moral hazard adverse selection and health expenditures a semiparametric analysis theoretical models predict asymmetric information in health insurance markets may generate inefficient outcomes due to adverse selection and moral hazard however previous empirical research has found it difficult to disentangle adverse selection from moral hazard in health care consumption we propose a two step semiparametric estimation strategy to identify and estimate a canonical model of asymmetric information in health care markets with this method we can estimate a structural model of demand for health care we illustrate this method using a claims level data set with confidential information from a large self insured employer we find significant evidence of moral hazard and adverse selection

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

monopoly insurance under adverse selection when agents differ in risk aversion abstract this paper considers a profit maximizing monopolistic insurer who offers insurance to two types of risk averse agents in an environment where the uninsured position has the same distribution across types agents utility functions are private information and types are independently and identically distributed we prove that if there is no lower bound on liability and the types differ markedly in their attitudes to heavy losses the insurer can extract almost all rent by offering full insurance to agents who are more risk averse and two valued partial insurance to the others under limited liability separating insurance contracts have a similar structure but it may be impossible to approximate the first best unless the uninsured position is supported by two atoms insurance is provided to all agents journal of economic literature classification numbers d42 d82

the relation between price and marginal cost in u s industry a contradiction in a recent article in this journal hall 1988 examined productivity shocks at the industry level derived from constant returns to scale production functions in which firms were assumed to be competitive hall had two important conclusions first he showed that productivity shocks i e solow residuals were correlated with aggregate demand variables implying that the former are not exogenous impulses second his results implied that firms persistently charge prices above marginal costs making inappropriate the constant returns to scale competitive production function assumed in many theoretical frameworks because of the importance of hall s findings the article has led to many extensions evans 1992 confirms the empirical finding of significant correlations between productivity shocks and aggregate demand variables burnside eichenbaum and rebelo 1993 show that this correlation can be explained by introducing labor hoarding into a theoretical model with competitive firms and constant returns to scale production functions the markups above marginal cost are explained by eden and griliches 1991 and galeotti and schiantarelli 1991 by modifying the theoretical production function caballero and lyons 1992 using the hall data and methodology examine the possibility of external economies in the aggregate manufacturing production finally waldmann 199 1 argues in this journal that the

the welfare implications of moral hazard and adverse selection in competitive insurance markets i model a competitive insurance market with both moral hazard and adverse selection and analyze the effect on welfare when both problems are present simultaneously an examination of the interaction between these two problems leads to two hypotheses first the nature of the equilibrium contracts is such that each problem partially offsets the welfare loss associated with the other and second the degree to which this occurs increases as agents become more heterogeneous simulation results overwhelmingly support both hypotheses

the deadweight gain of insurance taxation when risky activities are optional abstract some risky activities are optional for example motoring participation in them is most attractive for good risks creating a tendency for advantageous selection in the associated insurance market taxing insurance consequently yields deadweight gains when type is hidden results are strengthened if optimism is present finally endogenising participation implies that the standard positive correlation test for the presence of policy relevant asymmetric information may fail

adverse selection commitment and renegotiation extension to and evidence from insurance markets with asymmetric information full commitment to long term contracts may permit markets to approach first best allocations however commitment can be undermined by opportunistic behavior notably renegotiation we reexamine commitment in insurance markets we present an alternative model which extends laffont and tirole s procurement model to address uncertainty and competition which involves semipooling in the first period followed by separation this and competing models e g single period models and no commitment models have different predictions concerning temporal patterns of insurer profitability a test using california data suggests that some automobile insurers use commitment to attract selective portfolios comprising disproportionate numbers of low risks

overconfidence and asymmetric information the case of insurance this paper contributes to the recent behavioral economics literature by showing that whether or not overconfidence changes qualitative predictions in asymmetric information markets may depend on the market structure itself we first show that overconfidence may overturn fundamental relations between observable variables in perfect competition asymmetric information insurance markets in monopolistic insurance markets in constrast we find that overconfidence may be observationally equivalent to variations in the risk composition of the economy our analysis provides a number of novel testable implications on i price heterogeneity within and across risk classes ii the relationship between ex post risk and insurance coverage iii the fact that a significant fraction of agents chooses to be uninsured and iv the relationship between underinsurance and age

multidimensional private information market structure and insurance markets we investigate whether selection based on multidimensional private information in risks and risk preferences can under different market structures result in a negative correlation between insurance coverage and ex post realization of risk we show that under perfect competition selection based on multidimensional private information does not result in the negative correlation property unless there is a sufficiently high loading factor however it is possible to generate the negative correlation property under monopoly when risk and risk preference types are sufficiently negative dependent we also clarify the connections between important concepts such as adverse advantageous selection and positive negative correlation property

