are health insurance markets competitive to gauge the competitiveness of the group health insurance industry i investigate whether health insurers charge higher premiums ceteris paribus to more profitable firms such direct price discrimination is feasible only in imperfectly competitive settings using a proprietary national database of health plans offered by a sample of large multisite firms from 1998 2005 i find firms with positive profit shocks subsequently face higher premium growth even for the same health plans moreover within a given firm those sites located in concentrated insurance markets experience the greatest premium increases the findings suggest health care insurers are exercising market power in an increasing number of geographic markets

habit formation interdependent preferences and demographic effects in the almost ideal demand system the authors model myopic habit formation interdependence of preferences among consumers and demographic effects as taste shifters in a micro consumer demand model of the almost ideal demand variety the model is estimated for dutch micro data the authors investigate the dynamic properties of the model and find that it behaves very differently from models without interdependence of preferences the implications for micro macro modeling are discussed copyright 1991 by royal economic society

consumer demand and the life cycle allocation of household expenditures the purpose of this paper is to estimate the parameters of household preferences that determine the allocation of goods within the period and over the life cycle using micro data in doing so the authors are able to identify important effects of demographics labor market status and other household characteristics on the intertemporal allocation of expenditure they test the validity of the life cycle model using excess sensitivity tests and find that controlling for demographics and labor market status variables can largely explain the excess sensitivity of consumption to anticipated changes in income

facilitating consumer learning in insurance markets what are the welfare effects we model a monopoly insurance market where consumers can learn their accident risks at a cost c we then ask what are the welfare effects of a policy that reduces c if c is sufficiently small c c marginally reducing c hurts the insurer and weakly benefits the consumer finally a reduction in c that is successful meaning that the consumer gathers information after the reduction but not before it can hurt both parties this article is protected by copyright all rights reserved

smooth it like the joneses estimating peer group effects in intertemporal consumption choice recent theoretical contributions have suggested peer group effects as a potential explanation for several puzzles in macroeconomics but their empirical relevance for intertemporal consumption choice is an open question we derive an extension of the standard life cycle model that allows for consumption externalities in this framework we propose a social multiplier approach to distinguish true externalities from merely correlated effects estimating our model using us panel data we find strong predictable co movement of household consumption within peer groups although much of this co movement reflects correlated effects only there is statistically significant evidence for moderate consumption externalities across several plausible peer group specifications

tax policy and aggregate demand management under catching up with the joneses this paper examines the role for tax policies in productivity shock driven economies with catching up with the joneses utility functions the optimal tax policy is shown to affect the economy countercyclically via procyclical taxes i e cooling down the economy with higher taxes when it is overheating in booms and stimulating the economy with lower taxes in recessions to keep consumption up thus models with catching up with the joneses utility functions call for traditional keynesian demand management policies but for rather unorthodox reasons

intergenerational linkages in consumption behavior consumption is partly a social activity yet most studies of consumer behavior treat households in isolation we investigate familial relationships in consumption patterns using a sample of parents and their children from the panel study of income dynamics we nd a positive and statistically signi cant parent speci c eect on children s consumption even after controlling for the eect of parental income and we nd similar eects for sibling pairs child consumption responds negatively to large post retirement shortfalls in consumption of the parents this behavior holds up even after allowing for the possibility of smaller parent to child transfers made necessary by the parental consumption shortfalls these results suggest that although income is an important source of the intergenerational correlation parental choices and experiences also aect consumption behavior of the children

interdependent preferences an econometric analysis the theoretical model of gaertner 1974 and pollak 1976 for the interdependence of preferences in the linear expenditure system is estimated for a cross section of households the interdependence of consumption of different households has implications for the stochastic structure of the model and for the identifiability of its parameters both aspects are dealt with the empirical results indicate a significant role played by the interdependence of preferences one of its implications is that predictions of the effects of changes in a household s exogenous variables differ according to whether the exogenous variable only changes for this household or for all households jointly c 1997 john wiley sons ltd

habit formation in consumer preferences evidence from panel data this paper tests for the presence of habit formation using household data a simple model of habit formation implies a condition relating the strength of habits to the evolution of consumption over time when the condition is estimated with food consumption data from the panel study on income dynamics the results yield no evidence of habit formation at the annual frequency this finding is robust to a number of changes in the specification it also holds for several proxies for nondurables and services consumption created by combining psid variables with weights estimated from consumer expenditure survey data

