bidder preferences among auction institutions i introduction auctions have become a pervasive method of exchange in the online world as each day thousands of auctions take place online and this trade volume totals to billions of dollars worth of goods per year 1 this large volume of auction transactions implies the existence of a large number of sellers competing for buyers the obvious implication is that the competition among the sellers for the pool of potential buyers can be fierce and any competitive edge a seller can find could be important one such competitive edge a seller might exploit is using an auction design that attracts bidders away from their competitors when designing a real auction or modeling a theoretical one the entry decision of prospective bidders is rarely considered most auction analysis is performed assuming that a certain number of bidders will participate for certain or perhaps that the number of bidders is unknown and randomly determined it should be clear however that the most crucial part of a successful auction is encouraging as many bidders as possible to participate in general this should be expected to have a positive effect on revenue at least in noncommon value environments and in certain types of auctions it may help combat the possibility of bidder collusion because there are typically competing auctions available for similar goods or even outside options that bidders can pursue when auctions are for unique goods it is important to understand how the aspects of an auction format can effect the entry decision of a bidder consider a bidder who is faced with the choice of entering one of two auctions for similar or even identical objects how does this bidder make the decision of which auction to enter the obvious answer is that the bidder will enter into the auction that maximizes his or her expected utility so long as that expected utility is greater than some reservation value the real question then is how are these expected utilities constructed profit from participating in the auction is an obvious argument there are also a number of environmental considerations that might effect this decision that would be difficult to account for precisely such as the reputation and trustworthiness of the auctioneer quality of the advertisement for the auction and things of this nature it is also possible that the format of the auction itself can have an impact on the preferences of the bidder this latter point will be the issue of this study the particular focus will be looking at bidder preferences between the two most common standard auction formats used in the field the sealed bid first price will be abbreviated as just the sealed bid auction and the ascending or english auction the other reason we are interested in comparing these two auction formats rather than the ascending and second price or first price and descending is that it seems reasonable to expect bidders to have preferences between the two due to the strategic differences between them such differences lead to substantial differences in terms of the difficulty of deciding how to bid and also in the possibility that an outcome leads to a bidder experiencing some form of regret regret may occur in a first price auction when a bidder loses to a bid that is below his value as he may think that if only he had bid higher he could have won although such feelings of regret may be considered irrational that does not preclude their existence such a scenario should not reasonably occur in an ascending auction if one considers the situation of a bidder choosing between two auctions that differ only in regard to whether the auction is being conducted according to an ascending or sealed bid format it is not immediately obvious which would be the most preferred even assuming a standard symmetric independent private values environment were all bidders risk neutral then of course revenue equivalence would hold and the bidders would be indifferent

how to set minimum acceptable bids with an application to real estate auctions in a general auction model with affiliated signals common components to valuations and endogenous entry we compute the equilibrium bidding strategies and outcomes and derive a lower bound on the optimal reserve price this lower bound can be computed using data on past auctions combined with information about the subsequent sales prices of unsold goods we illustrate how to compute the lower bound using data from real estate auctions

taxing capital not a bad idea after all we quantitatively characterize the optimal capital and labor income tax in an overlapping generations model with idiosyncratic uninsurable income shocks and permanent productivity difierences of households the optimal capital income tax rate is signiflcantly positive at 36 percent the optimal progressive labor income tax is roughly a at tax of 23 percent with a deduction of 7 200 relative to average household income of 42 000 the high optimal capital income tax is mainly driven by the life cycle structure of the model whereas the optimal progressivity of the labor income tax is attributable to the insurance and redistribution role of the tax system jel e62 h21 h24

market clearing with stochastic security part i formulation the first of this two paper series formulates a stochastic security constrained multi period electricity market clearing problem with unit commitment the stochastic security criterion accounts for a pre selected set of random generator and line outages with known historical failure rates and involuntary load shedding as optimization variables unlike the classical deterministic reserve constrained unit commitment here the reserve services are determined by economically penalizing the operation of the market by the expected load not served the proposed formulation is a stochastic programming problem that optimizes concurrently with the pre contingency social welfare the expected operating costs associated with the deployment of the reserves following the contingencies this stochastic programming formulation is solved in the second companion paper using mixed integer linear programming methods two cases are presented a small transmission constrained three bus network scheduled over a horizon of four hours and the ieee reliability test system scheduled over 24 h the impact on the resulting generation and reserve schedules of transmission constraints and generation ramp limits of demand side reserve of the value of load not served and of the constitution of the pre selected set of contingencies are assessed

equilibrium in auctions with entry the authors model entry incentives in auctions with risk neutral bidders and characterize a symmetric equilibrium in which the number of entrants is stochastic the presence of too many potential bidders raises coordination costs that detract from welfare the authors show that the seller and society can benefit from policies that reduce market thickness i e the relative abundance of buyers their analysis extends well known revenue equivalence and ranking theorems but also demonstrates that variations in the auction environment affect optimal policies e g reservation prices in ways not anticipated by models that ignore entry copyright 1994 by american economic association

consumer debt non payment and the borrowing constraint implications for consumer behavior abstract this paper examines whether the consumption behavior of a borrowing constrained household is affected by debt non payment from the household s intertemporal maximization problem we derive a two equation model consisting of augmented forms of the standard consumption euler equation and the static labor supply equation we estimate these equations by using nonlinear gmm and obtain estimates inter alia for the discount factor and the debt payment to income ratio the former is found to be much lower than the values often used in model calibrations in the literature showing a high degree of impatience of households the latter is close to the values reported in the consumer credit literature our results are found to be robust to a number of specification tests under different types of household preferences these results are also subjected to a comparative analysis with the results derived from the consumption euler equation under full debt repayment and no borrowing constraint