comparing four models of aggregate fluctuations due to self fulfilling expectations abstract this paper compares four equilibrium business cycle models with increasing returns to scale production technologies that allow for aggregate fluctuations due to self fulfilling expectations necessary and sufficient conditions for the existence of stationary sunspot equilibria are derived numerical examples demonstrate that the degree of increasing returns necessary for the existence of stationary sunspot equilibria lies in the upper range of available empirical estimates the paper also shows that persistent fluctuations are not a necessary property of these four models when the only source of fluctuations is changes in people s expectations about the future path of the economy journal of economic literature classification numbers e32 d43

selection in insurance markets theory and empirics in pictures government intervention in insurance markets is ubiquitous and the theoretical basis for such intervention based on classic work from the 1970s has been the problem of adverse selection over the last decade empirical work on selection in insurance markets has gained considerable momentum this research finds that adverse selection exists in some insurance markets but not in others and it has uncovered examples of markets that exhibit advantageous selection a phenomenon not considered by the original theory and one that has different consequences for equilibrium insurance allocation and optimal public policy than the classical case of adverse selection advantageous selection arises when the individuals who are willing to pay the most for insurance are those who are the most risk averse and so have the lowest expected cost indeed it is natural to think that in many instances individuals who value insurance more may also take action to lower their expected costs drive more carefully invest in preventive health care and so on researchers have taken steps toward estimating the welfare consequences of detected selection and of potential public policy interventions in this essay we present a graphical framework for analyzing both theoretical and empirical work on selection in insurance markets this graphical approach provides both a useful and intuitive depiction of the basic theory of selection and its implications for welfare and public policy as well as a lens through which one can understand the ideas and limitations of existing empirical work on this topic

preference heterogeneity and insurance markets explaining a puzzle of insurance the textbook approach to insurance markets emphasizes the role of private information about risk in determining who purchases insurance in the classic adverse selection model of michael rothschild and joseph stiglitz 1976 individu als with higher expected claims buy more insur ance than those with lower expected claims who may be out of the market entirely this basic prediction of asymmetric information models of a positive correlation between insurance cov erage and accident occurrence has been shown to be robust to a variety of extensions to the stan

information technology and growth the rapid diffusion of information technology it is a direct consequence of the swift decline in the price of computer related equipment which has led to a vast and continuing substitution of it equipment for other forms of capital and labor this substitution generates substantial returns for the economic agents who undertake it investments and restructure their activities in order to increase the role of it there is little evidence however that substitution is accompanied by technical change as this term is used by economists while this appears highly paradoxical to technologists who think of substitution of a more it intensive mode of production for a less itintensive mode as a change in technology it is entirely consistent with the economic framework developed by robert m solow 1957 what do economists mean by technical change and how could this exclude the substitution of a more it intensive production process for one that is less it intensive substitution represents movement along a given production function while technical change corresponds to a shift in the production function substitution takes place if the introduction of computer intensive equipment produces benefits that are fully captured or internalized by the users of it and their suppliers technical change occurs only if more

health insurance without single crossing why healthy people have high coverage standard insurance models predict that people with high risks have high insurance coverage it is empirically documented that people with high income have lower health risks and are better insured we show that income differences between risk types lead to a violation of single crossing in an insurance model where people choose treatment intensity we analyse different market structures and show the following if insurers have market power the violation of single crossing caused by income differences and endogenous treatment choice can explain the empirically observed outcome our results do not rely on differences in risk aversion between types

understanding the large negative impact of oil shocks this paper oers a plausible explanation for the close link between oil prices and aggregate macroeconomic performance in the 1970s although this link has been well documented in the empirical literature standard economic models are not able to replicate this link when actual oil prices are used to simulate the models in particular standard models cannot explain the depth of the recession in 1974 75 and the strong revival in 1976 78 based on the oil price movements in that period this paper argues that a missing multiplier accelerator mechanism from standard models may hold the key

taylor rules and macroeconomic instability or how the central bank can preempt sunspot expectations this paper derives new results on the effects of employing taylor rules in economies that are subject to real market imperfections such as production externalities policies which respond to output movements can block sunspot equilibria that arise from the increasing returns the paper also finds that rules which should be chosen avoided in perfect market environments often yield ensure multiple unique rational expectations solutions in alternative settings therefore exact knowledge on the degree of market imperfection may be integral for robust policy advice

technological change and the stock market tobin s average q has usually been well above 1 but fell below 1 during 1974 1984 our model explains this pattern and reconciles it with unchanging aggregate investment the stock market value in the numerator of q reflects ownership of physical capital and knowledge but the denominator measures just physical capital therefore q is usually above 1 periodic arrivals of important new technologies such as the microprocessor in the 1970 s suddenly render old knowledge and capital obsolete causing the stock market to drop national accounts measures of physical capital miss this rapid obsolescence then q appears to drop below 1 jel e44 o3 o41