general economic conditions and national elections the fact that economic conditions influence voters is a leading commonplace of conversation in election years the question is is this fact in fact a fact despite the overwhelming popularity of the fact it has received neither an explicit theoretical analysis presumably because it is so obvious that economic adversity should create political adversaries nor until recently a satisfactory statistical analysis gerald h kramer has presented a multivariate analysis of congressional elections which would strongly suggest that fluctuations in the rate of unemployment have no appreciable effect upon elections but that fluctuations in per capita real income are influential in the following pages i propose to 1 reaffirm his finding on the electoral unimportance of ordinary fluctuations in unemployment 2 argue that contrary to kramer fluctuations in real income also do not have important electoral effects and 3 present an argument based upon rational voter behavior for the unimportance of general economic conditions in national elections

economic conditions and national elections post sample forecasts of the kramer equations there has long been a division of opinion among economists concerning the effects of economic developments on voting behavior in his well known study kramer 1971a concluded that the fluctuations in economic activity have a systematic influence on u s congressional elections his findings were challenged by various economists including stigler 1973 the purpose of this paper is to extend the analysis of kramer s results by examining the post sample forecast performance of his models as noted by christ 1966 pp 546 49 the acid test of a time series model is its ability to perform well outside the sample period the results discussed below demonstrate that kramer s equations have relatively good post sample predictive ability the findings thus support the view that short term economic fluctuations have important effects on national elections however the results also suggest that economic factors alone are not sufficient to account for all variations of voter behavior

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

who benefits when the government pays more pass through in the medicare advantage program abstract governments contract with private firms to provide a wide range of services while a large body of previous work has estimated the effects of that contracting surprisingly little has investigated how those effects vary with the generosity of the contract in this paper we examine this issue in the medicare advantage ma program through which the federal government contracts with private insurers to coordinate and finance health care for 17 million medicare recipients to do this we exploit a substantial policy induced increase in ma reimbursement in metropolitan areas with a population of 250 000 or more relative to msas below this threshold our results demonstrate that the additional reimbursement leads more private firms to enter this market and to an increase in the share of medicare recipients enrolled in ma plans our findings also reveal that about one eighth of the additional reimbursement is passed through to consumers in the form of better coverage a somewhat larger share accrues to private insurers in the form of higher profits and we find suggestive evidence of a large impact on advertising expenditures our results have implications for a key feature of the affordable care act that will reduce reimbursement to ma plans by 156 billion from 2013 to 2022

life cycle consumption under social interactions abstract in this paper we examine how social interactions affect consumption decisions at various levels of aggregation in a life cycle economy made up of peer groups for this purpose we consider two analytically solvable life cycle models one under certainty equivalent behavior and one under prudence and explicitly allow for three different forms of social interactions in peer groups namely conformism altruism and jealousy we show that whether social interactions have any effects on individuals optimal consumption decisions critically depends on intertemporal rather than static considerations this is true regardless of whether individuals preferences are time separable or exhibit habit formation and whether information within peer groups is homogeneous or disparate it implies that analyzing the effects of social interactions in static rather than intertemporal settings is likely to be misleading we also show that social interactions when coupled with either habit formation or prudence can significantly strengthen the effects of habit formation or prudence in the direction of resolving two well known puzzles in the literature on the permanent income hypothesis namely excess smoothness and excess sensitivity

habits and heterogeneity in demands a panel data analysis we examine demand behaviour for intertemporal dependencies using spanishpanel data we present evidence that there is both state dependence and correlatedheterogeneity in demand behaviour our specific findings are that food outside thehome alcohol and tobacco are habit forming whereas clothing and small durablesexhibit durability we conclude that demand analyses using cross section data thatignore these effects may be seriously biased on the other hand the degree ofintertemporal dependence is not sufficiently strong to make composite consumption significantly habit forming as has been suggested in some recent analyses