the hyperbolic consumption model calibration simulation and empirical evaluation ur preferences for the long run tend to conflict with our short run behavior when planning for the long run we intend to meet our deadlines exercise regularly and eat healthfully but in the short run we have little interest in revising manuscripts jogging on the stairmaster and skipping the chocolate souffleala mode delay of gratification is a nice long term goal but instant gratification is disconcertingly tempting this gap between long run intentions and short run actions is apparent across a wide range of behaviors including saving choices a 1997 survey found that 76 percent of respondents believe they should be saving more for retirement looking only at respondents who believed they were at an age where you should be seriously saving already the survey found that 55 percent reported being behind in their savings and only 6 percent reported being ahead farkas and johnson 1997 the report on the survey concluded t he gaps between people s atti tudes intentions and behavior are troubling and threaten increased insecurity and dissatisfaction for people when they retire americans are simply not doing what logic and their own reasoning suggests they should be doing a 1993 luntz webber merrill lynch survey found similar answers when baby boomers were asked what percentage of your annual household income do you think you should save for retirement and what percentage of your annual

distributed stochastic market clearing with high penetration wind power integrating renewable energy into the modern power grid requires risk cognizant dispatch of resources to account for the stochastic availability of renewables toward this goal day ahead stochastic market clearing with high penetration wind energy is pursued in this paper based on the dc optimal power flow opf the objective is to minimize the social cost which consists of conventional generation costs end user disutility as well as a risk measure of the system re dispatching cost capitalizing on the conditional value at risk cvar the novel model is able to mitigate the potentially high risk of the recourse actions to compensate wind forecast errors the resulting convex optimization task is tackled via a distribution free sample average based approximation to bypass the prohibitively complex high dimensional integration furthermore to cope with possibly large scale dispatchable loads a fast distributed solver is developed with guaranteed convergence using the alternating direction method of multipliers admm numerical results tested on a modified benchmark system are reported to corroborate the merits of the novel framework and proposed approaches

a stochastic electricity market clearing formulation with consistent pricing properties we argue that deterministic market clearing formulations introduce arbitrary distortions between day ahead and expected real time prices that bias economic incentives we extend and analyze a previously proposed stochastic clearing formulation in which the social surplus function induces penalties between day ahead and real time quantities we prove that the formulation yields price bounded price distortions and we show that adding a similar penalty term to transmission flows and phase angles ensures boundedness throughout the network we prove that when the price distortions are zero day ahead quantities equal a quantile of their real time counterparts the undesired effects of price distortions suggest that stochastic settings provide significant benefits over deterministic ones that go beyond social surplus improvements we propose additional metrics to evaluate these benefits

time inconsistent preferences and social security in this paper we examine the role of social security in an economy populated by overlapping generations of individuals with time inconsistent preferences who face mortality risk individual income risk and borrowing constraints we find that unfunded social security lowers the capital stock output and consumption for consumers with time consistent or time inconsistent preferences however it may raise or lower welfare depending on the strength of time inconsistency

payday loans and credit cards new liquidity and credit scoring puzzles using a unique dataset matched at the individual level from two administrative sources we examine household choices between liabilities and assess the informational content of prime and subprime credit scores in the consumer credit market first more specifically we assess consumers effectiveness at prioritizing use of their lowest cost credit option we find that most borrowers from one payday lender who also have a credit card from a major credit card issuer have substantial credit card liquidity on the days they take out their payday loans this is costly because payday loans have annualized interest rates of at least several hundred percent though perhaps partly explained by the fact that borrowers have experienced substantial declines in credit card liquidity in the year leading up to the payday loan second we show that fico scores and teletrack scores have independent information and are specialized for the types of lending where they are used teletrack scores have eight times the predictive power for payday loan default as fico scores we also show that prime lenders should value information about their borrowers subprime activity taking out a payday loan predicts nearly a doubling in the probability of serious credit card delinquency over the next year this abstract was borrowed from another version of this item

how valuable is a good reputation a sample selection model of internet auctions on the online auction site ebay by convention sellers do not ship goods to winning bidders until after they have received payment so there is an opportunity for sellers to take advantage of bidders trust realizing this the designers of ebay created a system that relies on self enforcement using reputation several recent studies have found that bidders give little or no reward to sellers who have better reputations i show that in fact sellers are strongly rewarded for the first few reports that they have behaved honestly but marginal returns to additional reports are severely decreasing

uncertainty management in the unit commitment problem uncertainty in power systems operations has been traditionally managed by multistage decision making and operating reserve requirements a familiar example of multistage decisions is day ahead unit commitment and real time economic dispatch an alternate approach for managing uncertainty is a stochastic formulation which allows the explicit modeling of the sources of uncertainty this paper compares stochastic and reserve methods and evaluates the benefits of a combined approach for the efficient management of uncertainty in the unit commitment problem numerical studies show that unit commitment solutions obtained for the combined approach are robust and superior with respect to the traditional approach in terms of both economics and reliability metrics

pricing electricity through a stochastic non convex market clearing model this paper proposes a pricing scheme for the day ahead market in power systems with a large percentage of renewable stochastic production to clear the day ahead market instead of a simplistic deterministic model we use a two stage stochastic programming model that embodies a prognosis of future operating conditions non convexities due to start up costs and the on off status of generators and their minimum power outputs are properly taken into account our goal is to obtain uniform day ahead clearing prices that deviate in the least possible manner from marginal prices and that allow producers to recover their costs without uplifts the proposed methodology is illustrated using a simple example and a realistic case study

economic insights from internet auctions this paper surveys recent studies of internet auctions four main areas of research are summarized first we survey several studies that document and attempt to explain the frequently observed sniping or last second bidding behavior in these auctions second we summarize several methods proposed to quantify the distortions caused by asymmetric information in these markets most notably due to the winner s curse third we explore research about the role of reputation mechanisms installed to help combat these distortions finally we discuss what internet auctions have to teach us about auction design

frictions in internet auctions with many traders a counterexample abstract we show that when frictions are present the peters and severinov 2006 ps bidding rule is no longer efficient nor a pbe of the ps game researchers should be cautious when using the ps bidding rule in markets with frictions like ebay