harmful competition in insurance markets there is a general presumption that competition is a good thing in this paper we show that competition in the insurance markets can be bad and that adverse selection is in general worse under competition than under monopoly the reason is that monopoly can exploit its market power to relax incentive constraints by cross subsidization between different risk types cream skimming behavior on the contrary prevents competitive firms from using implicit transfers in effect monopoly is shown to provide better coverage to those buying insurance but at the cost of limiting participation to insurance performing simulation for different distributions of risk we find that monopoly in general performs much better than competition in terms of the realization of the gains from trade across all traders in equilibrium

precise and efficient computation of the beveridge nelson decomposition of economic time series abstract this note shows how the beveridge nelson decomposition of economic time series can be precisely computed without the necessity for truncating infinite sums the algorithm includes those of beveridge and nelson 1981 and miller 1988 as special cases for particular models correcting an error in the latter

social security reform and national wealth recent trends in common stock prices suggest a distinction between increases in national net worth and flows of physical investment in this paper we present a simple overlapping generations model in which such differences can arise technological progress occurs exogenously yet firms own new technologies for a time we examine possible consequences for social security reform reform which increases private saving depletes part of its force raising the capitalized price of proprietary technologies a calibrated example suggests an increase in physical capital one third smaller than without inelastic factors both steady states and transition paths are considered

a dynamic analysis of the demand for health insurance and health care we find that asymmetric information is important for the uptake of supplementary private health insurance and health care utilization we use dynamic panel data models to investigate the sources of asymmetric information and distinguish short run selection effects into insurance from long run selection effects short run selection effects i e responses to shocks are adverse but small in size also long run effects driven by differences in for example preferences and risk aversion are small but we find some evidence for multidimensional asymmetric information for example mental health causes advantageous selection estimates of health care utilization models suggest that moral hazard is not important

the poor are twice cursed wealth inequality and inefficient credit market abstract this paper investigates the role of unobservable wealth differences on credit market equilibrium given there is also asymmetric information concerning effort preferences and choices in equilibrium poor but able entrepreneurs may subsidise the rich and incompetent or be excluded as a result investment may exceed or fall short of the optimal level low inequality may deliver conditions for perfect screening and an efficient level of investment the equilibrium with cross subsidisation is consistent with otherwise puzzling empirical observations

indeterminacy under constant returns to scale in multisector economies recently there has been a renewed interest in indeterminacy or alternatively put in the existence of a continuum of equilibria in dynamic economies that exhibit some market imperfections one of the primary concerns of this literature has been the empirical plausibility of indeterminacy which arises in markets with external effects or with monopolistic competition often coupled with some degree 10 of increasing returns

external effects in u s procyclical productivity abstract in this paper we highlight a new dimension of the aggregate procyclical productivity phenomenon we show that estimates of the degree of returns to scale are larger for manufacturing as a whole than for two digit industries since this difference must be due to factors that are only internalized at the most aggregate level we term it an external effect this result rules out explanations based on own input variation such as true increasing returns and unmeasured factor utilization tied to own activity as the sole explanations for aggregate procyclical productivity we explore several potential explanations of this external effect

an investigation of time preferences life expectancy and annuity versus lump sum choices can smoking harm long term saving decisions abstract we exploit the fact that israeli pension insurance policies do not take health conditions or smoking status into account in annuity pricing to investigate the potential effect of being a smoker on retirement payout choices contrary to the idea that smokers have higher discount rates and thus should prefer the lump sum option and even though the insurance pricing mechanism means that smokers would be offered the same annuity as nonsmokers all else equal we find that smokers do not prefer the lump sum option we offer and test several potential explanations for our findings illusions regarding life expectancy self control and advantageous selection

opec s oil exporting strategy and macroeconomic in stability aguiar conraria and wen 2008 argued that dependence on foreign oil raises the like lihood of equilibrium indeterminacy economic instability for oil importing countries we argue that this relation is more subtle the endogenous choices of prices and quantities by a cartel of oil exporters such as the opec can aect the directions of the changes in the likelihood of equilibrium indeterminacy we show that uctuations driven by self ful lling expectations under oil shocks are easier to occur if the cartel sets the price of oil but the re sult is reversed if the cartel sets the quantity of production these results oer a potentially interesting explanation for the decline in economic volatility i e the great moderation in oil importing countries since the mid 1980s when the opec cartel changed its market strategies from setting prices to setting quantities despite the fact that oil prices are far more volatile today than they were 30 years ago

health and mortality delta assessing the welfare cost of household insurance choice we develop a pair of risk measures health and mortality delta for the universe of life and health insurance products a life cycle model of insurance choice simplifies to replicating the optimal health and mortality delta through a portfolio of insurance products we estimate the model to explain the observed variation in health and mortality delta implied by the ownership of life insurance annuities including private pensions and long term care insurance in the health and retirement study for the median household aged 51 to 57 the lifetime welfare cost of market incompleteness and suboptimal choice is 3 2 of total wealth

