctions we use data from highway procurement auctions subject to california s small business preference program to study the effect of bid preferences on auction outcomes our analysis is based on an estimated model of firms bidding and participation decisions which allows us to evaluate the effects of current and alternative policy designs we show that incorporating participation responses significantly alters the assessment of preferential treatment policies

using cost observation to regulate firms the paper emphasizes the use of accounting data in regulatory or procurement contracts when the supplier 1 has superior information about the cost of the project and 2 invests in cost reduction the main result states that under risk neutrality the supplier announces an expected cost and is given an incentive contract linear in cost overruns this optimal contract moves toward a fixed price contract as the announced cost decreases an investment choice is then introduced and the use of a rate of return regulation is studied

effective securities in arbitrage free markets with bid ask spreads at liquidation a linear programming characterization abstract we consider a securities market with bid ask spreads at any period including liquidation although the minimum cost super replication problem is non linear we introduce an auxiliary problem that allows us to characterize no arbitrage via linear programming techniques we introduce the notion of effective new security and show that effectiveness restricts the no arbitrage bid and ask prices of a new security to the interval defined by the minimum cost problem we discuss in detail the cases in which the boundaries of this interval can be reached without violating no arbitrage

an econometric analysis of health care expenditure a cross section study of the oecd countries this paper is an empirical examination of the determinants of aggregate health care expenditure the paper presents a systematic analysis of relationships across 19 oecd countries showing the effects of aggregate income institutional and socio demographic factors on health care expenditure the results indicate that institutional factors of the health systems in addition to per capita gross domestic product gdp contribute significantly to the explanation of the health care expenditure variation between countries for example the way physicians in outpatient care are paid and the mixture of public private funding and inpatient outpatient care

reference health and the demand for medical care we propose that health in prior periods termed reference health is theoretically and empirically relevant to the demand for medical care to address non normality in the distributions of medical care spending consumption and health we use a conditional density estimator nested in a finite mixture framework we find that reference health can help explain the variation in spending among individuals with the same contemporaneous health particularly in the top tail of the spending distribution we demonstrate that omitting reference health understates the potential cost savings of healthy aging initiatives by 50 percent this article is protected by copyright all rights reserved

increasing competition and the winner s curse evidence from procurement we assess empirically the effects of the winner s curse which in common value auctions counsels more conservative bidding as the number of competitors increases first we construct an econometric model of an auction in which bidders preferences have both common and private value components and propose a new monotone quantile approach which facilitates estimation of this model second we estimate the model using bids from procurement auctions held by the state of new jersey for a large subset of these auctions we find that median procurement costs rise as competition intensifies in this setting then asymmetric information overturns the common economic wisdom that more competition is always desirable

optimal replication of options with transactions costs and trading restrictions this paper analyzes the strategy that minimizes the initial cost of replicating a contingent claim in a market with transactions costs and trading constraints the linear programming and two stage backward recursive models developed are applicable to the replication of convex as well as nonconvex payoffs and to a portfolio of options with different maturities the paper s formulation conveniently accounts for fixed and variable transactions costs lot size constraints and position limits on trading the article shows that in the presence of trading frictions it is no longer optimal to revise one s portfolio in each period at the optimum cash flows in excess of the desired ones may be generated the optimal policy trades off the curvature of the payoff that is generated against the terminal slack

aggregation and linearity in the provision of intertemporal incentives we consider the problem of providing incentives over time for an agent with constant absolute risk aversion the optimal compensation scheme is found to be a linear function of a vector of n accounts which count the number of times that each of the n kinds of observable events occurs the number n is independent of the number of time periods so the accounts may entail substantial aggregation in a continuous time version of the problem the agent controls the drift rate of a vector of accounts that is subject to frequent small random fluctuations the solution is as if the problem were the static one in which the agent controls only the mean of a multivariate normal distribution and the principal is constrained to use a linear compensation rule if the principal can observe only coarser linear aggregates such as revenues costs or profits the optimal compensation scheme is then a linear function of those aggregates the combination of exponential utility normal distributions and linear compensation schemes makes computations and comparative statics easy to do as we illustrate we interpret our linearity results as deriving in part from the richness of the agent s strategy space which makes it possible for the agent to undermine and exploit complicated nonlinear functions of the accounting aggregates