search costs and equilibrium price dispersion in auctions a leading explanation for price dispersion in posted price markets is search costs we incorporate this insight into a model of competing second price auctions similar to ebay by doing so we extend the narrow literature on competing auctions to capture price dispersion and grow the already large literature on price dispersion to include auctions we provide evidence on search costs and price dispersion using data collected from ebay identifying search costs by exploiting a discontinuity in the visibility of auctions due to ebay s search tool 1 we thank aaron bodoh creed greg lewis steve tadelis and various seminar participants for helpful comments nate woody for programming assistance and the cornell university institute for social sciences for financial support the views expressed herein are solely those of the authors and do not necessarily reflect those of the u s department of justice 1

discretionary monetary and fiscal policy with endogenous sovereign risk abstract how does the presence of sovereign risk affect the conduct of public policy to answer this question this paper studies optimal monetary and fiscal policy without commitment for a model economy with nominal public debt and strategic sovereign default compared to an economy without the possibility of default economies with sovereign risk experience more volatile interest rates which impedes the government s ability to smooth tax rates across states risk of default also limits public debt accumulation reducing the government s incentive to use surprise inflation on average when calibrated to the united states the model predicts that a counterfactual increase in the average annual default probability from 0 to 1 lowers average inflation by 33 raises the standard deviation of inflation by 18 and increases the standard deviation of the labor income tax by 73 the transmission of exogenous shocks to real aggregate quantities is however almost unaffected by the possibility of default for example the presence of sovereign risk would increase the standard deviation of log real gdp by less than 1 in the experiment above similarly the welfare consequences of sovereign risk are found to be of negligible size as well

equilibrium bid functions for auctions with an uncertain number of bidders abstract the number of rivals may be unknown when a bidding strategy is formulated in an auction in a symmetric model with risk neutral bidders holding independent information we obtain explicit equilibrium bidding functions for first price and second price auctions with uncertainty about the number of rivals five auctions are revenue equivalent first price and second price auctions each with the number of bidders known or uncertain and english auctions

selling online versus live a seller choosing between auctioning online and live faces a tradeoff lower transaction costs online against more rents left with the bidders we model this tradeoff and apply the theory to auctions of art the crucial parameter for whether the seller does better online than live is not the expected price but the valuation uncertainty

consumer bankruptcy a fresh start consumer bankruptcy provides partial insurance against bad luck but by driving up interest rates makes life cycle smoothing more difficult we argue that to assess this trade off one needs a quantitative model of consumer bankruptcy with three key features life cycle component idiosyncratic earnings uncertainty and expense uncertainty exogenous negative shocks to household balance sheets we find that transitory and persistent earnings shocks have very different implications for evaluating bankruptcy rules more persistent shocks make the bankruptcy option more desirable larger transitory shocks have the opposite effect our findings suggest the current us bankruptcy system may be desirable for reasonable parameter values jel d14 d91 k35

welfare implications of the bankruptcy reform act of 1999 abstract in recent years personal bankruptcy has become an important issue to consumers creditors and legislators alike over 40 billion dollars of unsecured debt were discharged in 1998 by 1 44 million households these losses have led legislators to propose a variety of changes in bankruptcy law the most important and recent of which is the bankruptcy reform act of 1999 ba99 i develop a dynamic stochastic general equilibrium model of personal bankruptcy to investigate the trade off between the consumption smoothing role of bankruptcy and the interest rate and deadweight costs it imposes i find that stringent means tests would reduce filing rates only slightly and would have only modest welfare consequences on the other hand the elimination of bankruptcy altogether is found to have substantial benefits this result is robust to income shock persistence and to stringency in the application of means tests

assessing bankruptcy reform in a model with temptation and equilibrium default abstract a life cycle model with equilibrium default in which agents with and without temptation coexist is constructed to evaluate the 2005 bankruptcy law reform the calibrated model indicates that the 2005 reform reduces bankruptcies as seen in the data and improves welfare as lower default premia allows better consumption smoothing a counterfactual reform of changing income garnishment rate is also investigated interesting contrasting welfare effects between two types of agents emerge agents with temptation prefer a lower garnishment rate as tighter borrowing constraint prevents them from over borrowing while those without prefer better consumption smoothing enabled by a higher garnishment rate

vertically differentiated simultaneous vickrey auctions theory and experimental evidence we study settings where a number of sellers simultaneously offer vertically differentiated vickrey auctions for imperfect substitute goods to unit demand buyers vertical differentiation can arise from differences in item quality item value certainty seller reliability or a combination of these factors we characterize the form of the bidding equilibria and derive expressions for the corresponding allocative efficiency and expected seller revenue when bidders are restricted to submit at most one bid our theory predicts the existence of a unique bayes nash equilibrium that resembles a form of probabilistic mating of likes allowing unit demand bidders to place an arbitrary number of bids induces complex strategy profiles where bidders place positive bids in all available auctions higher bidder types tend to follow more targeted strategies focusing their serious bids on fewer and generally higher quality auctions the nature of the bidding equilibria introduces allocative inefficiencies that arise from the lack of coordination in auction selection among bidders we test our theoretical propositions in a controlled laboratory experiment while also utilizing a domain specific risk score to help assess how the bidders risk type affects their bidding behavior in support of our theory we find evidence of a probabilistic assortative matching between bidder and auction types we also find that low risk type bidders tend to crowd on the highest auction and will pay a premium for the certainty it offers whereas high risk type bidders fail to appropriately adjust for risk associated with the lowest auction leading to overbidding these lead to an interesting focal anomaly whereby bids are concentrated on the highest and lowest auctions bypassing intermediate auctions