multiple dimensions of private information evidence from the long term care insurance market we demonstrate the existence of multiple dimensions of private information in the long term care insurance market two types of people purchase insurance individuals with private information that they are high risk and individuals with private information that they have strong taste for insurance ex post the former are higher risk than insurance companies expect while the latter are lower risk in aggregate those with more insurance are not higher risk our results demonstrate that insurance markets may suffer from asymmetric information even absent a positive correlation between insurance coverage and risk occurrence the results also suggest a general test for asymmetric information

indeterminacy aggregate demand and the real business cycle abstract we show that under indeterminacy aggregate demand shocks are able to explain not only aspects of actual fluctuations that standard rbc models predict fairly well but also aspects of actual fluctuations that standard rbc models cannot explain such as the hump shaped trend reverting impulse responses to transitory shocks found in us output cogley and nason am econom rev 85 1995 492 the large forecastable movements and comovements of output consumption and hours rotemberg and woodford am econom rev 86 1996 71 and the fact that consumption appears to lead output and investment over the business cycle indeterminacy arises in our model due to capacity utilization and mild increasing returns to scale

externalities endogenous productivity and poverty traps abstract we present a version of the neoclassical model with an endogenous industry structure we construct a distribution of firms productivity that implies multiple steady state equilibria even with an arbitrarily small degree of increasing returns to scale while the most productive firms operate across all the steady states in a poverty trap less productive firms operate as well this results in lower average firm productivity and total factor productivity the distributions of employment by firm size across steady states are consistent with the empirical observation that poor countries have a higher fraction of employment in small firms than rich countries differences in output and total factor productivity across steady states are increasing in the degree of returns to scale the capital share and the frisch elasticity of labor supply

more health care utilization with more insurance coverage evidence from a latent class model with german data we analyse the impact of optional deductibles private supplementary health insurance and income on the demand for health care utilization measured as the number of physician visits with data from the german socio economic panel soep with a set of newly available variables for the years 2002 2004 and 2006 that measure individual health more accurately and including risk attitudes towards health we find that possible endogeneity of the insurance choice is not a problem a latent class approach that takes into account the panel structure of the data reveals that especially individuals who have few doctor visits the low users respond strongest to insurance status and income in this group we find that more insurance increases the demand for physician visits and there is a pro rich inequity in health care utilization no such effects are found for the high users

asymmetric information in insurance general testable implications several recent articles on empirical contract theory and insurance have tested for a positive correlation between coverage and ex post risk as predicted by standard models of pure adverse selection or pure moral hazard we show here that the positive correlationproperty can be extended to general setups competitive insurance markets and cases where risk aversion is public we test our results on a french dataset our tests confirm that the estimated correlation is positive they also suggest the presence of market power

optimal risk sharing under adverse selection and imperfect risk perception the present paper thoroughly explores second best efficient allocations in an insurance economy with adverse selection we start with a natural extension of the classical model assuming less than perfect risk perception we characterize the con straints on efficient redistribution and we summarize the incidence of incentives on the economy with the notions of weak and strong adverse selection finally we show in what sense improving risk perception enhances welfare a typical situation where the risk perception of the insurer and that of policy holders differ is one in which each party knows something that the other does not the insurer may correctly assess the impact on risk of an individual s character istics without observing them all whereas policyholders may know all their characteristics without relating them correctly to their risks these simple obser vations call for a modelling of imperfect risk perception and adverse selection

insurance induced moral hazard a dynamic model of within year medical care decision making under uncertainty health insurance may lead individuals to overconsume medical care many studies explore this moral hazard using models that aggregate medical care decisions up to the annual level using employer employee matched data from the medical expenditure panel survey meps i estimate moral hazard using a dynamic model of within year medical care consumption that allows for endogenous health transitions variation in medical care prices and individual uncertainty within a health insurance year i then estimate moral hazard under a second set of conditions that are consistent with the assumptions of most annual decision making models the within year decision making model produces a moral hazard estimate that is 19 2 larger than the alternative model i highlight the importance of controlling for within year dynamics in a model of medical care consumption using a counterfactual policy simulation that implements the individual mandate provision of the 2010 patient protection and aordable care act i nd that full implementation of the policy decreases the percentage of uninsured individuals in the population being analyzed from 11 8 to 6 0 furthermore when all uninsured individuals are forced into coverage their predicted annual medical care expenditure increases by 45 5