an individual health plan exchange which employees would benefit and why on average us workers fortunate enough to be offered health insurance through their place of work are given a small number of choices 80 percent of firms accounting for 37 percent of workers offered only one plan in 2005 although there are merits of limited choice including lower administrative costs for sponsoring employers and better pooling of risk within a given employee population substantial consumer surplus is forgone by preventing employees from selecting plans that best suit their needs in dafny ho and varela 2010 we build a model to quantify this deadweight loss using data on plan offerings and enrollment for 800 large us firms in 139 geographic markets over the period 1998 2006 we estimate a model of consumer preferences for characteristics of health plans we use the parameters of that model to predict employee choices under different hypothetical scenarios of expanded choice assuming employers total outlays for health insurance remain constant and plans are made available to new enrollees at large group rates we quantify those gains for each employee group year we observe for example big box retailer s employees in houston in 2003 and conclude these gains are sizable compared to average premiums we estimate that employees would be willing to forgo ten to 40 percent or more of their employer subsidies for the right to apply those subsidies to the plan of their choosing with the exact magnitude depending on the demand specification as well as the definition of the expanded choice set an individual health plan exchange which employees would benefit and why

price dispersion in mortgage markets using transaction level data on canadian mortgage contracts we document an increase in the average discount negotiated off the posted price and in rate dispersion our aim is to identify the beneficiaries of discounting and to test whether dispersion is caused by price discrimination the standard explanation for dispersion in credit markets is risk based pricing our contracts are guaranteed by government backed insurance so risk cannot be the main factor we find that lenders set prices that reflect consumer bargaining leverage not just costs the presence of dispersion implies a lack of competition but our results show this to be consumer specific

the industrial organization of health care markets the u s health care sector is large and growing health care spending in 2011 amounted to 2 7 trillion and 18 percent of gdp approximately half of health care output is allocated via markets in this paper we analyze the industrial organization literature on health care markets focusing on the impact of competition on price quality and treatment decisions for health care providers and health insurers we conclude with a discussion of research opportunities for industrial organization economists including opportunities created by the u s patient protection and affordable care act

competition leverage how the demand side affects optimal risk adjustment we study optimal risk adjustment in imperfectly competitive health insurance markets when high risk consumers are less likely to switch insurer than low risk consumers insurers then have an incentive to select even if risk adjustment perfectly corrects for cost differences to achieve first best risk adjustment should overcompensate insurers for serving high risk agents second we identify a trade off between efficiency and consumer welfare reducing the difference in risk adjustment subsidies increases consumer welfare by leveraging competition from the elastic low risk market to the less elastic high risk market third mandatory pooling can increase consumer surplus further at the cost of efficiency

price discrimination and bargaining empirical evidence from medical devices many important issues in business to business markets involve price discrimination and negotiated prices situations where theoretical predictions are ambiguous this paper uses new panel data on buyer supplier transfers and a structural model to empirically analyze bargaining and price discrimination in a medical device market while many phenomena that restrict price discrimination are suggested as ways to decrease hospital costs e g mergers group purchasing organizations and transparency i find that 1 non discriminatory pricing actually works against hospitals because competition is more intense under price discrimination and 2 results depend ultimately on a previously unexplored bargaining effect

wages profits and rent sharing the paper suggests a new test for rent sharing in the u s labor market using an unbalanced panel from the manufacturing sector it shows that a rise in a sector s profitability leads after some years to an increase in the long run level of wages in that sector the paper controls for workers characteristics for industry fixed effects and for unionism lester s range of wages is estimated for rent sharing reasons alone at approximately 24 per cent of the mean wage

union contracts and the life cycle permanent income hypothesis this paper isolates households in the psid whose heads can be matched to particular long term union contracts with high confidence the author uses use published information on these contracts to construct a household specific measure of expected wage growth he finds that predictable wage movements are significantly correlated with consumption changes contrary to neoclassical consumption theory the author finds that consumption responds more strongly to predictable income declines than to predictable income increases this asymmetry is inconsistent with liquidity constraints and myopia but is qualitatively consistent with models in which preferences exhibit loss aversion copyright 1995 by american economic association