temptation and taxation we study optimal taxation when consumers have temptation and self control problems embedding the class of preferences developed by gul and pesendorfer into a standard macroeconomic setting we first prove in a two period model that the optimal policy is to subsidize savings when consumers are tempted by excessive impatience the savings subsidy improves welfare because it makes succumbing to temptation less attractive we then study an economy with a long but finite horizon which nests as a special case the phelps pollak laibson multiple selves model thereby providing guidance on how to evaluate welfare in this model we prove that when period utility is logarithmic the optimal savings subsidies increase over time for any finite horizon moreover as the horizon grows large the optimal policy prescribes a constant subsidy in contrast to the well known chamley judd result

dividing online and offline a case study every new method of trade offers an opportunity for economic agents to compare its costs and benefits relative to the status quo such comparison motivates sorting across market segments and reshapes the whole marketplace the internet provides an excellent example it introduces substantial search cost savings over brick and mortar retail stores but imposes new obstacles for sellers to convey quality using sports card trading as a case study we provide empirical evidence on 1 the sorting of product quality between the online and offline segments 2 the changes for retail outlets after the internet came into place and 3 how supporting industries such as professional grading and card manufacturing adapted to take advantage of the new market copyright 2007 wiley blackwell

is being flexible advantageous for demands this paper analyzes the impacts of flexible demands on day ahead market outcomes in a system with significant wind power production we use a two stage stochastic market clearing model where the first stage represents the day ahead market and the second stage represents the real time operation on one hand flexibility of demands is beneficial to the system as a whole since such flexibility reduces the operation cost but on the other hand shifts in demands from peak periods to off peak periods may influence prices in such a way that demands may not be willing to provide flexibility specifically we investigate the impacts of different degree of demand flexibility on day ahead prices a number of scenarios modeling the uncertainty associated with wind production at the operation stage and nonconvexities due to start up costs of generators and their minimum power outputs are taken into account

accounting for the u s earnings and wealth inequality we show that a theory of earnings and wealth inequality based on the optimal choices of ex ante identical households that face uninsured idiosyncratic shocks to their endowments of efficiency labor units accounts for the u s earnings and wealth inequality almost exactly

5 information impact and allocation rules in auctions with affiliated private values a laboratory study in affiliated private value auctions each bidder has perfect information regarding his her own value for the object at auction but higher values of the item for one bidder make higher values for other bidders more likely we report on a series of experiments examining three key implications of these auctions i in a first price auction public information about rivals values increases expected revenue ii an english auction increases expected revenue compared to a first price auction and iii a second price auction is isomorphic to an english auction in examining these issues we compare predictions of some ad hoc bidding models with nash equilibrium predictions in the first price auction experiments nash equilibrium bidding theory organizes the data better than either of two ad hoc bidding models public information about others valuations does increase average revenue but the increase in revenue is smaller and less reliable than predicted under risk neutral nash equilibrium bidding lower average revenue might be attributed to risk aversion while the high variability is attributed to a sizable frequency of individual bidding errors relative to the theory bidding theory precisely organizes english auction outcomes after a brief initial learning period the dominant strategy equilibrium does not organize second price auctions nearly as well as market prices persistently exceed predicted prices the difference between english and second price outcomes is attributed to effects of different information flows inherent in the structure of the two institutions on eliminating bidding errors revenue impacts of these two institutions relative to a first price auction are examined in light of observed bidding patterns

do auctioneers pick optimal reserve prices we investigate how auctioneers set reserve prices in auctions a well established theoretical result assuming risk neutrality of the seller is that the optimal reserve price should not depend on the number of participating bidders in a set of controlled laboratory experiments we find that seller behavior often deviates from the theoretical benchmarks we extend the existing theory to explore three alternative explanations for our results risk aversion anticipated regret and probability weighting after fitting our data to each of these models through parameter estimation techniques on both an aggregate and individual level we find that all three models are consistent with some of the characteristics of our data but that the regret model provides a slightly more favorable fit overall this paper was accepted by teck hua ho decision analysis

business to business electronic commerce just as the industrial revolution mechanized the manufacturing functions of firms the information revolution is automating their merchant functions four types of potential productivity gains are expected from business to business b2b electronic commerce cost efficiencies from automation of transactions potential advantages of new market intermediaries consolidation of demand and supply through organized exchanges and changes in the extent of vertical integration of firms the article examines the characteristics of b2b online intermediaries including categories of goods traded market mechanisms employed and ownership arrangements and considers the market structure of b2b e commerce

mechanism design by competing sellers a dynamic model with many sellers and buyers is constructed agents failing to trade may trade in the next period an equilibrium is found where sellers hold identical auctions and buyers randomize over the sellers they visit the distribution of buyer valuations is endogenous an auction with efficient reserve is an optimal mechanism from each seller s point of view in spite of the ability of any seller to alter the distribution of buyer types participating in the seller s mechanism by altering the mechanism copyright 1993 by the econometric society

cross bidding impact throughout the product life cycle abstract two products at different points of the product life cycle have been chosen to analyse the effect of cross bidding in competing auctions the findings indicate that this strategy can have a different impact depending on the phase of the cycle

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

procrastination and obedience in this lecture i shall focus on situations involving repeated decisions with time inconsistent behavior although each choice may be close to maximizing and therefore result in only small losses the cumulative effect of a series of repeated errors may be quite large thus in my examples decision makers are quite close to the intelligent well informed individuals usually assumed in economic analysis but cumulatively they make seriously wrong decisions that do not occur in standard textbook economics this lecture discusses and illustrates several pathological modes of individual and group behavior procrastination in decision making undue obedience to authority membership of seemingly normal individuals in deviant cult groups and escalation of commitment to courses of action that are clearly unwise in each case individuals choose a series of current actions without fully appreciating how those actions will affect future perceptions and behavior the standard assumption of rational forwardlooking utility maximizing is violated the nonindependence of errors in decision making in the series of decisions can be explained with the concept from cognitive psychology of undue salience or vividness for example present benefits and costs may have undue salience relative to future costs

