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

learning about a new technology pineapple in ghana this paper investigates the role of social learning in the diffusion of a new agri cultural technology in ghana we use unique data on farmers communication patterns to define each individual s information neighborhood conditional on many potentially confounding variables we find evidence that farmers adjust their inputs to align with those of their information neighbors who were surpris ingly successful in previous periods the relationship of these input adjustments to experience further indicates the presence of social learning in addition applying the same method to input choices for another crop of known technol ogy correctly indicates an absence of social learning effects jel d83 013 033 q16

household electricity demand revisited respond to price changes this paper develops a model for evaluating the effects of alternative tariff designs on electricity use the model concurrently addresses several interrelated difficulties posed by nonlinear pricing heterogeneity in consumer price sensitivity and consumption aggregation over appliances and time we estimate the model using extensive data for a representative sample of 1300 california households the results imply a strikingly skewed distribution of household electricity price elasticities in the population with a small fraction of households accounting for most aggregate demand response we then estimate the aggregate and distributional consequences of recent tariff structure changes recent efforts to restructure electricity markets have renewed interest in electricity demand and pricing this interest reflects a broad desire to improve the efficiency of electricity markets and policy makers concerns over the impact of price changes on consumers how new pricing mechanisms would affect households consumption and expenditures is a matter of considerable uncertainty however this uncertainty has provoked controversy and debate in the regulatory policy arena hampering market reforms using econometric methods to assess the effects of electricity price changes presents several challenges these include the nonlinear structure of tariff schedules aggregation of metered consumption behaviour over time and appliances and the interdependence of energy use with longer term household decisions over appliance ownership and dwelling characteristics the first two issues introduce complex simultaneity problems between marginal prices and consumption the third issue imposes high data requirements information on household specific appliance holdings and residence features and creates heterogeneity in consumption responses related to the characteristics of these durable goods when the researcher s objective is to develop a model for simulating the effects of prospective tariff changes ignoring these issues will provide an incomplete assessment of demand responses and potentially misleading predictions of a new tariff s consumption and revenue consequences in this paper we estimate a model of household electricity demand that can be used

game shows and economic behavior risk taking on card sharks this paper studies individual risk taking behavior with a unique data set risky decisions of contestants during the threeyear history of the television game show card sharks in the bonus round of the game individuals choose how much to wager on positive expected value gambles with known and varying probabilities and large possible payouts since no special skills or knowledge are involved empirical analysis is not complicated by a contestant s superior information about her own abilities stakes can reach 16 000 and average 3 200 few experimental budgets permit even one observation of this magnitude first i simply estimate how risk averse contestants behave under the assumption of expected utility maximization i estimate a lower bound for the coefficient of absolute risk aversion of 0 00031 which when multiplied by per capita u s personal income gives an estimate of relative risk aversion of 4 8 this estimate is higher than most econometric estimates of risk aversion contestants however do not act in a manner consistent with expected utility maximization so this number should not be given a structural interpretation rather it is simply a useful way to summarize average willingness to bear risk of individuals on the show second i explore how individual behavior is inconsistent with expected utility theory the amount a contestant wishes to wager depends critically on the amount of wealth she has accumulated in the bonus round and therefore on the size of the stakes this is at odds with expected utility theory since the size of the stakes although far from insignificant is small relative to a person s wealth contestants should then have close to constant absolute risk aversion with respect to accumulated winnings in the game a more striking result deals with contestants who had previ

social norms and energy conservation beyond the us abstract the seminal studies by allcott and mullainathan 2010 allcott 2011 and allcott and rogers 2014 show that social comparison based home energy reports her are a cost effective climate policy intervention in the us our paper demonstrates the context dependency of this result in most industrialized countries average electricity consumption and carbon intensity are well below us levels consequently her interventions can only become cost effective if treatment effect sizes are substantially higher for germany we provide evidence from a large scale randomized controlled trial that effect sizes are in fact considerably lower than in the us we conclude by illustrating that targeting highly responsive subgroups is crucial to reach cost effectiveness and by identifying the few countries in which her are promising policy instruments

