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

market behavior in the presence of costly imperfect information experimental evidence abstract we investigate the effects of imperfect private information on prices in an experimental asset market we compare bayesian predictions with market prices examine information dissemination and consider the value of imperfect information we find some evidence that market prices are consistent with bayes rule we also find that non bayesian prices are more likely to arise as the degree of uncertainty associated with private information increases imperfect information is disseminated in our experimental markets and traders perceive that imperfect information has value

intra firm bargaining under non binding contracts we present a new methodology for studying the problem of intra firm bargaining based on the notion that contracts cannot commit the firm and its agents to wages and employment we develop and analyse a general non cooperative multilateral bargaining framework between the firm and its employees and consider outcomes which are immune to renegotiations by any party equilibrium firm profits are characterizable as both a weighted average of a neo classical non bargaining firm s profits and a generalization of shapley value for a corresponding cooperative game furthermore the resulting payoffs induce economically significant distortions in the firm s input and organizational design decisions

earnings skewness and analyst forecast bias abstract we argue that if analysts objective is to provide the most accurate forecast by minimizing the mean absolute forecast error then the optimal forecast is the median instead of the mean earnings forecast bias is observed when the median is different from the mean in a skewed earnings distribution thus part of the observed analyst forecast bias could be a result of analysts efforts to improve forecast accuracy when the earnings distribution is skewed we find that earnings skewness is significantly related to analyst forecast bias we also provide evidence that the market adjusts for part of the skewness induced bias

introduction to the stability of rational expectations equilibrium abstract this paper surveys the literature which examines the stability of the expectations that agents are assumed to have in a rational expectations equilibrium ree this issue is more complex than the usual statistical estimation problem because the relationship between observable variables and payoff relevant variables is endogenous one approach taken in the literature yields convergence to a ree but requires agents to have extensive knowledge about the structure and dynamics of the model that prevails while they learn a second approach does not assume that agents have correctly specified likelihood functions and finds that ree may not be stable

equilibrium price formation and the value of private information an economy is analyzed in which agents first choose whether to acquire costly information about the return to a risky asset and then choose demand functions that determine the allocation of assets it is a well known paradox that if agents are price takers and prices are fully revealing then an equilibrium with costly information acquisition does not exist it is shown that if the price formation process is modeled explicitly and agnets are not price takers then it is possible to have an equilibrium with fully revealing prices and costly information acquisition article published by oxford university press on behalf of the society for financial studies in its journal the review of financial studies

the multiple unit double auction the note outlines institutional features of an open outcry market that permit multiple unit or block trades the purpose of the note is to introduce the process as a tool to be used in economics experiments the detailed rules governing the multiple unit double auction muda are stated for the case where offers are tendered by voice as opposed to through a computer the results of markets that use the rules are reported as a demonstration that convergence to equilibrium price traditionally observed in experimental markets remains with the use of the muda process

what affects the market s ability to adjust for optimistic forecast bias evidence from experimental asset markets abstract this study uses experimental asset markets to investigate the effects of experience and common knowledge on a market s ability to adjust for optimistic forecast bias as a baseline we find that period end prices reflect unbiased forecasts in markets with private information and inexperienced traders with low bias forecasts traders need experience before price adjusts for the bias with high bias forecasts traders need experience and public forecast releases before price adjusts for the bias overall our findings provide insight into identifying conditions that are critical for the full revelation of biased imperfect forecasts and provide direction for future theoretical work

does privatisation of vocational rehabilitation improve labour market opportunities evidence from a field experiment in sweden this paper analyses if privatisation of vocational rehabilitation can improve labour market opportunities for individuals on long term sickness absence we use a field experiment performed by the p

market for information experimental evidence predictions of the noisy rational expectations equilibrium ree model are found to be relatively accurate for both asset and information markets in the laboratory when information about an asset s uncertain dividend is sold to a fixed number of highest bidders prices allocations efficiency and distribution of profit predictions of the full revelation ree model in the asset market dominate the predictions of the walrasian model demand for information shifts to the left and its price declines close to zero when the price of information is fixed at a relatively high level the number of informed agents and the informativeness of the asset market tends to adjust to permit the informed agents to recover their investment in information