price quality and reputation evidence from an online field experiment we examine the link between price quality seller claims and seller reputation in internet auctions after purchasing actual baseball cards and having them professionally graded we find that some buyers in the online graded market are misled by incredible claims of quality they pay higher prices but do not receive better quality and in fact are defrauded more often online seller reputation is effective for identifying good faith sellers but conditional on completed auctions reputable sellers do not provide better quality evidence also suggests that high claim sellers target less experienced buyers we attribute these patterns to two loopholes in the ebay rating system we benefited from the comments of austan goolsbee raphael thomadsen john shea dan vincent david reiley larry ausubel peter cramton v joseph hotz jeff smith jimmy chan vincent crawford mark duggan and attendees at numerous seminars and conferences we are particularly grateful to seth sanders and john list for their constructive advice at the early stage of the research to timothy bresnahan rachel kranton and thomas hubbard for their detailed suggestions in reshaping earlier versions and to editor ariel pakes and two anonymous referees for their careful readings special thanks to eight friends who acted as our agents in purchasing baseball cards in retail markets and to numerous sports card store owners who shared their insights on the sportscard industry excellent research assistance from randy alexander moore and krzysztof fizyta is gratefully acknowledged any remaining errors are ours

internet auctions with many traders abstract we study a multi unit auction environment similar to ebay sellers each with a single unit of a homogeneous good set reserve prices at their own second price auctions each buyer has private value for the good and wishes to acquire a single unit buyers can bid as often as they like and move between auctions we characterize a perfect bayesian equilibrium for this decentralized dynamic mechanism in which conditional on reserve prices an efficient set of trades occurs at a uniform price in a large but finite market the sellers set reserve prices equal to their true costs under a very mild distributional assumption so ex post efficiency is achieved buyers strategies in this equilibrium are simple and do not depend on their beliefs about other buyers valuations or the number of buyers and sellers

borrowing costs and the demand for equity over the life cycle abstract we construct a life cycle model that delivers realistic behavior for both equity holdings and borrowing the key model ingredient is a wedge between the cost of borrowing and the risk free investment return borrowing can either raise or lower equity demand depending on the cost of borrowing a borrowing rate equal to the expected return on equity which we show roughly matches the data minimizes the demand for equity alternative models with no borrowing or limited borrowing at the risk free rate cannot simultaneously fit empirical evidence on borrowing and equity holdings

endogenous political turnover and fluctuations in sovereign default risk abstract a sovereign default model in which the sovereign derives private benefits from public office and contests elections to stay in power is developed the economy s growth process is modeled as a markov switching regime which is shown to be a better description of the data for our set of emerging economies in the model consistent with evidence the sovereign is less likely to be reelected if economic growth is weak in the low growth regime there is higher probability of loss of private benefits due to turnover which makes the sovereign behave more myopically this growth linked variation in effective discount factor is shown to be important in generating volatility in sovereign spreads

pennies from ebay the determinants of price in online auctions this paper presents an exploratory analysis of the determinants of prices in online auctions for collectible united states one cent coins at the ebay web site starting with an initial data set of 20 000 auctions we perform regression analysis on a restricted sample of 461 coins for which we obtained estimates of book value we have three major findings first a seller s feedback ratings reported by other ebay users have a measurable effect on her auction prices negative feedback ratings have a much greater effect than positive feedback ratings do second minimum bids and reserve prices have positive effects on the final auction price in particular minimum bids appear only to have a significant effect when they are binding on a single bidder as predicted by theory third when a seller chooses to have her auction last for a longer period of days this significantly increases the auction price on average

income and wealth heterogeneity in the macroeconomy how do movements in the distribution of income and wealth affect the macroeconomy we analyze this question using a calibrated version of the stochastic growth model with partially uninsurable idiosyncratic risk and movements in aggregate productivity our main finding is that in the stationary stochastic equilibrium the behavior of the macroeconomic aggregates can be almost perfectly described using only the mean of the wealth distribution this result is robust to substantial changes in both parameter values and model specification our benchmark model whose only difference from the representative agent framework is the existence of uninsurable idiosyncratic risk displays far less cross sectional dispersion and skewness in wealth than u s data however an extension that relies on a small amount of heterogeneity in thrift does succeed in replicating the key features of the wealth data furthermore this extension features aggregate time series that depart significantly from permanent income behavior

prospect theory in a dynamic game theory and evidence from online pay per bid auctions abundant evidence exists that expected utility theory does not adequately describe decision making under risk although prospect theory is a popular alternative it is rarely applied in strategic situations in which risk arises through individual interactions this study fills this research gap by incorporating prospect theory preferences into a dynamic game theoretic model using a large field data set from multiple online pay per bid auction sites the authors empirically show that their proposed model with prospect theory preferences makes a better out of sample prediction than a corresponding expected utility model prospect theory also provides a unified explanation for two behavioral anomalies average auctioneer revenues above current retail prices and the sunk cost fallacy the empirical results indicate that bidders are loss averse and overweight small probabilities such that the expected revenue of the auction exceeds the current retail price by 25 46 the authors illustrate and empirically confirm a managerial implication for how an auctioneer can increase revenue by changing the details of the auction design

macroeconomic effects of bankruptcy and foreclosure policies i study the implications of two major debt relief policies in the united states the bankruptcy abuse prevention and consumer protection act bapcpa and the home affordable refinance program harp

the dynamics of seller reputation evidence from ebay we construct a panel of ebay seller histories and examine the importance of ebay s reputation mechanism we find that when a seller first receives negative feedback his weekly sales rate drops from a positive 7 to a negative 7 subsequent negative feedback ratings arrive 25 more rapidly than the first one and don t have nearly as much impact as the first one we also find that a seller is more likely to exit the lower his reputation is and that just before exiting sellers receive more negative feedback than their lifetime average we consider a series of theoretical models and measure them against these empirical results regardless of which theoretical model best explains the data an important conclusion of our paper is that ebay s reputation system gives way to noticeable strategic responses from both buyers and sellers