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

economics of alliances the lessons for collective action this essay provides an up to date summary of the findings of the literature on the economics of alliances we show that the study of the economics of alliances has played a pivotal role in understanding and applying public good analysis to real world applications we establish that the manner in which alliances address burden sharing and allocative issues is related to strategic doctrines weapon technology perceived threats and membership composition past contributions are evaluated and areas needing further development are identified the theoretical and empirical knowledge gained from the study of alliances is shown to be directly applicable to a wide range of international collectives

the short run and long run effects of behavioral interventions experimental evidence from energy conservation we document three remarkable features of the opower program in which social comparison based home energy reports are repeatedly mailed to more than six million households nationwide first initial reports cause high frequency action and backsliding but these cycles attenuate over time second if reports are discontinued after two years effects are relatively persistent decaying at 10 20 percent per year third consumers are slow to habituate they continue to respond to repeated treatment even after two years we show that the previous conservative assumptions about post intervention persistence had dramatically understated cost effectiveness and illustrate how empirical estimates can optimize program design jel d12 d83 l94 q41

switching costs price sensitivity and health plan choice we investigate the extent to which sensitivity to health plan premiums differs across individuals according to characteristics related to the cost of switching plans our results indicate substantial variation in price sensitivity related to expected health care costs younger healthier employees are between two and four times more sensitive to price than employees who are older and who have been recently hospitalized or diagnosed with cancer we also find evidence of status quo bias estimated premium elasticities are significantly higher for new hires than for incumbent employees simulations combining our results with actuarial data illustrate the cost implications of risk related differences in price elasticity

pricing and welfare in health plan choice premiums in health insurance markets frequently do not reflect individual differences in costs either because consumers have private information or because prices are not risk rated this creates inefficiencies when consumers self select into plans we develop a simple econometric model to study this problem and estimate it using data on small employers we find a welfare loss of 2 11 percent of coverage costs compared to what is feasible with risk rating only about one quarter of this is due to inefficiently chosen uniform contribution levels we also investigate the reclassification risk created by risk rating individual incremental premiums finding only a modest welfare cost

dominated choices and medicare advantage enrollment research in behavioral economics suggests that certain circumstances such as large numbers of complex options or revisiting prior choices can lead to decision errors this paper explores the enrollment decisions of medicare beneficiaries in the medicare advantage ma program during the time period we study 2007 2010 private fee for service pffs plans offered enhanced benefits beyond those of traditional medicare tm without any restrictions on physician networks making tm a dominated choice relative to pffs yet more than three quarters of medicare beneficiaries remained in tm during our study period we analyze the role of status quo bias in explaining this pattern of enrollment our results suggest that status quo bias plays an important role the rate of ma enrollment was significantly higher among new medicare beneficiaries than among incumbents these results illustrate the importance of the choice environment that is in place when enrollees first enter the medicare program

comparison friction experimental evidence from medicare drug plans consumers need information to compare alternatives for markets to function efficiently recognizing this public policies often pair competition with easy access to comparative information the implicit assumption is that comparison friction the wedge between the availability of comparative information and consumers use of it is inconsequential because information is readily available and consumers will access this information and make effective choices we examine the extent of comparison friction in the market for medicare part d prescription drug plans in the united states in a randomized field experiment an intervention group received a letter with personalized cost information that information was readily available for free and widely advertised however this additional step providing the information rather than having consumers actively access it had an impact plan switching was 28 percent in the intervention group versus 17 percent in the comparison group and the intervention caused an average decline in predicted consumer cost of about 100 per year among letter recipients roughly 5 percent of the cost in the comparison group our results suggest that comparison friction can be large even when the cost of acquiring information is small and may be relevant for a wide range of public policies that incorporate consumer choice

rational expectations and the aggregation of diverse information in laboratory security markets the idea that markets might aggregate and disseminate information and also resolve conflicts is central to the literature on decentralization hurwicz 1972 and rational expectations lucas 1972 we report on three series of experiments all of which were predicted to have performed identically by the theory of rational expectations in two of the three series one in which participants trade a complete set of arrow debreu securities and a second in which all participants have identical preferences double auction trading leads to efficient aggregation of diverse information and rational expectations equilibrium failure of the third series to exhibit such convergence demonstrates the importance of market institutions and trading instruments in achievement of equilibrium

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

physician payments under health care reform abstract this study examines the impact of major health insurance reform on payments made in the health care sector we study the prices of services paid to physicians in the privately insured market during the massachusetts health care reform the reform increased the number of insured individuals as well as introduced an online marketplace where insurers compete we estimate that over the reform period physician payments increased at least 11 percentage points relative to control areas payment increases began around the time legislation passed the house and senate the period in which their was a high probability of the bill eventually becoming law this result is consistent with fixed duration payment contracts being negotiated in anticipation of future demand and competition