mexico s balance of payments crisis a chronicle of a death foretold this paper claims that the roots of mexico s balance of payments crisis are found in the prevailing high degree of capital mobility and financial globalization under these circumstances shifts in foreign capital flows and anticipation of a banking system bailout may produce large imbalances between stocks of financial assets and foreign reserves threatening the sustainability of currency pegs econometric analysis suggests that half of mexico s reserve losses could be accounted for by these phenomena large financial imbalances are also fertile ground for self fulfilling prophesy crises which lead devaluations to produce deep recessions these difficulties can be partly remedied by appropriate policies

experience and confidence in an internet based asset market experiment the experience effect in asset markets is one that was thought to be settled as subjects gained experience with the interface and each other they typically exhibit fewer instances of mispricing and at lower magnitudes but questions regarding trading experience are not easy to address in the lab with the typical subject pool since the kind of experience one can typically generate in the lab is experience with the experimental environment itself not with external environments however in virtual worlds asset markets are highly evolved providing a subject pool with skilled and experienced traders that can be accessed via the internet this study compares experimental asset markets with participants recruited from virtual world trading groups to experimental markets with participants recruited from the virtual world at large i further examine trader performance and trading behavior within markets the findings indicate that asset markets with virtual world participants recruited from trading groups are more prone to exhibit bubbles than are markets with virtual world participants recruited at large within condition experienced traders are less likely to follow fundamentals and more likely to engage in strategies that result in loss of earnings excess confidence is rejected as an explanation for this pattern as confidence is found to be related to higher earnings and fundamental value trading strategies

economics of public good provision auditing outsourcing and bribery this study investigates a government s contracting decision to audit or outsource the provision of a public good given a potential hidden bribe and information asymmetries the key findings are the following first the bribe and price of the public good are increasing in the corruptibility of the department second the bribe is decreasing in the firm s bargaining power third a bribery equilibrium exists when the department s corruptibility is sufficiently high given the firm s bargaining power a bribe involves extortion or a compensatory payment depending on the department s corruptibility only a compensatory bribe affects the department s contracting decision ce memoire examine une decision contractuelle d un gouvernement de produire un bien public lui meme et de faire une verification ou d aller en sous traitance pour la fourniture d un bien public compte tenu de la possibilite de pot de vin cache et d asymetries informationnelles les principaux resultats s enoncent comme suit d abord le pot de vin et le prix du bien public s accroissent avec le degre de corruptibilite du ministere ensuite la taille du pot de vin decline a proportion que le pouvoir de marchandage de la firme s accroit enfin un equilibre de corruption existe quand la corruptibilite du ministere est suffisamment elevee compte tenu du pouvoir de marchandage de la firme un pot de vin implique une extorsion ou un paiement compensatoire selon la corruptibilite du ministere seul un paiement compensatoire affecte la decision contractuelle du ministere

the changing role of government in financing health care an international perspective this paper explores the changing role of government involvement in health care financing policy outside the united states it provides a review of the economics literature in this area to elucidate the implications of recent policy changes on efficiency costs and quality our review reveals that there has been some convergence in policies adopted across countries to improve financing incentives and encourage efficient use of health services in the case of risk pooling all countries with competing pools experience similar difficulties with selection and are adopting more sophisticated forms of risk adjustment in the case of hospital competition the key drivers of success appear to be what is competed on and measurable rather than whether the system is public or private in the case of both the success of performance related pay for providers and issues resulting from wait times evidence differs within and across jurisdictions however the evidence does suggest that some governments have effectively reduced wait times when they have chosen explicitly to focus on achieving this goal many countries are exploring new ways of generating revenues for health care to enable them to cope with significant cost growth but there is little evidence to suggest that collection mechanisms alone are effective in managing the cost or quality of care jel h51 i11 i18

market behavior in the presence of divergent and imperfect private information experimental evidence from canada china and the united states abstract we conduct 27 asset markets to examine market behavior when traders have divergent and imperfect information each market consists of well informed wi and less informed li agents nine markets each are conducted in canada china and the us we find that wi agents private information is partially but not fully reflected in prices we also document cross country differences in the degree to which private information is reflected in prices lastly we find that wi agents are able to exploit their informational advantage and outperform li agents this result holds across countries

domestic and external factors in the determination of the real interest rate the case of uruguay the high level of the real interest rates in the 1980s is not a phenomenon limited to small countries the united states and other industrial countries in europe have been confronted with a similar experience although numerous studies have aimed to explain the level of real interest rates within the framework of developed countries there is a lack of theoretical and empirical work about the determination of real interest rates in small open developing countries and about the process of transmitting variations in the real interest rates across countries