mergers when prices are negotiated evidence from the hospital industry in recent years many hospitals have merged in part to gain bargaining leverage with managed care organizations mcos we investigate the price impact of hospital mergers by formulating and estimating an equilibrium bargaining model between hospital systems and managed care health insurers over prices for inpatient services we estimate the parameters of the model using claims and discharge data from northern virginia in 2006 inova health system proposed to acquire prince william hospital we nd that this merger would have raised prices signicantly and that the remedy of separate bargaining imposed by the ftc in a separate hospital case would have resulted in a larger price increase

occupational mobility and the distribution of occupational success among young men interpretation of the distribution of occupational success depends crucially on an understanding of the process of mobility if the holders of low paying jobs this year are just as likely as anyone else to hold good jobs next year then the lower tail of the earnings distribution is not a matter of great social concern further if the distribution of success is primarily determined by a random process the prospects for a significant reduction in the inequality of earnings are unfavorable on the other hand high mobility in the short run may conceal systematic stratification of the labor force it may be that the same individuals spend most of their time in the worst jobs if so luck and random events may play a small role in the distribution of well being inequality may be a major issue and the elimination of stratification may hold out the promise of an important reduction in inequality simple tabulation of distributions of success and of mobility among categories of success cannot answer the basic question of the role of stratification in this paper we develop a model and statistical method for studying mobility and relating it to characteristics upon which stratification may be based our study rests on annual interviews conducted from 1966 through 1969 with about 3 000 white males born between 1942 and 1952 1 we find that mobility is closely related to personal characteristics especially intelligence and education men with high iqs and extensive education are more likely to move to high paying jobs and are more likely to remain in them nevertheless random events dominate the distribution of occupational success in the short run our results strongly support the finding of christopher jencks and his collaborators that redistribution of the determinants of earnings would do almost nothing to reduce the observed inequality of annual earnings

search frictions and market power in negotiated price markets we provide a framework for empirical analysis of negotiated price markets using mortgage market data and a search and negotiation model we characterize the welfare impact of search frictions and

imperfect competition in selection markets policies to correct market power and selection can be misguided when these forces coexist we build a model of symmetric imperfect competition in selection markets that parameterizes the degree of market power and selection we use graphical price theoretic reasoning to characterize the interaction between these forces using a calibrated model of health insurance we show that the risk adjustment commonly used to offset adverse selection can reduce coverage and social surplus conversely in a calibrated model of subprime auto lending realistic levels of competition can generate an oversupply of credit implying that greater market power is desirable

risk sharing between and within families this paper uses the panel study of income dynamics to test whether risk sharing is complete between or within american families the tests accommodate a wide variety in the configuration and availability of family data the test results reject inter as well as intra family full risk sharing even assuming that leisure is endogenous or that leisure and consumption are nonseparable

the complementarity between risk adjustment and community rating distorting market outcomes to facilitate redistribution abstract we analyze optimal risk adjustment in competitive health insurance markets when insurers have better information on their customers risk profiles than the sponsor of health insurance in the optimal scheme the sponsor uses reinsurance to screen insurers with bad and good risks in order to lower premiums for enrollees with high expected healthcare costs we then explore the effects of adding a community rating requirement to complement this risk adjustment scheme with community rating insurers have incentives to distort contract generosities to cherry pick low cost consumers however the reduced generosity for low cost types makes screening through reinsurance easier allowing the sponsor to redistribute more when costs for reinsurance are low or the sponsor s bias towards high cost consumers is high community rating dominates risk rating

humps and bumps in lifetime consumption in this article we argue that the life cycle model that allows demographics to affect household preferences and relaxes the assumption of certainty equivalence can generate hump shaped consumption profiles over age that are very similar to those observed in household level data sources and in particular match the differences in shape across different education groups liquidity constraints or myopia are not required to explain the empirical features of observed life cycle patterns

is consumption growth consistent with intertemporal optimization evidence from the consumer expenditure survey in this paper we show that some of the predictions of models of consumer intertemporal optimization are in line with the patterns of nondurable expenditure observed in u s household level data we propose a flexible specification of preferences that allows multiple commodities and yields empirically tractable equations we estimate preference parameters using the only u s micro data set with complete consumption information we show that previous rejections can be explained by the simplifying assumptions made in previous studies we also show that results obtained using good consumption or aggregate data can be misleading