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

markets transparency and the corporate bond market for decades corporate bonds primarily traded in an opaque environment quotations which indicate prices at which dealers are willing to transact were available only to market professionals most often by telephone prices at which bond transactions were completed were not made public the u s corporate bond market became much more transparent with the introduction of the transaction reporting and compliance engine trace in july 2002 beginning that date bond dealers were required to report all trades in publicly issued corporate bonds to the national association of security dealers which in turn made transaction data available to the public in this paper we describe trading protocols in the corporate bond market and assess the impact of the increase in transparency on the market we review how trace has affected the costs that corporate bond investors paid to bond dealers for their transactions we canvass the opinions of a variety of finance professionals and consider articles in the trade press to obtain a broader view of the impact of transparency on the corporate bond market

economic models as analogies people often wonder why economists analyse models whose assumptions are known to be false while economists feel that they learn a lot from such exercises we suggest that part of the knowledge generated by academic economists is case based rather than rule based that is instead of offering general rules or theories that should be contrasted with data economists often analyse models that are theoretical cases which help understand economic problems by drawing analogies between the model and the problem thus economic models empirical data experimental results and other sources of knowledge are all on equal footing that is they all provide cases to which a given problem can be compared we offer complexity arguments that explain why case based reasoning may sometimes be the method of choice and why economists prefer simple cases many economists think of their discipline as a successful social science economics relies on rigorous and non trivial mathematical and statistical analyses the paradigm of microeconomics is viewed as a unified approach that can deal with all problems of social interaction and it is indeed adopted by other disciplines economics is popular with students and economics professors are in high demand within the academic world and outside it 1 however the basic assumptions of economic theories have been harshly criticised by psychologists presumably showing in laboratory experiments that these assumptions frequently do not hold if the assumptions of economics are all wrong why do economists keep using them why do they develop sophisticated mathematical models based on such flimsy foundations this question is our starting point we elaborate on it and discuss two additional puzzles in section 1 we then offer a possible resolution to these puzzles in section 2 namely that some of the reasoning in economics is casebased rather than rule based and that economists view themselves as generating the cases to which real problems might be analogous true to the method of our discipline we construct a model in section 4 that illustrates the advantages of this mode of research in section 5 we discuss the virtues of a general paradigm or to be precise of the standard language that such a paradigm employs section 6 concludes

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

knowledge is less power experimental evidence from residential energy use abstract imperfect information about product attributes inhibits efficiency in many choice settings but can be overcome by providing simple low cost information we use a randomized control trial to test the effect of high frequency information about residential electricity usage on the price elasticity of demand informed households are three standard deviations more responsive to temporary price increases an effect that is not attributable to price salience conservation extends beyond pricing events in the short and medium run providing evidence of habit formation and implying that the intervention leads to greenhouse gas abatement survey evidence suggests that information facilitates learning jel d12 d83 l11 l94 q41 q54

modelling the heterogeneous effects of stocking rate on dairy production an application of unconditional quantile regression with fixed effects this article analyses the effects of stocking rate on dairy production using new zealand dairy farm business data for the period 2005 2014 unlike previous studies that assume a homogenous relatio

information percolation in segmented markets we study equilibria of dynamic over the counter markets in which agents are distinguished by their preferences and information over time agents are privately informed by bids and offers investors differ with respect to information quality including initial information precision and also in terms of market connectivity the expected frequency of their bilateral trading opportunities we characterize endogenous information acquisition and show how learning externalities affect information gathering incentives more liquid markets lead to higher equilibrium information acquisition when the gains from trade and market duration are sufficiently large on the other hand for a small market duration the opposite may occur if agents vary sufficiently in terms of their market connectivity c 2014 published by elsevier inc

health insurance for humans information frictions plan choice and consumer welfare traditional models of insurance choice are predicated on fully informed and rational consumers protecting themselves from exposure to financial risk in practice choosing an insurance plan is a complicated decision often made without full information in this paper we combine new administrative data on health plan choices and claims with unique survey data on consumer information to identify risk preferences information frictions and hassle costs our additional friction measures are important predictors of choices and meaningfully impact risk preference estimates we study the implications of counterfactual insurance allocations to illustrate the importance of distinguishing between these micro foundations for welfare analysis

nudges in the marketplace the response of household electricity consumption to information and monetary incentives this paper provides field evidence from india examining changes in electricity consumption in response to various behavioral interventions i study the impact of i weekly reports with peer comparisons of electricity use ii reports augmented with monetary incentives to reduce consumption and iii price variation i estimate consumption changes using a randomized control trial in conjunction with a quasi experiment households provided reports alone reduced summer season consumption by 7 percent price elasticity identified from cross sectional and time series variation was estimated at 0 56 against this benchmark the impact of peer comparisons alone was equivalent to increasing tariffs by about 12 5 percent counter intuitively when weekly reports were augmented with monetary incentives rewarding electricity conservation households no longer reduced consumption households receiving reports also show higher price elasticity relative to controls these results provide new evidence identifying the response of developing country consumers to behavioral interventions while examining the interaction of prices incentives and information