hospital ownership and public medical spending the hospital market is served by firms that are private for profit private not for profit and government owned and operated i use a plausibly exogenous change in hospital financing that was intended to improve medical care for the poor to test three theories of organizational behavior i find that the critical difference between the three types of hospitals is caused by the soft budget constraint of government owned institutions the decision makers in private not for profit hospitals are just as responsive to financial incentives and are no more altruistic than their counterparts in profit maximizing facilities my final set of results suggests that the significant increase in public medical spending examined in this paper has not improved health outcomes for the indigent i introduction the hospital market is served by firms that are private for profit private not for profit and publicly owned and operated in this paper i examine how a hospital s type of ownership influences its response to profitable opportunities that are created by changes in government policy the policy change that i exploit was designed to improve the quality of medical care for lowincome individuals by significantly increasing hospitals financial incentives to treat them this program also substantially increased the revenues of those hospitals that had been serving a disproportionate share of the indigent i use this plausibly exogenous change in government policy to test three different theories of organizational behavior and then to assess the impact of hospital behavioral responses on health outcomes the response of organizations to changes in government policy will have an important impact on the consequences of these policies this is likely to be especially true in the medical sector in which the federal state and local governments contract directly

reimbursing health plans and health providers efficiency in production versus selection the tradeoff between an insurer s or medical provider s incentives to select good risks and to produce efficiently is governed by the supply price analog to the demand price tradeoff between moral hazard and risk aversion under a variety of models the optimum supply price is a mixture of capitation and fee for service payments empirical literature shows that pure capitation payment leaves strong incentives for selection that are acted upon the presence of contracting costs in a rothschild stiglitz model means a limited pooling equilibrium can exist and that poor risks will not be at their preferred outcome

price formation in double auction markets abstract this paper reports 14 laboratory experiments that examine existing theories of the price formation process in the continuous double auction the experiments feature random values and costs and therefore a new price formation observation each period we find that efficiency is high and rises with experience in this environment we also find that trades with greater exchange surplus tend to occur earlier in the period that increased trader experience reduces an anomalous intertemporal arbitrage opportunity observed previously and that only when traders are very experienced does exchange surplus accrue disproportionately to the side of the market with a smaller number of traders

a dynamic model of expectations equilibrium abstract this paper describes a dynamic information adjustment process which achieves rational expectations equilibria for stochastic exchange environments an informational temporary equilibrium is an exchange equilibrium in which agents expectations are conditioned on their initial information and market data generated in previous informational temporary equilibria an equilibrium is a temporary equilibrium which reveals no further information this process leads to an equilibrium even when the data observed by agents is insufficient to permit the existence of an expectations equilibrium

an experiment on the efficiency of bilateral exchange under incomplete markets abstract we test in a controlled laboratory environment whether traders in a bilateral exchange internalize the impact of their actions on market prices better than in a large market in this model traders choose asset holdings constrained by a technology frontier next each trader experiences a random shock which makes only one type of asset profitable in a general equilibrium environment with incomplete markets this leads to pecuniary externalities because traders increase scarce asset holdings beyond what is socially optimal this behavior is especially exacerbated in large experimental markets as traders fail to internalize the impact of their actions on prices we find that when markets are incomplete a bilateral exchange can slightly mitigate the extent of pecuniary externalities and weakly increase welfare

outsourcing education experimental evidence from liberia in 2016 the liberian government delegated management of 93 randomly selected public schools to private providers providers received us 50 per pupil on top of us 50 per pupil annual expenditure in control schools after one academic year students in outsourced schools scored 0 18 higher in english and mathematics we do not find heterogeneity in learning gains or enrollment by student characteristics but there is significant heterogeneity across providers while outsourcing appears to be a cost effective way to use new resources to improve test scores some providers engaged in unforeseen and potentially harmful behavior complicating any assessment of welfare gains

why so much error in analysts earnings forecasts wall street analysts tend to be too optimistic about the earnings prospects of companies they follow the average consensus 12 month eps growth forecast is 17 7 percent which is more than twice the actual growth rate in aggregate forecasts are 11 2 percent above actual earnings at the start of a year and are revised downward continuously in the course of the year for the full study period reported here the percentage of 12 month earnings estimates revised downward exceeded the percentage revised upward on average by 4 4 percent every month since 1993 however the quality of analyst forecasts seems to have improved this article provides an intuitive explanation of the change and suggests ways in which analysts can use the explanation to improve portfolio performance