advantageous selection in insurance markets this article reverses the standard conclusion that asymmetric information plus competition results in insufficient insurance provision risk tolerant individuals take few precautions and are disinclined to insure but they are drawn into a pooling equilibrium by the low premiums created by the presence of safer more risk averse types taxing insurance drives out the reckless clients allowing a strict pareto gain this result depends on administrative costs in processing claims and issuing policies as does the novel finding of a pure strategy partial pooling subgame perfect nash equilibrium in the insurance market copyright 2001 by the rand corporation

do bad risks know it experimental evidence on optimism and adverse selection abstract subjects who overestimate their performance in experimental tasks unrelated to travel are less willing to insure against failing in the task and also less inclined to buy travel insurance this suggests intrinsic optimism influences insurance demand and diminishes adverse selection

experimental identification of asymmetric information evidence on crop insurance in the philippines abstract i study asymmetric information in crop insurance in the philippines using a two level randomized field experiment and incentivized preference elicitation in this first experimental study of moral hazard in non health insurance preventable damages double on randomly insured plots among farmers with high trust in the insurance provider farmers prefer insurance on plots that are at risk of floods and crop diseases a sign of classic adverse selection and plots that are far away from home a sign of selection on anticipated moral hazard behavior resulting in 72 higher payouts on preferred plots overcoming these challenges requires leveraging new technologies

adverse selection in annuity markets evidence from the british life annuity act of 1808 abstract we study adverse selection using data from an 1808 act of british parliament that effectively opened a market for life annuities our analysis indicates significant selection effects the evidence for adverse selection is strongest for a sub sample of annuitants whose annuities were purchased by profit seeking speculators a sub sample in which advantageous selection resulting from multi dimensional heterogeneity is unlikely to have been significant these results support the view that adverse selection can be masked by advantageous selection in empirical studies of standard insurance markets

preference heterogeneity and selection in private health insurance the case of australia a basic prediction of theoretical models of insurance is that if consumers have private information about their risk of suffering a loss there will be a positive correlation between risk and the level of insurance coverage we test this prediction in the context of the market for private health insurance in australia despite a universal public system that provides comprehensive coverage for inpatient and outpatient care roughly half of the adult population also carries private health insurance the main benefit of which is more timely access to elective hospital treatment like several studies on different types of insurance in other countries we find no support for the positive correlation hypothesis because strict underwriting regulations create strong information asymmetries this result suggests the importance of multi dimensional private information additional analyses suggest that the advantageous selection observed in this market is driven by the effect of risk aversion the ability to make complex financial decisions and income

the role of preference shocks and capital utilization in the great depression the article examines the proposition that preference shocks play a central role in our understanding of the great depression i identify a series of unusually large negative shocks that destabilized the u s economy during the 1930s when the artificial economy is paired with variable capital utilization and mildly increasing returns to scale in production it is able to account for most of the decline in economic activity and it predicts a tepid recovery

observing unobservables identifying information asymmetries with a consumer credit field experiment information asymmetries are important in theory but difficult to identify in practice we estimate the presence and importance of hidden information and hidden action problems in a consumer credit market using a new field experiment methodology we randomized 58 000 direct mail offers to former clients of a major south african lender along three dimensions i an initial offer interest rate featured on a direct mail solicitation ii a contract interest rate that was revealed only after a borrower agreed to the initial offer rate and ii a dynamic repayment incentive that was also a surprise and extended preferential pricing on future loans to borrowers who remained in good standing these three randomizations combined with complete knowledge of the lender s information set permit identification of specific types of private information problems our setup distinguishes hidden information effects from selection on the offer rate via unobservable risk and anticipated effort from hidden action effects via moral hazard in effort induced by actual contract terms we find strong evidence of moral hazard and weaker evidence of hidden information problems a rough estimate suggests that perhaps 13 to 21 of default is due to moral hazard asymmetric information thus may help explain the prevalence of credit constraints even in a market that specializes in financing high risk borrowers

genetic adverse selection evidence from long term care insurance and huntington disease abstract individual personalized genetic information is increasingly available leading to the possibility of greater adverse selection over time particularly in individual payer insurance markets we use data on individuals at risk for huntington disease hd a degenerative neurological disorder with significant effects on morbidity to estimate adverse selection in long term care insurance we find strong evidence of adverse selection individuals who carry the hd genetic mutation are up to 5 times as likely as the general population to own long term care insurance this finding is supported both by comparing individuals at risk for hd to those in the general population and by comparing across tested individuals in the hd risk population with and without the hd mutation

are housing bubbles contagious a case study of las vegas and los angeles home prices this paper asks whether speculative house price pressure in an economic center can spill into related housing markets in other words are bubbles contagious i develop a theoretical model that allows for speculative price appreciation to spread from one market to another i estimate an error correction model using quarterly housing data for las vegas and los angeles and fundamental market variables from 1978 quarter 2 through 2008 quarter 1 las vegas prices show significant persistence and adjust slowly to disequilibrium contagious price and income growth from the los angeles market sustained by naive expectations contributed to the bubble that formed in las vegas