competition among sellers who offer auctions instead of prices abstract in this paper we study a large market in which sellers compete by offering auctions to buyers instead of simple fixed price contracts two variants of the model are studied one extends a model first analyzed by wolinsky rev econ stud 55 1988 71 84 in which buyers learn their valuations only after meeting sellers the other variant extends the model of mcafee econometrica61 1993 1281 1312 in which buyers know their valuations before they choose among available auctions the equilibrium array of auctions is characterized for each case and the efficiency properties of the equilibria are analyzed journal of economic literatureclassification numbers d41 d44 d82

an empirical investigation of efficiency and price uniformity in competing auctions abstract in undetermined this paper investigates hypotheses related to efficiency and price uniformity in online competing auctions based on two theoretical predictions from peters and severinov peters m severinov s 2006 internet auctions with many traders journal of economic theory 130 220 245 the investigation is conducted using a large and ideal data set for online competing train ticket auctions and the findings support the theoretical predictions in large parts

pricing electricity in pools with wind producers this paper considers an electricity pool that includes a significant number of wind producers and is cleared through a network constrained auction one day in advance and on an hourly basis the hourly auction is formulated as a two stage stochastic programming problem where the first stage represents the clearing of the market and the second stage models the system operation under a number of plausible wind production realizations this formulation co optimizes energy and reserve and allows deriving both pool energy prices and balancing energy prices these prices result in both cost recovery for producers and revenue reconciliation a case study of realistic size is used to illustrate the functioning of the proposed pricing scheme

household borrowing after personal bankruptcy a large body of literature has examined factors leading to filing for personal bankruptcy but little is known about household borrowing after bankruptcy this paper augments the existing literature with a comprehensive analysis of postbankruptcy borrowing using data from the survey of consumer finances we find that filers generally have more limited access to unsecured credit but borrow more secured debt after bankruptcy than comparable households that have never filed for bankruptcy filers also pay higher interest rates on all types of debt in addition as more time passes after filing credit access and borrowing costs improve however filers remain more prone than comparable nonfilers to experience financial distress accumulate less wealth and use expensive credit sources like payday loans even more than 10 years after filing

bidding behavior in competing auctions evidence from ebay much of the existing auction literature treats auctions as running independently of one another with each bidder choosing to participate in only one auction however in many online auctions a number of substitutable goods are auctioned concurrently and bidders can bid on several auctions at the same time recent theoretical research shows how bidders can gain from the existence of competing auctions the current paper providing the first empirical evidence in support of competing auctions theory using online auctions data from ebay our results indicate that a significant proportion of bidders do bid across competing auctions and that bidders tend to submit bids on auctions with the lowest standing bid as the theory predicts the paper also shows that winning bidders who cross bid pay lower prices on average than winning bidders who do not

choice and procrastination author s o donoghue ted rabin matthew abstract recent models of procrastination due to self control problems assume that a procrastinator considers just one option and is unaware of her self control problems we develop a model where a person chooses from a menu of options and is partially aware of her self control problems this menu model replicates earlier results and generates new ones a person might forego completing an attractive option because she plans to complete a more attractive but never to be completed option hence providing a non procrastinator additional options can induce procrastination and a person may procrastinate worse pursuing important goals than unimportant ones

consumption over the life cycle facts from consumer expenditure survey data this paper uses consumer expenditure survey data and a seminonparametric statistical model to estimate life cycle profiles of consumption controlling for demographics cohort and time effects we construct age profiles for total and nondurable consumption as well as expenditure patterns for consumer durables special emphasis is placed on the comparison of different approaches to control for changes in demo graphics over the life cycle we find significant humps over the life cycle for total nondurable and durable expenditures changes in household size account for roughly half of these humps bootstrap simulations suggest that our empirical estimates are tight in that standard errors are small

search costs and equilibrium price dispersion in auction markets abstract a leading explanation for price dispersion in posted price markets is search costs we incorporate this insight into a model of competing second price auctions similar to ebay by doing so we extend the narrow literature on competing auctions to capture price dispersion and grow the already large literature on price dispersion to include auctions we provide evidence on search costs and price dispersion using data collected from ebay identifying search costs by exploiting a discontinuity in the visibility of auctions due to ebay s search tool

economic valuation of reserves in power systems with high penetration of wind power this paper proposes a methodology to determine the required level of spinning and nonspinning reserves in a power system with a high penetration of wind power the computation of the required reserve levels and their costs is achieved through a stochastic programming market clearing model spanning a daily time horizon this model considers the network constraints and takes into account the cost of both the load shedding and the wind spillage the methodology proposed is illustrated using an example and a realistic case study some conclusions are finally drawn

on absolute auctions and secret reserve prices from a theory viewpoint the use of auctions with zero public reserve prices also called absolute auctions or of auctions with secret reserve prices is somewhat puzzling despite being common by allowing that buyers differ in their processing of past data regarding how the participation rate varies with the auction format and how reserve prices are distributed when secret we show in a competitive environment that these auction formats may endogenously emerge we also analyze how buyers with various sophistications and sellers with various costs sort into the different formats thereby offering a range of testable predictions alternative approaches are reviewed

self control and the theory of consumption to study the behavior of agents who are susceptible to temptation in infinite horizon consumption problems under uncertainty we define and characterize dynamic self control dsc preferences dsc preferences are recursive and separable in economies with dsc agents equilibria exist but may be inefficient in such equilibria steady state consumption is independent of initial endowments and increases in self control increasing the preference for commitment while keeping self control constant increases the equity premium removing nonbinding constraints changes equilibrium allocations and prices debt contracts can be sustained even if the only feasible punishment for default is the termination of the contract

collusion and the choice of auction auctions are used in many different markets including the leasing of a substantial fraction of the natural resources in the united states the procedures used in the auctions conducted by the federal government have been a continuing source of controversy one of the concerns has been the possibility of collusion among bidders this article shows that cartels are stable if the seller uses open ascending bid oral auctions but not if he uses sealed high bid auctions this may help to explain the frequent use of sealed high bid auctions