resurrecting the weak credibility hypothesis in models of exchange rate based stabilization abstract we analyze how weak credibility affects the volatility of consumption spending in a model of exchange rate based stabilization that allows for both durable and nondurable goods the inclusion of durables greatly improves the explanatory power of the weak credibility hypothesis the hypothesis can account for the main qualitative properties of the boom bust cycle provided the elasticity of durables expenditure with respect to tobin s q is greater than the intertemporal elasticity of substitution moreover the quantitative effects are very large in numerical simulations based on conservative assumptions about the expenditure share of durables 20 and wealth effects none aggregate consumption increases 17 22 and the real exchange rate appreciates 24 26 when the crawl decreases from 100 to zero for 3 years in variants of the model that incorporate supply effects the consumption boom is equally strong but appreciation of the real exchange rate rises to 30 40

privatizing public services and strategic behavior the impact of incentives to reduce workers compensation claim duration abstract during the 1990s the state of ohio contracted out workers compensation wc case management incorporating a large bonus payment intended to reward reduced claim duration the bonus is essentially a decreasing function of average days away from work excluding claims longer than 15 months in response duration is predicted to decrease for claims with moderate injuries and increase for some severe claims so that claimants will miss more than 15 months of work and be excluded from the calculation i show that contractors increased duration for severe claims but find no evidence that contractors successfully reduced duration for moderate claims however contractors received large bonus payments this is likely because the financial reward to merely excluding a small share of severe claims from the calculation of the bonus payment is large enough to enable tcms to receive the full bonus these contractor responses are inconsistent with state intentions suggesting public entities should anticipate strategic behavior when crafting performance based incentives

optimal health insurance for multiple goods and time periods we examine the efficiency based arguments for second best optimal health insurance with multiple treatment goods and multiple time periods correlated shocks across health care goods and over time interact with complementarity and substitutability to affect optimal cost sharing health care goods that are substitutes or have positively correlated demand shocks should have lower optimal patient cost sharing positive serial correlations of demand shocks and uncompensated losses that are positively correlated with covered health services also reduce optimal cost sharing our results rationalize covering pharmaceuticals and outpatient spending more fully than is implied by static one good or one period models

stock prices and the dissemination of analysts recommendation this article investigates alternative explanations for the significant stock price reaction to analysts information reported in the heard on the street column of the wall street journal the observed market reaction persists after eliminating firms with confounding releases and firms for which analysts reports are issued immediately prior to publication the evidence indicates that the column is not usually a secondary dissemination first stock prices adjust prior to publication when recommendations are reported on a single firm second analysts have incentives to release information to the column before disseminating it to their clients overall the evidence suggests that the heard on the street column gathers information forms a consensus and provides it to investors copyright 1991 by university of chicago press

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

efficiency of experimental security markets with insider information an application of rational expectations models the study reports on the ability of competing models of market information integration and dissemination to explain the behavior of simple laboratory markets for a one priced security returns to the security depended upon a randomly drawn state of nature some agents insiders whose identity was unknown to other agents knew the state before the markets opened with replication of market conditions the predictions of a fully revealing rational expectations model are relatively accurate prices adjusted immediately to near rational expectations prices profits of insiders were virtually indistinguishable from non insiders and efficiency levels converged to near 100 percent

medicaid managed care effects on children s medicaid coverage and utilization abstract we use data from the national health interview surveys nhis to measure the effects of the growth of medicaid managed care on children we examine both the probability that individual children were medicaid covered and their utilization of care we find that managed care penetration has significant effects on the composition of the medicaid caseload young children are less likely to be covered while poor school age children are more likely to be covered when we examine coverage by race we find that black children are less likely to be covered where medicaid managed care organizations mmcos are more prevalent these lower medicaid enrollment rates are linked to increases in the numbers of young children who go without any doctor visits in a year these results suggest that it is important to examine the potential effects of changes in medicaid on selection into the medicaid program rather than focusing exclusively on the effects of managed care on those who are enrolled in addition among those enrolled in medicaid higher managed care penetration is associated with an increase in the number of black children with chronic conditions who go without doctor visits but with decreases in the number of hispanic children and poor teens who go without care