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

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

optimal mandates and the welfare cost of asymmetric information evidence from the u k annuity market much of the extensive empirical literature on insurance markets has focused on whether adverse selection can be detected once detected however there has been little attempt to quantify its welfare cost or to assess whether and what potential government interventions may reduce these costs to do so we develop a model of annuity contract choice and estimate it using data from the u k annuity market the model allows for private information about mortality risk as well as heterogeneity in preferences over different contract options we focus on the choice of length of guarantee among individuals who are required to buy annuities the results suggest that asymmetric information along the guarantee margin reduces welfare relative to a first best symmetric information benchmark by about 127 million per year or about 2 percent of annuitized wealth we also find that by requiring that individuals choose the longest guarantee period allowed mandates could achieve the first best allocation however we estimate that other mandated guarantee lengths would have detrimental effects on welfare since determining the optimal mandate is empirically difficult our findings suggest that achieving welfare gains through mandatory social insurance may be harder in practice than simple theory may suggest

is more information always better experimental financial markets with cumulative information abstract we study the value of information in financial markets by asking whether having more information always leads to higher returns we address this question in an experiment where information about an asset s intrinsic value is cumulatively distributed among traders we find that only the very best informed traders i e insiders significantly outperform less informed traders however there is a wide range of information levels from zero information to above average information levels where additional information does not yield higher returns the latter result implies that the value of additional information need not be strictly positive

eight questions about brain drain high skilled emigration is an emotive issue that in popular discourse is often referred to as brain drain conjuring images of extremely negative impacts on developing countries recent discussions of brain gain diaspora effects and other advantages of migration have been used to argue against this but much of the discussion has been absent of evidence this paper builds upon a new wave of empirical research to answer eight key questions underlying much of the brain drain debate 1 what is brain drain 2 why should economists care about it 3 is brain drain increasing 4 is there a positive relationship between skilled and unskilled migration 5 what makes brain drain more likely 6 does brain gain exist 7 do high skilled workers remit invest and share knowledge back home and 8 what do we know about the fiscal and production externalities of brain drain

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 diffusion of new agricultural technologies the case of crossbred cow technology in tanzania the recent literature on agricultural technology adoption shows that diffusion of new technologies varies significantly across space and time furthermore puzzles exist about why some seemingly profitable technologies are not adopted especially in livestock production we employ a hazard or duration function to explain diffusion of crossbred cow technology in a unique sample of tanzania farmers a farmer s adoption of crossbred technology depends positively on the proximity of his farm to other users on his schooling and on his access to credit and contact with extension agents

information revelation in a market with pairwise meetings the paper presents a simple pairwise meetings model of trade the new feature is that agents have asymmetric information about the true state of the world the focus is on the transmission of the information through the process of trade the qualitative question is to what extent is the information revealed to uninformed agents through the trading process when the market is in some sense frictionless in particular does the decentralized process give rise to full revelation results as derived by the literature on rational expectations for centralized and competitive environments in the context of the model of this paper it turns out that the information is not fully revealed to uninformed agents even when the market is in some sense approximately frictionless

adverse selection and inertia in health insurance markets when nudging hurts this paper investigates consumer inertia in health insurance markets where adverse selection is a potential concern we leverage a major change to insurance provision that occurred at a large firm to identify substantial inertia and develop and estimate a choice model that also quantifies risk preferences and ex ante health risk we use these estimates to study the impact of policies that nudge consumers toward better decisions by reducing inertia when aggregated these improved individual level choices substantially exacerbate adverse selection in our setting leading to an overall reduction in welfare that doubles the existing welfare loss from adverse selection jel d82 g22 i13 a number of potential impediments stand in the way of efficient health insur ance markets the most noted of these is adverse selection first studied by akerlof 1970 and rothschild and stiglitz 1976 in insurance markets prices reflect the expected risk costs of the insured pool whether the reason is price regulation or private information when insurers cannot price all risk characteristics riskier consumers choose more comprehensive health plans this causes the equilibrium prices of these plans to rise and healthier enrollees to select less comprehensive coverage than they would otherwise prefer

patient cost sharing and hospitalization offsets in the elderly in the medicare program increases in cost sharing by a supplemental insurer can exert financial externalities we study a policy change that raised patient cost sharing for the supplemental insurer for retired public employees in california we find that physician visits and prescription drug usage have elasticities that are similar to those of the rand health insurance experiment hie unlike the hie however we find substantial offset effects in terms of increased hospital utilization the savings from increased cost sharing accrue mostly to the supplemental insurer while the costs of increased hospitalization accrue mostly to medicare