moral hazard and selection among the poor evidence from a randomized experiment not only does economic theory predict high risk individuals to be more likely to purchase insurance but insurance coverage is also thought to crowd out precautionary activities in spite of stark theoretical predictions there is conflicting empirical evidence on adverse selection and evidence on ex ante moral hazard is very scarce using data from the seguro popular experiment in mexico this paper documents patterns of selection on observables into health insurance as well as the existence of non negligible ex ante moral hazard more specifically the findings indicate that i agents in poor self assessed health prior to the intervention have all else equal a higher propensity to take up insurance and ii insurance coverage reduces the demand for self protection in the form of preventive care curiously however individuals do not sort based on objective measures of their health

venture capital and the macroeconomy i develop a model of venture capital vc intermediation that quantitatively explains central empirical facts about vc activity and can evaluate its macroeconomic relevance the impact of vc backed innovations is significantly larger than suggested by observed aggregate venture exit valuations even after accounting for large exposures to systematic and uninsurable idiosyncratic risks the risk properties of venture capital play a quantitatively important role in both explaining empirical regularities and shaping the value of ventures contributions to economic growth the model is analytically tractable and yields exact solutions despite the presence of matching frictions imperfect risk sharing and endogenous growth received january 16 2018 editorial decision november 7 2018 by editor stijn van nieuwerburgh

indeterminacy home production and the business cycle a calibrated analysis abstract in this paper i present a business cycle model with one market sector that produces a standard good and another that produces a non market or home good the model can have multiple equilibria and therefore cycles driven only by self fulfilling expectations with low externalities to market production in particular an upward sloping aggregate labor demand as e g in farmer and guo j economic theory 63 1994 42 72 is not required for indeterminacy the effect of technology shocks is also studied in all cases the time series that are generated have properties that are comparable to the real us postwar series

evidence on adverse selection equilibrium signaling and cross subsidization in the insurance market the configuration of equilibrium in the market for automobile collision insurance is examined empirically by representing the premium deductible menu and the demand function as a standard hedonic system using contractual data from a representative insurer we estimate a reduced form hedonic premium equation and the inverse of the marginal bid equation for insurance coverage the data reveal an equilibrium with adverse selection and market signaling but lead us to reject the hypothesis that high risks receive contracts subsidized by low risks

moral hazard insurance claims and repeated insurance contracts the paper develops a simple model of repeated automobile insurance contracts providing a framework for analyzing changes in aggregate insurance data in periods of changes that affect driver incentives experience rating of premiums gives drivers an incentive to exert effort to avoid accidents ex ante moral hazard and an incentive to hide accidents ex post moral hazard the empirical analysis using data from the competitive insurance markets in ontario and alberta over a period of major legislative changes in ontario suggests that much of the recent decline in accidents in ontario was due to an increased incentive to hide accidents jel classification d 12 d82 hasard moral reclamations d assurance et contrats d assurance renouveles le texte developpe un modele simple de contrats d assurance automobile renouveles fournissant un cadre d analyse des donnees d assurance agregees dans des periodes de changement qui affectent les incitations des chauffeurs un regime de primes cotees selon l experience donne aux chauffeurs une incitation a faire des efforts pour eviter les accidents hasard moral ex ante et une incitation a cacher qu il y a eu accident hasard moral ex post l analyse empirique utilisant les donnees recueillies dans les marches d assurance con currentiels de l ontario et de l alberta pour une periode au cours de laquelle il y a eu des changements legislatifs majeurs en ontario suggere qu une bonne partie du declin des accidents enregistre en ontario a ete attribuable a une incitation accrue a cacher les accidents

false diagnoses pitfalls of testing for asymmetric information in insurance markets established tests for asymmetric information in insurance markets are examined the most commonly used that information is symmetric if high and low cover contracts have the same loss rate is inconsistent with standard assumptions that imply that under symmetric information all contracts o er full cover incomplete cover and symmetric information can be reconciled if there are claim processing costs but now existing tests fare badly partly due to the divergence between marginal and average selection effects ignoring the nature of loading factors may cause recent studies to mismeasure the welfare costs of asymmetric information but these problems are remedial

aggregate returns to scale and embodied technical change theory and measurement using stock market data abstract we develop a new general equilibrium growth accounting framework that features increasing returns to scale imperfect competition and incorporates technological revolutions into the description of technical progress we propose a way to tell apart revolutionary changes in technology and incremental innovations using stock market data we use our framework to jointly estimate the overall embodied tfp change during 1953 1995 and the aggregate output elasticity we find that the it revolution raised the aggregate tfp level by about 20 we suggest a 1 09 1 11 range for the aggregate returns to scale