price conveyed information versus observed insider behavior a note on rational expectations convergence in a recent paper on behavior in experimental securities markets plott and sunder 1982 concluded that the rational expectations re model was superior to the traditional prior information pl model in predicting equilibrium prices and holdings in particular given a market with one commodity three possible states of the world and three groups of trader types each with differing valuations on the commodity per state initially uninformed traders were able to infer the underlying state from the current market price and act accordingly in a related paper friedman harrison and salmon 1984 observed that given the existence of a futures market the re model outperformed the pi model in multiperiod single commodity markets as well one source of potential misinterpretation however comes from the fact that although one half of the traders of each type were informed of the true state at the beginning of each period in plott and sunder 1982 and one third of the traders of each type in friedman harrison and salmon 1984 the same traders were informed in almost every period in a more recent paper plott and sunder 1983 constructed markets where all traders received partial information i e given possible states x y and z a trader s private information would be either not x or not y if the state were z yet the combinations of traders receiving a certain message in any period were determined randomly

how do hospitals respond to managed care evidence from at risk newborns abstract medicaid has increasingly transitioned from a government run fee for service system ffs to a managed care system mmc administered by private insurers to examine the effect of mmc i exploit an arbitrary determinant of mmc enrollment in new york state infants weighing less than 1200 g were excluded from mmc and were instead served through ffs i find evidence that mmc reduces hospital costs at birth which is driven by infants born in new york city the hospital cost reductions arise from shortening the lengths of stay and encouraging inter hospital transfers these results are consistent with health plans influencing hospitals to reduce the intensity of treatment and steering patients away from high cost hospitals

effects of contracting out employment services evidence from a randomized experiment in many countries welfare services that traditionally have been provided by the public sector are being contracted out to private providers but are private contractors better at providing these services we use a randomized experiment to empirically assess the effectiveness of contracting out employment services to private placement agencies our results show that unemployed at private placement agencies have a closer interaction with their case worker than unemployed at the public employment service pes e g they receive more assistance in improving their job search technology we do not find any overall difference in the chances of finding employment between private placement agencies and the pes but this hides important heterogeneities across different types of unemployed in particular private providers are better at providing employment services to immigrants whereas they may be worse for adolescents any effects tend to fade away over time

why do hmos spend less patient selection physician price sensitivity and prices abstract cost control incentives have become an important part of the health insurance landscape in the united states these incentives are the strongest in capitated managed care organizations especially hmos because such organizations are paid a fixed amount regardless of the spending they generate using a sample of insurance claims from about 500 plans i find that in hmos spending on anti cholesterol drugs is 19 lower than in other insurance plans this spending difference could reflect the strong cost control incentives generated by capitation but it could also reflect the selection of healthy price sensitive patients into hmos or it could simply reflect lower prices to understand the difference i estimate a model of physician prescribing and patient refill decisions patients in hmos are nearly twice as sensitive to copays as are other patients consistent with selection of healthy patients into hmos even after adjusting for this selection however hmo physicians remain highly sensitive to drug procurement costs this high sensitivity explains about a 20 of the spending difference combined with lower prices it explains about 25 55 of the difference i find no evidence that these spending reductions result in fewer patient refills or the prescribing of less effective statins

policy fundamentals interest rates differential and expected devaluation in the presence of an active crawling peg system abstract one of the most interesting theoretical issues that comes up from the analysis of the tablita period in the southern cone economies argentina chile and uruguay is the interpretation of why interest rates on domestic currency loans were much higher than the rate on foreign currency loans adjusted for devaluation of the domestic currency even though the rate of devaluation was set by the monetary authorities six months ahead and published in a little table tablita this was particularly puzzling in the case of uruguay which had practically perfect capital mobility we show that the reason rational economic agents were willing to pay high domestic interest rates rather than borrowing in foreign currency was that they realized that policy fundamentals were inconsistent with the sustainability of the exchange rate policy using data for uruguay we show that a second systematic component of expectations of devaluation is what we call the policy risk factor and modeled as a function of the fiscal and monetary variables jel 41 31

conflict of interest and the credibility of underwriter analyst recommendations brokerage analysts frequently comment on and sometimes recommend companies that their firms have recently taken public we show that stocks that underwriter analysts recommend perform more poorly than buy recommendations by unaffiliated brokers prior to at the time of and subsequent to the recommendation date we conclude that the recommendations by underwriter analysts show significant evidence of bias we show also that the market does not recognize the full extent of this bias the results suggest a potential conflict of interest inherent in the different functions that investment bankers perform