ramsey meets laibson in the neoclassical growth model the neoclassical growth model is modified to include a variable rate of time preference with no commitment ability and log utility the equilibrium features a constant effective rate of time preference and is observationally equivalent to the standard model the extended framework yields testable linkages between the extent of commitment ability and the rates of saving and growth the model also has welfare implications including the optimal design of institutions that facilitate household commitments steady state results are obtained for general concave utility functions and some properties of the transitional dynamics are characterized for isoelastic utility

consumption and risk sharing over the life cycle a striking feature of u s data on income and consumption is that inequality increases with age this paper asks if individual specific earnings risk can provide a coherent explanation we find that it can we construct an overlapping generations general equilibrium model in which households face uninsurable earnings shocks over the course of their lifetimes earnings inequality is exogenous and is calibrated to match data from the u s panel study on income dynamics consumption inequality is endogenous and matches well data from the u s consumer expenditure survey the total risk households face is decomposed into that realized before entering the labor market and that realized throughout the working years in welfare terms the latter is found to be more important than the former

identification of standard auction models this paper presents new identification results for models of first price second price ascending english and descending dutch auctions we consider a general specification of the latent demand and information structure nesting both private values and common values models and allowing correlated types as well as ex ante asymmetry we address identification of a series of nested models and derive testable restrictions enabling discrimination between models on the basis of observed data the simplest model symmetric independent private values is nonparametrically identified even if only the transaction price from each auction is observed for richer models identification and testable restrictions may be obtained when additional information of one or more of the following types is available i the identity of the winning bidder or other bidders ii one or more bids in addition to the transaction price iii exogenous variation in the number of bidders iv bidder specific covariates while many private values pv models are nonparametrically identified and testable with commonly available data identification of common values cv models requires stringent assumptions nonetheless the pv model can be tested against the cv alternative even when neither model is identified

u s consumer bankruptcy choice the importance of general equilibrium effects abstract we study the implications of u s personal bankruptcy rules for resource allocation and welfare our analysis shows that general equilibrium considerations along with bankruptcy chapter choice and production matter crucially for the effects of policy reform contrary to previous work we find that completely eliminating bankruptcy provisions causes significant declines in output and welfare by reducing capital formation and labor input furthermore subjecting chapter 7 filers to means testing as suggested by recent legislative proposals would not improve upon current bankruptcy provisions and at best leave aggregate filings output and welfare unchanged however we do find that an alternative tightening of chapter 7 in the form of lower asset exemptions can increase economic efficiency

using elasticities to derive optimal bankruptcy exemptions this article studies the optimal determination of bankruptcy exemptions for risk averse borrowers who use unsecured contracts but have the possibility of defaulting in a large class of economies knowledge of four variables is sufficient to determine whether a bankruptcy exemption level is optimal or should be increased or decreased these variables are 1 the composition of households liabilities 2 the sensitivity of the credit supply schedule to exemption changes 3 the probability of filing for bankruptcy with non exempt assets and 4 the value given by households to a marginal dollar in different states which can be mapped to changes in households consumption i recover empirical estimates of the sufficient statistics using u s data over the period 2008 16 and find that increasing exemption levels improves overall welfare although there is substantial variation in estimated welfare gains across u s states and income quintiles

reputation in an internet auction market i introduction without transmission of credible information asymmetries may lead to underproduction of goods or even market failure reputation mitigates inefficiencies associated with information asymmetries by providing an informative signal of quality 1 the difficulty in quantifying reputation means that few studies can analyze empirically the role of reputation in markets our analysis of a quantified market observed measure of reputation provides direct evidence of the effect of a seller s reputation on the terms of a onetime real world transaction thereby contributing empirical support to a fundamental economic principle this study empirically examines person to person transactions within the internet market known as ebay in this virtual market of unseen participants and products buyers and sellers face the risks of repudiation as the counter party may deny the agreement after the fact buyers assume risks associated with lack of seller integrity and asymmetric information about the particular product as the buyer is typically required to send payment before the seller ships the product in addition for many ebay transactions the cost of enforcing a contract is high relative to the transaction s value resulting in a practical absence of legal enforcement 2 by providing a history of trade execution information ebay benefits market participants by reducing information asymmetries while achieving substantial transaction cost economies market participants relate personal experiences which ebay uses to calculate a numerical reputation measure for each user market participants in turn can use this reputation measure to assess counter party risk and adjust bidding behavior accordingly in a sample of 460 auctions held between january 1998 and july 1998 we find a positive relation between prices and ebay s reputation measure higher reputation sellers experience higher auction prices ceteris paribus our findings suggest that repeat players are rewarded for building reputation consistent with the belief that the high reputation seller s value of future transactions outweighs the value of taking advantage of the buyer in the current transaction buyers are willing to pay more to a higher reputation seller this article contributes to the literature not only by providing quantitative support of long accepted reputation theories but also by illustrating the use of nontraditional markets as a natural laboratory for experiments this article is an example of how a newly formed electronic market can provide the elements necessary for analytical research we find that ebay transactions for this item exhibit characteristics similar to transactions in more conventional markets namely 1 prices are higher when there is less quantity supplied when fewer of the items are available the same day 2 prices are lower during periods of lower demand times less likely to have high traffic 3 sellers with higher shipping and handling costs receive lower prices and 4 sellers failing to provide information about shipping and handling fees i e larger information asymmetries receive fewer bids dramatic innovations in online market structure and increasing availability of online market data should enable researchers to examine directly other traditionally non quantifiable economic ideas this article is organized as follows section ii describes how reputation can be used to facilitate transactions in the presence of asymmetric information section iii describes the ebay market summarizes the listing and bidding processes and discusses the reputation mechanism for this market section iv presents the price and reputation descriptive statistics associated with a consistently auctioned item and reports the empirical findings of how this item s highest bid price varies with the level of the seller s reputation we conclude in section v with a discussion of ebay s continued attempts to add value to the market through recent structural changes