intertemporal preferences and labor supply in this paper the authors examine whether nonseparable preference structures ar e important in characterizing life cycle labor supply using longitud inal data on prime age males from the panel study of income dynamics they estimate a model of life cycle leisure and consumption under un certainty in which intertemporal preferences are allowed to be nonsep arable in leisure the model tests several alternative specifications considered in the literature they investigate the robustness of the ir findings to certain forms of population heterogeneity and types of model misspecification across alternative specifications the autho rs find that the standard assumption of intertemporally separable pre ferences for leisure is not consistent with the data copyright 1988 by the econometric society

unhealthy insurance markets search frictions and the cost and quality of health insurance we analyze the effect of search frictions in the market for commercial health insurance frictions increase insurance premiums enough to transfer 13 2 percent of consumer surplus from fully insured employer groups to insurers approximately 34 4 billion in 1997 and increase insurance turnover by 64 percent for the average pol icy this rent transfer harms consumers and when combined with heightened turnover reduces incentives to invest in future health we also find that a publicly financed insurance option can improve the efficiency of private insurance markets by reducing search fric tion induced distortions in pricing and marketing efforts jel d83 g22 i18 in the united states health insurance for those under age 65 is typically provided through group plans purchased by employers from commercial insurers health insurance is a complex multi attribute service so employers looking to buy insur ance face a difficult shopping problem savvy purchasers must consider which of the many drugs their employees might use are in the insurer s formularies which local physicians are part of the insurer s provider network and what copays fees and deductibles apply to which pharmaceuticals providers and services comparison shopping is made even more difficult by the fact that many aspects of insurance involve commitments to provide services under hard to anticipate contingencies medical underwriting by insurers and the great profusion of insurance products raises administrative costs and increases the complexity of an employer group s

the incidence of mandated maternity benefits i consider the labor market effects of mandates which raise the costs of employing a demographically identifiable group the efficiency of these policies will be largely dependent on the extent to which their costs are shifted to group specific wages i study several state and federal mandates which stipulated that childbirth be covered comprehensively in health insurance plans raising the relative cost of insuring women of childbearing age i find substantial shifting of the costs of these mandates to the wages of the targeted group correspondingly i find little effect on total labor input for that group jel 118 j32 h51 in an era of tight fiscal budget constraints mandating employer provision of workplace benefits to employees is an attractive means for a government to finance its policy agenda consequently in recent years there has been a growth of interest in mandated benefits as a tool of social policy for example the centerpiece of president bill clinton s health care proposal is mandated employer provision of health insurance and more than 20 states have man

paying a premium on your premium consolidation in the us health insurance industry we examine whether and to what extent consolidation in the u s health insurance industry is leading to higher employer sponsored insurance premiums we make use of a proprietary panel dataset of employer sponsored healthplans enrolling over 10 million americans annually between 1998 and 2006 to explore the relationship between premium growth and changes in market concentration we exploit the differential impact of a large national merger of two insurance firms across local markets to estimate the causal effect of concentration on market level premiums we estimate real premiums increased by approximately 7 percentage points in a typical market due to the rise in concentration during our study period we also find evidence that consolidation facilitates the exercise of monopsonistic power vis a vis physicians whose absolute employment and relative earnings decline in its wake

pricing regulation and imperfect competition on the massachusetts health insurance exchange abstract we analyze insurance pricing regulation under imperfect competition on the massachusetts health insurance exchange differential markups lead to price variation apart from cost variation coarse insurer pricing strategies identify consumer demand younger consumers are twice as price sensitive as older consumers older consumers thus face higher markups over costs modified community rating links prices for consumers differing in both costs and preferences and changes the marginal consumer firms face stricter regulations transfer resources from low cost to high cost consumers reduce firm profits and increase overall consumer surplus

does contracting out increase the efficiency of government programs evidence from medicaid hmos state governments contract with health maintenance organizations hmos to coordinate medical care for nearly 20 million medicaid recipients identifying the causal effect of hmo enrollment on government spending and health care quality is difficult if as is often the case recipients have the option to enroll in a plan to estimate the average effect of hmo enrollment this paper exploits county level mandates introduced during the last several years in the state of california that required most medicaid recipients to enroll in a managed care plan the empirical results demonstrate that the resulting switch from fee for service to managed care was associated with a substantial increase in government spending but no corresponding improvement in infant health outcomes the findings cast doubt on the hypothesis that hmo contracting has reduced the strain on government budgets