estimating welfare in insurance markets using variation in prices we provide a graphical illustration of how standard consumer and producer theory can be used to quantify the welfare loss associated with inefficient pricing in insurance markets with selection we then show how this welfare loss can be estimated empirically using identifying variation in the price of insurance such variation together with quantity data allows us to estimate the demand for insurance the same variation together with cost data allows us to estimate how insurers costs vary as market participants endogenously respond to price the slope of this estimated cost curve provides a direct test for both the existence and the nature of selection and the combination of demand and cost curves can be used to estimate welfare we illustrate our approach by applying it to data on employerprovided health insurance from one specific company we detect adverse selection but estimate that the quantitative welfare implications associated with inefficient pricing in our particular application are small in both absolute and relative terms

imitation costs and patents an empirical study it has long been recognised that the costs of imitating new products have an important effect on the incentives for innovation in a market economy as arrow i962 and others have pointed out if firms can imitate an innovation at a cost that is substantially below the cost to the innovator of developing the innovation there may be little or no incentive for the innovator to carry out the innovation in their discussions of the innovation process economists frequently have called attention to the major role played by the costs of imitation but there has been little or no attempt to measure these costs to test various hypotheses concerning the factors influencing them or to estimate their effects in this paper we report some findings of what seems to be the first study of this topic in addition we present data regarding the effects of patents on imitation costs and on the rate of innovation

derivative ideas and the value of intangible assets we build a general equilibrium model where growth is driven by two invention types fundamental ideas that cause creative destruction and derivative ideas that enhance the value of existing inventions the model provides a new mapping from microeconomic patent data to aggregate total factor productivity growth and the aggregate value of privately owned knowledge we show how to measure the frequency of derivative ideas and the rate of creative destruction we estimate that derivative ideas account for 70 80 of all patents and their presence more than doubles the value of knowledge capital relative to what the measured innovation rate might otherwise imply

an empirical examination of information barriers to trade in insurance this paper uses direct evidence to evaluate whether asymmetric information is a barrier to trade in the largest market for private insurance in the world life insurance we report several findings that seem difficult to reconcile with the conventional theory of insurance under asymmetric information we conjecture that sellers may know their costs of production better than consumers in this market as in those for most other products

news about aggregate demand and the business cycle abstract the plausibility of expectations driven cyclical fluctuations in an otherwise standard one sector real business cycle model with variable capital utilization and mild increasing returns to scale in production is examined due to a dominating wealth effect our model is able to generate qualitatively as well as quantitatively realistic aggregate fluctuations driven by news impulses to future consumption demand or government spending on goods and services when the economy is subject to anticipated total factor productivity or investment specific technology shocks the relative strength of the intertemporal substitution effect needs to be enhanced for our model to exhibit positive macroeconomic co movement and business cycle statistics that are consistent with the data

the life insurance market asymmetric information revisited abstract this paper finds evidence for the presence of asymmetric information in the life insurance market a conclusion contrasting with the existing literature in particular we find a significant and positive correlation between the decision to purchase life insurance and subsequent mortality conditional on risk classification individuals who died within a 12 year time window after a base year were 19 more likely to have taken up life insurance in that base year than were those who survived the time window moreover as might be expected when individuals have residual private information we find that the earlier an individual died the more likely she was to have initially bought insurance the primary factor driving the difference between our and the prior literature s findings is that we focus on a sample of potential new buyers rather than on the entire cross section to address the sample selection problem induced by potential mortality differences between those with and those without coverage

incentive and selection effects of medigap insurance on inpatient care the medicare program which provides insurance coverage to the elderly in the united states does not protect them fully against high out of pocket costs for this reason private supplementary insurance named medigap has been available to cover medicare gaps this paper studies how medigap affects the utilization of inpatient care separating the incentive and selection effects of supplementary insurance for this purpose we use two alternative estimation methods a standard recursive bivariate probit and a discrete multivariate finite mixture model we find that estimated incentive effects are modest and quite similar across models there seems to be very significant selection with the presence of both adversely and advantageously selected individuals stemming from the multidimensional nature of residual heterogeneity

long run implications of investment specific technological change an attempt is made to disentangle its effects from the more traditional hicksneutral form of technological progress the balanced growth path for the model is characterized and calibrated to u s national income and product account nipa data the quantitative analysis suggests that investment specific technological change accounts for the major part of growth jel e13 030 041 047

estimating risk preferences from deductible choice we develop a structural econometric model to estimate risk preferences from data on deductible choices in auto insurance contracts we account for adverse selection by modeling unobserved heterogeneity in both risk claim rate and risk aversion we find large and skewed heterogeneity in risk attitudes in addition women are more risk averse than men risk aversion exhibits a u shape with respect to age and proxies for income and wealth are positively associated with absolute risk aversion finally unobserved heterogeneity in risk aversion is greater than that of risk and as we illustrate has important implications for insurance pricing