search and choice in online consumer auctions price dispersion in simultaneous online auctions is a puzzle in light of the relatively low search costs required to find the lower price much of this price dispersion appears to be due to a lack of switching by bidders between auctions which in turn could be due to inertia related to search costs we identify some of the influencing factors through a controlled field experiment involving pairs of simultaneous auctions keeping the sellers and the goods sold identical between two auctions we vary auction design features between and within pairs including shipping cost open reserve secret reserve price and duration and we provide bidders with incentives to search we use a choice model that examines individual choice between pairs of simultaneous auctions we find that within pair price dispersion is substantial and that prices and auction choice by bidders are indeed related to search costs we find strong inertia in auction choice and find that this effect significantly interacts with time left in the auction although individuals do not always choose a lower priced auction they are more likely to do so when search costs are low or search incentives are high

hyperbolic discounting and uniform savings floors abstract previous research suggests that in partial equilibrium individuals whose decision making exhibits a present bias such as hyperbolic discounters who tend to over consume will be in favor of having a floor imposed on their savings in this paper i show it is quite difficult for the introduction of a savings floor to be pareto improving in general equilibrium indeed a necessary condition for the floor to be pareto improving is that it is high enough to be binding for all individuals even in that case because the equilibrium interest rate adjusts with the level of the savings floor some individuals may prefer to commit to a future time path of consumption by facing a high interest rate and no floor rather than a high floor an essential insight for understanding this result is to note that even those with little self control in an absolute sense will choose to save a lot when the interest rate is high enough

estimation of beauty contest auctions beauty contests are auction mechanisms used to buy or sell differentiated products where the auctioneer does not specify a decision rule to pick the winning bidder beauty contests are widely used in procuring welfare to work projects freelance services selling online ads real estate transactions and hiring dating marriage decisions unlike price only auctions beauty contests have no closed form bidding strategies and suffer from nonmultiplicatively separable unobserved auction heterogeneity which makes their estimation challenging to address these challenges we formulate beauty contests as incomplete information games and present a two step estimator a key contribution of our method is its ability to account for common knowledge auction specific unobservables using finite unobserved types we show that unobserved auction types and distributions of bids are nonparametrically identified and recoverable in the first step using a nonparametric expectation maximization em like algorithm and that

a robust optimization approach to energy and reserve dispatch in electricity markets abstract to a large extent electricity markets worldwide still rely on deterministic procedures for clearing energy and reserve auctions however increasing shares of the production mix consist of renewable sources whose nature is stochastic and non dispatchable as their output is uncertain and cannot be controlled by the operators of the production units stochastic programming models allow the joint determination of the day ahead energy and reserve dispatch accounting for the uncertainty in the output from these sources however the size of these models gets quickly out of hand as a large number of scenarios are needed to properly represent the uncertainty in this work we take an alternative approach and cast the problem as an adaptive robust optimization problem the resulting day ahead energy and reserve schedules yield the minimum system cost accounting for the cost of the redispatch decisions at the balancing real time stage in the worst case realization of the stochastic production within a specified uncertainty set we propose a novel reformulation of the problem that allows considering general polyhedral uncertainty sets in a case study we show that in comparison to a risk averse stochastic programming model the robust optimization approach progressively trades off optimality in expectation with improved performance in terms of risk these differences however gradually taper off as the level of risk aversion increases for the stochastic programming approach computational studies show that the robust optimization model scales well with the size of the power system which is promising in view of real world applications of this approach

sealed bid versus open auctions the evidence data from u s forest service timber auctions are used to test vickrey s original proposition that sealed bid and open auctions yield equal revenue models for the high bid in an auction are specified and estimated using three different procedures ordinary least squares two stage least squares and maximum likelihood the second two procedures include a second equation which accounts for the forest service s auction choice and therefore control for selection bias these two procedures which unlike ordinary least squares yield consistent estimators imply a statistically and economically insignificant difference in high bids between sealed bid and open auctions

hedonic prices and implicit markets estimating demand and supply functions for differentiated products in choosing the level of quality to purchase the buyer of a differentiated product also chooses a point on the marginal price schedule for that product hence in general the demand functions for product characteristics cannot be consistently estimated by ordinary least squares market equilibrium results in a matching of characteristics of demanders and suppliers this matching restricts the use of buyer and seller characteristics as instruments when estimating demand and supply functions for product characteristics the paper develops these issues a stochastic structure for hedonic equilibrium models is then proposed identification results are presented and estimation procedures are outlined

bidding off the wall why reserve prices may be kept secret abstract this note shows by means of an example that in a common value auction a seller with a random reservation value can increase her ex ante expected profits by following a policy of conducting an auction in which her reserve price is kept secret compared to an auction in which the reserve price is announced by keeping the reserve price secret the seller is able to encourage greater participation from the bidders and can therefore increase the linkage of the price paid to the value of the purchased object journal of economic literature classification numbers d82 d44

vickrey auctions in practice from nineteenth century philately to twenty first century e commerce william vickrey 1961 proposed an auction mechanism in which bidders submit sealed bids and the highest bidder wins the good in return for payment of the second highest bid amount for decades economists have credited vickrey with inventing this auction format and have believed that the vickrey auction is rarely used in practice this paper presents evidence that vickrey auctions have long been the predominant auction format for mail sales of collectible postage stamps stamp auctioneers developed this auction format on their own as early as 1893 even before vickrey was born

the winner s curse reserve prices and endogenous entry empirical insights from ebay auctions internet auctions have recently gained widespread popularity and are one of the most successful forms of electronic commerce we examine a unique data set of ebay coin auctions to explore the determinants of bidder and seller behavior we begin by documenting a number of empirical regularities in our data set of ebay auctions next we specify and estimate a structural econometric model of bidding on ebay using our parameter estimates from this model we measure the extent of the winner s curse and simulate seller revenue under different reserve prices