information percolation in large markets we introduce a simple model of the percolation of information of common interest through a large market as agents encounter each other over time and reveal information to each other some of which they may have received earlier from other agents we are particularly interested in the evolution over time of the cross sectional distribution in the population of the posterior probability assignments of the various agents we provide a market example based on privately held auctions and obtain a relatively explicit solution for the cross sectional distribution of posterior beliefs at each time our results contribute to the literature on information transmission in markets hayek 1945 argues that markets allow information that is dispersed in a population to be revealed through prices grossman s 1981 notion of a rational expectations equilibrium formalizes this idea in a setting with price taking agents milgrom 1981 pesendorfer and swinkels 1997 and reny and perry 2006 provide strategic foundations for the rational expectations equilibrium concept in centralized markets a number of important markets however are decentralized these include over the counter markets and private auction markets wolinsky 1990 and blouin and serrano 2002 study information transmission in decentralized markets in contrast to these two papers equilibrium behavior in our market example leads to full revelation of information we happily acknowledge conversations with manuel amador frank kelly jeremy stein and pierre olivier weill and research assistance from sergey lobanov rubinstein and wolinsky 1985 and gale 1986a 1986b study decentralized markets without asymmetric information satterthwaite and shneyerov 2003 study decentralized market with private value asymmetric information amador and weill 2006 study a more abstract setting regarding transmission of common and private i nformation

is the motherhood penalty larger for low wage women a comment on quantile regression in this comment we offer a nontechnical discussion of conventional conditional multivariate quantile regression with an emphasis on the appropriate interpretation of results we discuss its distinction from unconditional quantile regression an analytic method that can be used to estimate varying associations between predictors and outcome at different points of the outcome distribution we argue that the research question posed by budig and hodges 2010 whether the motherhood penalty is larger for low wage women cannot be answered with the authors conditional quantile regression models using more appropriate unconditional quantile regression models we find in contrast to budig and hodges s claims that the motherhood penalty is not largest for low wage women

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

information percolation with equilibrium search dynamics we solve for the equilibrium dynamics of information sharing in a large population each agent is endowed with signals regarding the likely outcome of a random variable of common concern individuals choose the effort with which they search for others from whom they can gather additional information when two agents meet they share their information the information gathered is further shared at subsequent meetings and so on equilibria exist in which agents search maximally until they acquire sufficient information precision and then search minimally a tax whose proceeds are used to subsidize the costs of search improves information sharing and can in some cases increase welfare on the other hand endowing agents with public signals reduces information sharing and can in some cases decrease welfare

the impacts of energy efficiency policies meta analysis abstract this paper attempts to quantitatively summarize the existing empirical evidence on the effects of energy efficiency policies on energy demand and on the price of associated durable goods as well as to identify the main factors that systematically affect the estimated impacts to this end a meta regression analysis of the effects of energy efficiency policies is carried out on the basis of an extensive review of the existing literature selecting those studies that analyze the impact of energy efficiency policies with respect to a business as usual setting taking into account the econometric problems associated with this type of analysis intra class correlation cross sectional dependence publication bias in pursuit of robust outcomes the results show that the studies analyzing the effects of energy efficiency policies estimate a significant impact of these policies on energy demand 10 5 8 8 and the price of related durable goods 7 9 6 the main factors that influence results are the policy instrument the targeted sector the type of country the analyzed period the consideration of free riders and the type of analysis data and publication energy demand and the sector and analyzed period price of durables

game theory and empirical generalizations concerning competitive promotions this paper offers the generalization that competitive promotions are mixed strategies first an empirical regularity is established that promotions are independent across competitors this regularity is then elaborated on in the context of a promotion game the promotion game is linked to observable outcomes and a classification of possible situations is developed in particular the classification includes the prisoners dilemma battle of the sexes and marketing models of promotion competition the evidence for the generalization comes from a variety of product markets spanning trade promotions retail price reductions and retail promotions such as advertised specials the product markets include coffee baby diapers toilet tissue saltines dishwashing fluid ketchup and detergents among others the data in some cases were from cooperating grocery chains and in others from iri scanner panels the evidence from extant research and from new analyses is presented each situation is identified as be

corporate bond market transaction costs and transparency using a complete record of u s over the counter otc secondary trades in corporate bonds we estimate average transaction costs as a function of trade size for each bond that traded more than nine times between january 2003 and january 2005 we find that transaction costs decrease significantly with trade size highly rated bonds recently issued bonds and bonds close to maturity have lower transaction costs than do other bonds costs are lower for bonds with transparent trade prices and they drop when the trace system starts to publicly disseminate their prices the results suggest that public traders benefit significantly from price transparency