the life cycle model of consumption and saving a central implication of life cycle models is that agents smooth consumption we review the empirical evidence on smoothing at frequencies from within the year up to across a lifetime we find that life cycle models particular those which incorporate realistic features of markets and goods have more empirical successes than failures we also show that some apparent deviations from theoretical predictions imply very small welfare losses for agents finally we emphasize that the coherence of life cycle models imposes an important discipline when incorporating new features into models

full insurance in the presence of aggregate uncertainty this paper tests implications of full consumption insurance the object is to determine how much mileage can be obtained from a model with complete markets with such features as private information or liquidity constraints omitted the implication exploited is that individual consumption responds to aggregate risk but not to idiosyncratic risk the test involves regressing the change in household consumption onto the change in aggregate consumption and other right hand side variables such as the change in household income and change in employment status all variables other than the change in aggregate consumption are predicted to be insignificant in explaining the change in household consumption with observations on consumption and income for 10 695 households from the consumer expenditure survey the results are mixed the results for one specification exponential utility are mostly consistent with full consumption insurance the results for the other specification power utility are not

perfect competition in markets with adverse selection this paper proposes a perfectly competitive model of a market with adverse selection prices are determined by zero profit conditions and the set of traded contracts is determined by free entry crucially for applications contract characteristics are endogenously determined consumers may have multiple dimensions of private information and an equilibrium always exists equilibrium corresponds to the limit of a differentiated products bertrand game we apply the model to establish theoretical results on the equilibrium effects of mandates mandates can increase efficiency but have unintended consequences with adverse selection an insurance mandate reduces the price of low coverage policies which necessarily has indirect effects such as increasing adverse selection on the intensive margin and causing some consumers to purchase less coverage

insurer provider networks in the medical care market i use data on the hospital networks offered by managed care health insurers to estimate the expected division of profits between insurers and providers i include a simple profit maximization framework and an additional effect hospitals that can secure demand without contracting with all insurers e g those most attractive to consumers and those that are capacity constrained may demand high prices that some insurers refuse to pay hospital mergers may also affect price bargaining i estimate that all three types of hospitals capture higher markups than other providers these results provide information on the hospital investment incentives generated by bargaining

household choices in equilibrium this paper is an empirical investigation of equilibrium restrictions on household consumption and male labor supply it exploits a simple factor structure rationalized by two assumptions that household allocations are pareto optimal and that the labor market is competitive the paper estimates household preferences and tests how well this parsimonious factor structure represents panel data on married couples and time series data on asset returns most of the estimates are roughly comparable to those found in previous work no evidence against the simple factor representation is found and the intertemporal capital asset pricing model is not rejected copyright 1990 by the econometric society

a simple test of consumption insurance are consumers effectively insured against idiosyncratic shocks to income or wealth either by formal institutions such as charities private insurance and government programs or by informal mechanisms such as gifts and loans from relatives friends and neighbors under full insurance consumption growth should be cross sectionally independent of idiosyncratic variables that are exogenous to consumers this proposition is tested by cross sectional regressions of consumption growth on a variety of exogenous variables full insurance is rejected for long illness and involuntary job loss but not for spells of unemployment loss of work due to strike and an involuntary move

social interactions and habit formation in a model of female labour supply this paper investigates the influence of habit formation and preference interdependence on labour supply behaviour of married females a novelty of the paper is that we incorporate direct survey information on reference groups of individuals in a neoclassical labour supply model for that purpose we first estimate a latent variables model relating the direct information to the true but unobserved reference groups one of the most interesting features of the model is that the presence of young children becomes an insignificant factor in the hours equation while it remains a significant factor in the participation decision in addition the labour supply curve is much flatter in a model with habit formation and preference interdependence than in a model without it both habit formation and preference interdependence contribute significantly to the explanation of female labour supply 1998 elsevier science s a all rights reserved

identification of endogenous social effects the reflection problem this paper examines the reflection problem that arises when a researcher observing the distribution of behaviour in a population tries to infer whether the average behaviour in some group influences the behaviour of the individuals that comprise the group it is found that inference is not possible unless the researcher has prior information specifying the compisition of reference groups if this information is available the prospects for inference depend critically on the population relationship between the variables defining reference groups and those directly affecting outcomes inference is difficult to implossible if these variables are functionally dependent or are statistically independent the prospects are better if the variables defining reference groups and those directly affecting outcomes are moderately related in the population