regional income fluctuations common trends and common cycles this paper investigates trend and cycle dynamics in per capita income for the major u s regions during the 1956 1995 period cointegration and serial correlation common features information are used in jointly decomposing the series into trend and cycle components we find considerable differences in the volatility of regional cycles controlling for differences in volatility we find a great deal of comovement in the cyclical response for all regions but the far west possible sources underlying differences in regional cycles are explored such as the share of a region s income accounted for by manufacturing defense spending as a proportion of a region s income oil price shocks and the stance of monetary policy somewhat surprisingly we find that the share of manufacturing in a region seems to account for little of the variation in regional cycles relative to national cycles but manufacturing share differentially affects trend growth for four of the seven regions studied

synchronisation and commonalities in metropolitan housing market cycles this paper examines the degree of commonalities present in the cyclical behaviour of the eight largest metropolitan housing markets in australia using two techniques originally proposed in the business cycle literature we firstly consider the degree of synchronisation present and secondly decompose the series into their permanent and cyclical components both empirical approaches reveal similar results sydney and melbourne are closely related to each other and are relatively segmented from the smaller metropolitan areas in contrast there is substantial evidence of commonalities in the cyclical behaviour of the remaining cities especially those on the eastern and southern coasts of australia

real business cycles and the animal spirits hypothesis abstract we calibrate a quantitative equilibrium macroeconomic model with an aggregate technology that is subject to increasing returns and show that this model may display fluctuations at business cycle frequencies even when there are no shocks to the fundamentals of the economy these fluctuations are due to the self fulfilling beliefs of investors which we call animal spirits we compare the impulse response functions predicted by our model and by two other more standard models with a four variable vector autoregression on u s data our animal spirits economy is the most successful of the three at matching broad features of the dynamic responses in the data journal of economic literature classification numbers e00 e3 e32

testing for convergence between uk regional house prices drake l 1995 testing for convergence between uk regional house prices reg studies 29 357 366 this paper uses the kalman filter time varying parameter estimation technique to test for convergence between uk regional house prices this issue is significant given the historical disparities in regional house price inflation rates and the unprecedented downturn in both uk and most regional house prices in the late 1980s and early 1990s the evidence suggests that there are clear regional differences in the pattern of uk house price movements in particular house prices in the north and scotland show evidence of greater divergence from prices in the rest of the south east region than do the southern and midlands regions drake l 1995 une analyse pour determiner la convergence des prix du marche immobilier regionaux au royaume uni reg studies 29 357 366 cet article se sert de la technique dite kalman filter afin de determiner la convergence des prix du marche immobilier regionaux au royaume uni c

some unpleasant general equilibrium implications of executive incentive compensation contracts abstract we consider a simple real business cycle model in which shareholders hire self interested executives to manage their firm a generic family of compensation contracts similar to those employed in practice is studied when compensation is convex in the firm s dividend an increase in the firm s output results in a more than proportional increase in the managers income incentive contracts of sufficient yet modest convexity are shown to result in an indeterminate general equilibrium one in which business cycles are driven by self fulfilling fluctuations in managers expectations the proposed family of contracts may yield first best outcomes for specific parameter choices

direct evidence of risk aversion as a source of advantageous selection in health insurance abstract using the self stated degree of risk aversion regarding health from the gsoep we find some evidence for risk aversion being a source of advantageous selection risk averse men more often procure supplementary insurance for hospital visits despite needing the additional coverage less

asymmetric information and learning evidence from the automobile insurance market this paper tests the predictions of adverse selection models using data from the automobile insurance market i find that in contrast to what recent research suggests the evidence is consistent w

growth accounting when technical change is embodied in capital this paper revisits the hypothesis that technical change is embodied in capital it extends old results to make them more relevant to the contemporary debates about the adjustment of investment goods for quality change and about the role of embodied technical change as a source of economic growth it is shown that the failure to adjust capital for quality change has the effect of suppressing the quality effects into the conventional total factor productivity residual and it is found that approximately 20 percent of the residual growth of quality adjusted output could be attributed to embodied technical change copyright 1992 by american economic association

health insurance and lifestyles this article contributes to the discussion surrounding the existence of ex ante moral hazard and propitious selection in a voluntary private health insurance scenario moreover it provides an estimation of the determinants of lifestyle choices and of private health insurance demand a multivariate probit is estimated for health insurance demand and lifestyle decisions to take into account the potential endogeneity of these decisions the results indicate that there is evidence of ex ante moral hazard in deciding to do sports and eating healthy snacks hence no propitious selection has been found for these decisions another relevant result shows that there is no individual heterogeneity for the lifestyle choices except for smoking and private health insurance choice evidence from the results also supports the idea that there are nonobservable variables playing a role in the lifestyle decisions these results provide some directions for policymakers such as the promotion of precautionary behaviours a