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

deja vu all over again the mexican crisis and the stabilization of uruguay in the 1970s abstract comparing the 1978 1982 uruguayan stabilization with the 1990 1994 mexican experience reveals that exchange rate based stabilization tends to increase the economy s vulnerability to unexpected shocks an exchange rate rule with full capital mobility can only succeed if compatible financial policies are strictly adhered to even when severe negative shocks take place and if reliance on persistent capital inflows is not essential this requires monetary restraint even under serious recessionary conditions and tight fiscal policies to moderate interest rates the epilogues of both experiences demonstrate that abandoning the exchange rate rule in the wake of a shock even if inevitable makes future stabilization more difficult

information dissemination and the distribution of wealth evidence from experimental asset markets abstract we conduct 24 experimental asset markets to investigate the effects of differentially informed and experienced agents on information dissemination and the distribution of wealth in our markets private information is incomplete in that it reduces but does not eliminate state uncertainty private information is not fully disseminated even in markets with experienced traders informed agents exploit their informational advantage and earn greater profit than uninformed agents but only in markets with inexperienced traders lastly uninformed agents earn greater profit when some agents are informed but only in markets with experienced traders overall uninformed agents benefit from design specific trading experience

the market value of information some experimental results the authors examine the price and allocation of purchased information and of the underlying asset in eight double auction asset market experiments observed outcomes support fully revealing rational expectations in simple environments in which uninformed traders can easily infer the private information of informed traders but support nonrevealing rational expectations in more complex environments the private value of information is positive in the more complex noisy environments but competition forces the information price to its nash equilibrium value and the net gain by purchasers is approximately zero copyright 1992 by university of chicago press

risk selection and heterogeneous preferences in health insurance markets with a public option conventional wisdom suggests that if private health insurance plans compete alongside a public option they may endanger the latter s financial stability by cream skimming good risks this paper argues that two factors may contribute to the extent of cream skimming i degree of horizontal differentiation between public and private options when preferences are heterogeneous ii whether contract design encourages choice of private insurance before information about risk is revealed i explore the role of these factors empirically within the unique institutional setting of the german health insurance system using a fuzzy regression discontinuity design to disentangle adverse selection and moral hazard i find no compelling support for extensive cream skimming of public option by private insurers despite their ability to fully underwrite risk a model of demand for private insurance supports the idea that heterogeneity in non pecuniary preferences and long term structure of private insurance contracts may be muting cream skimming in this setting

why do larger buyers pay lower prices intense supplier competition abstract the paper provides a theoretical explanation of the common claim that larger buyers pay lower prices in the model suppliers compete more aggressively for the business of larger buyers much as they do in boom periods of rotemberg and saloner

experiments on percolation of information in dark markets in dark markets order submissions are bilateral and transaction prices are known only to the trading counterparties here we study to what extent the information aggregation theory proposed by duffie and collaborators predicts outcomes in a laboratory version of such markets we find that prices aggregate the available information but not in the strict sense of the theory where prices converge exponentially fast to average private signals prices instead fluctuate within bands around this average the band widths reflect in the best case the precision of the average signal and otherwise the precision of a single private signal

on the emergent properties of artificial stock markets the efficient market hypothesis and the rational expectations hypothesis abstract by studying two well known hypotheses in economics this paper illustrates how emergent properties can be shown in an agent based artificial stock market the two hypotheses considered are the efficient market hypothesis and the rational expectations hypothesis we inquire whether the macrobehavior depicted by these two hypotheses is consistent with our understanding of the microbehavior in this agent based model genetic programming is applied to evolving a population of traders learning over time we first apply a series of econometric tests to show that the emh and the reh can be satisfied with some portions of the artificial time series then by analyzing traders behavior we show that these aggregate results cannot be interpreted as a simple scaling up of individual behavior a conjecture based on sunspot like signals is proposed to explain why macrobehavior can be very different from microbehavior we assert that the huge search space attributable to genetic programming can induce sunspot like signals and we use simulated evolved complexity of forecasting rules and granger causality tests to examine this assertion