the impact of a public option in the u s health insurance market we develop a game theoretical framework to examine the implications of the introduction of a nonprofit public option in the u s health insurance market in this model heterogeneous consumers have to choose between two competing insurance plans one plan is offered by a profit maximizing private insurer the other by social welfare maximizing public option in equilibrium the distinct objectives of the two insurers induce adverse selection in consumer choice the public option covers the less healthy consumers yielding the more profitable segment of market to the private insurer however our empirical results suggest that both insurers will capture significant parts of the health insurance market jel i11 l10 l21 l32

how does risk selection respond to risk adjustment new evidence from the medicare advantage program to combat adverse selection governments increasingly base payments to health plans and providers on enrollees scores from risk adjustment formulae in 2004 medicare began to risk adjust capitation payments to private medicare advantage ma plans to reduce selection driven overpayments but because the variance of medical costs increases with the predicted mean incentivizing enrollment of individuals with higher scores can increase the scope for enrolling overpriced individuals with costs significantly below the formula s prediction indeed after risk adjustment ma plans enrolled individuals with higher scores but lower costs conditional on their score we find no evidence that overpayments were on net reduced

insurer pricing and consumer welfare evidence from medigap this article examines the welfare impact of imperfect competition in the medicare supplement insurance medigap market two firms control nearly three fourths of the medigap market and premiums exceed claims by over 25 i find that a low price elasticity and consumers brand preferences lead firms to engage in substantial marketing and price above cost therefore the strategic behavior of insurers facing relatively inelastic demand is critical in explaining poor market performance i also find that insurers do not capture all of the rents in this market rents also accrue to actors who perform marketing functions including agents and brokers

the effect of medicare part d on pharmaceutical prices and utilization prescription drug expenditures represent the most rapidly growing component of health care spending increasing from 5 percent of health care spending in 1980 to more than 10 percent by 2005 centers for medicare and medicaid services cms 2007a further almost 60 percent of all prescriptions in the united states are filled for beneficiaries of medicare medicaid and other government programs rapid innovation in new pharmaceuticals has contributed substantially to quality of life and longevity in the us frank lichtenberg 1996 these facts combined indicate that government procurement schemes are critical both in determining government expenditure on pharmaceuticals and in stimulating innovation of new treatments in this paper we show that the institutions and mechanisms used by the government to pur chase prescription drugs can strongly affect market outcomes by institutions we have in mind large buyer groups structured incentives for patients to consume certain products and the devel opment and use of formularies a formulary is a mechanism that allows a buyer to identify a therapeutically similar treatment as a viable substitute for a patented treatment and to create price competition due to the ability to substitute away from the more expensive product when bargaining with the seller of a patented product the ability to shift demand to a substitute drug is a powerful negotiating tool our paper provides evidence for what we consider a surprising outcome in the case of the new prescription drug program for medicare enrollees moving consumers from cash paying status to membership in an insured group lowers optimal prices for branded prescription drugs below what they otherwise would be this is surprising because the standard effect of insurance is to create inelastic demand and therefore elicit higher prices from a seller with market power duggan and scott morton 2006 however the insurers that we study bundle insurance with a formulary and other mechanisms to create elastic demand an individual consumer typically does not know which drugs are acceptable therapeutic substitutes the consumer s physician typi cally has poor knowledge of prices especially negotiated prices and any one consumer is too small a share of demand to negotiate with a pharmaceutical company a prescription drug plan can potentially surmount all three hurdles our evidence leads us to conclude that the formulary and other mechanisms perform the spe cial role of allowing buyers to move market share among drugs with patent protection thereby raising cross price elasticities and lowering purchase prices or reducing price increases for branded drugs this result contrasts with the common intuition that an uninsured consumer