efficient trading strategies in the presence of market frictions we provide a price characterization of efficient contingent claims that is chosen by at least a rational agent in multiperiod economies with market frictions frictions include market incompleteness transaction costs short selling and borrowing costs we characterize the inefficiency cost of a trading strategy its required investment minus the largest amount necessary to obtain the same utility level and we propose a measure of portfolio performance we show that arbitrage bounds cannot be tightened based on efficiency without restricting preferences or endowments we observe common investment strategies becoming inefficient with market frictions and others rationalized by them in this article we characterize efficient contingent claims to future consumption consumption bundles in multiperiod economies with uncertainty taking a wide range of market frictions into account 1 such as dynamic market

are bid preferences benign the effect of small business subsidies in highway procurement auctions abstract bid preferences in procurement auctions allow firms from an identifiable group an advantage in bidding against unfavored firms while economic efficiency is expected to fall as a result of bid preferences government procurement costs may either increase or decrease depending on the competitive response of favored and unfavored firms this paper uses data from california auctions for road construction contracts where small businesses receive a 5 percent bid preference in auctions for projects using only state funds and no preferential treatment on projects using federal aid i show that while firms bidding behavior matches theoretical predictions procurement costs are 3 8 percent higher on auctions using preferences the higher procurement cost in preference auctions is attributed to reduced participation by lower cost large firms structural estimates of latent firm costs are then used to evaluate how efficiency and the division of surplus between firms and the government are impacted by bid preferences firm profits are 3 1 percent lower under bid preferences however this is overwhelmed by the efficiency loss due to reduced large firm participation the efficiency loss conditional on firm participation is estimated to represent around 0 1 percent of overall procurement costs including the adverse effect of preferences on the participation of large firms increases the estimated efficiency loss to 3 6 percent which represents 27 cents for each additional dollar awarded to small businesses through the program counterfactual simulations indicate that if participation were instead inelastic to bid preferences the 5 percent bid preference would be close to the optimal level

financial market structures revealed by pricing rules efficient complete markets are prevalent abstract it is well known that when an arbitrage free financial market is incomplete or has tradable financial assets with frictions there must be multiple risk neutral probability measures the main motivation for the present study is to elucidate what type of market structure usually emerges from pricing rules first we obtain that finitely generated pricing rules characterized by polytopes of probabilities capture the class of all finite arbitrage free financial markets that are potentially incomplete or subject to frictions affecting tradable assets next we provide a novel characterization of efficient securities and introduce related notions of market completeness that underlies pricing rules our main result shows that the class of efficient complete markets with bid ask spreads is the prevalent case revealed by finitely generated pricing rules

the changing distribution of male wages in the uk this paper uses microeconomic data from the u k family expenditure surveys fes and the general household surveys ghs to describe and explain changes in the distribution of male wages since the late 1970s wage inequality has risen very fast in the u k and this rise is characterized both by increasing education and age differentials we show that a large part of the changes in the u k can be summarized quite simply as increases in eduction differentials and a decline of growth of entry level wages which persist subsequently this fact we interpret as cohort effects we also show that like in the u s an important aspect of rising wage inequality is increased within group wage dispersion finally we use the ghs to evaluate the role of alternative education measures

health care is an individual necessity and a national luxury applying multilevel decision models to the analysis of health care expenditures health care is neither a necessity or a luxury it is both since the income elasticity varies with the level of analysis with insurance individual income elasticities are typically near zero while national health expenditure elasticities are commonly greater than 1 0 the debate over whether health care is or is not a luxury good arises primarily from the failure to specify levels of analysis clearly so as to distinguish variation within groups from variation between groups apparently contradictory empirical results are shown to be consistent with a simple nested multilevel model of health care spending