differentiation and competition in hmo markets this paper examines how differentiation among health maintenance organizations hmos affects local market competition most markets for hmos appear sufficiently unconcentrated however differences among hmos may make competition less intense than the number of competitors would suggest to investigate this possibility we distinguish hmos that serve only local markets from those that operate regional or national networks we analyze how hmos of one type affect the profitability of the other using an equilibrium model of entry and product choice while the two types of hmos have strong competitive effects within segments the competitive effect of differentiated firms is negligible

how do health insurer market concentration and bargaining power with hospitals affect health insurance premiums the us health insurance industry is highly concentrated and health insurance premiums are high and rising rapidly policymakers have focused on the possible link between the two leading to aca provisions to increase insurer competition however while market power may enable insurers to include higher profit margins in their premiums it may also result in stronger bargaining leverage with hospitals to negotiate lower payment rates to partially offset these higher premiums we empirically examine the relationship between employer sponsored fully insured health insurance premiums and the level of concentration in local insurer and hospital markets using the nationally representative 2006 2011 kff hret employer health benefits survey we exploit a unique feature of employer sponsored insurance in which self insured employers purchase only administrative services from managed care organizations to disentangle these different effects on insurer concentration by constructing one concentration measure representing fully insured plans transactions with employers and the other concentration measure representing insurers bargaining with hospitals as expected we find that premiums are indeed higher for plans sold in markets with higher levels of concentration relevant to insurer transactions with employers lower for plans in markets with higher levels of insurer concentration relevant to insurer bargaining with hospitals and higher for plans in markets with higher levels of hospital market concentration

campaign finances and political platforms the economics of political controversy one implication of the widely used median voter model is that candidates have little to gain by disagreement apart from some epsilon of controversy necessary to demonstrate which candidate is closer to the median voter position in the policy dimension in question votes are maximized by taking essentially identical position this is true at the nash median voter equilibrium and is true away from equilibrium as a consequence two candidate competition within one dimensional policy domain is expected to generate considerable agreement about appropriate policy we do in fact observe that in many elections candidate positions converge to very similar positions on matters of broad concern it is largely this convergence that gives the median voter model its considerable credence in spite of the fragility of the underlying theory on the other hand the convergence is rarely as complete as might have been expected and there are elections where candidates take substantively different positions this paper explores the extent to which the campaign contributions of politically active groups may draw candidates away from the median voter position as candidate seek funds to run effective election campaigns candidates gener

screening and adverse selection in frictional markets we develop a tractable framework for analyzing adverse selection economies with imperfect competition in our environment uninformed buyers offer a general menu of screening contracts to privately informed sellers some sellers receive offers from multiple buyers while others receive offers from only one buyer as in burdett and judd 1983 this specification allows us to smoothly vary the degree of competition nesting monopsony and perfect competition a la rothschild and stiglitz 1976 as special cases we show that the unique symmetric mixed strategy equilibrium exhibits a strict rank preserving property in that different types of sellers have an identical ranking over the various menus offered in equilibrium these menus can be all separating all pooling or a mixture of both depending on the distribution of types and the degree of competition in the market this calls into question the practice of using the incidence of separating contracts as evidence of adverse selection without controlling for market structure we examine the relationship between exante welfare and the degree of competition and show that in some cases an interior level of frictions maximizes welfare while in other cases competition is unambiguously bad for welfare finally we study the effects of various policy interventions such as disclosure and non discrimination requirements and show that our model generates new and perhaps counter intuitive insights

home is where the equity is mortgage refinancing and household consumption applying a permanent income model with exogenous liquidity constraints and mortgage behavior household refinancing when mortgage interest rates are historically high and rising a persistent empirical puzzle is explained using data from the panel study of income dynamics households experiencing an unemployment shock and having limited initial liquid assets to draw upon are shown to have been 25 more likely to refinance 1991 94 on average such liquidity constrained households converted over two thirds of every dollar of equity they removed into current consumption as mortgage rates plummeted 1991 94 producing an estimated expenditure stimulus of at least 28 billion

adverse selection and an individual mandate when theory meets practice we develop a model of selection that incorporates a key element of recent health reforms an individual mandate using data from massachusetts we estimate the parameters of the model in the individual market for health insurance we find that premiums and average costs decreased significantly in response to the individual mandate we find an annual welfare gain of 4 1 per person or 51 1 million annually in massachusetts as a result of the reduction in adverse selection we also find smaller post reform markups