planning under incomplete information and the ratchet effect abstract central planning of production is usually performed under asymmetric information the firm in general has more information about its productive possibilities than the central planner from now on for short cp this justifies the use of incentives schemes in which the cp does not directly fix activity levels casual observation of such existing schemes suggests that the time dimensions is crucial for their working typically the cp revises the incentive scheme over time to take into account the information provided by the firm s performance managers of centrally planned economies as well as economists have long recognized that this revision induces firms to underproduce in order to avoid demanding schemes in the future this is the ratchet effect it is purpose of the present paper to study the ratchet effect under the non commitment assumption which we believe to be more realistic the inadequacy of conceptual tools made if difficult in the past to consider such an assumption now basic research on dynamic games with incomplete information recently resulted in new ideas which look particularly relevant for a theoretical analysis of the problem

bargaining over reform abstract this paper models the delay in a macroeconomic stabilization as the outcome of a bargaining game between two parties who must reach an agreement over how the stabilization cost is to be shared the paper modifies alesina and drazen s 1991 american economic review 81 1170 1189 war of attrition model by endogenizing the distribution of the stabilization costs through a bargaining game using this bargaining framework the paper analyzes the role of crises and foreign assistance in bringing about a settlement to the distributional conflict in the bargaining game a crisis that increases the welfare loss from not stabilizing the economy will lower the probability of delay in contrast foreign aid that is used to reduce the stabilization costs will further increase the delay in reaching an agreement between the two parties

limit theorems for markets with sequential bargaining this paper models trade as a non coopertative strategic game played at an inlinite sequence of dates a single indivisible commodity is traded buyers and sellers have transferable utility and are characterized by their reservation utilities they meet at random and bargain over the price at which a single unit of the good will be exchanged under a variety of circumstances it is shown that as the costs of search and bargaining become negligible the outcome of the game converges to the competitve flow equilibrium even when there is complete information journal of economic literature classification numbers 022 19x7

decentralized trading strategic behaviour and the walrasian outcome for a market with a finite number of agents pairwise matching and bargaining it is shown that even when the market is frictionless the equilibrium is not necessarily competitive it depends on the amount of information agents use if their behaviour is conditioned only on the sets of agents present and the time the competitive solution is the unique subgame perfect equilibrium if agents have full information and condition their behaviour on some of it there are also noncompetitive equilibria in which behaviour depends on specific information such as the identity of the trading partner and past events

the demand for imf credits by sub saharan african countries abstract in this paper the demand behaviour of sub saharan african countries for imf credits will be studied on the basis of pooled cross section and time series analysis it will be concluded that drawings on imf facilities are not a purely economic phenomenon

does conditionality work a test for an innovative us aid scheme performance based aid has been proposed as an alternative to the failed traditional approach whereby donors make aid conditional on the reform promises of recipient countries however hardly any empirical evidence exists on whether ex post rewards are effective in inducing reforms we attempt to fill this gap by investigating whether the millennium challenge corporation mcc was successful in promoting better control of corruption we employ a difference in difference in differences ddd approach considering different ways of defining the treatment group as well as different time periods during which incentive effects could have materialized we find evidence of strong anticipation effects immediately after the announcement of the mcc while increasing uncertainty about the timing and amount of mcc aid appears to have weakened the incentive to fight corruption over time

regulating prostitution a health risk approach abstract we build an equilibrium model of prostitution where clients and sex workers choose to demand and supply sex under three legal regimes prohibition regulation and laissez faire the key feature is the endogenous evolution of the risk as a consequence of policy changes we calibrate the model to empirical evidence from italy and then compare the effect of different policies on the equilibrium quantity of prostitution and on the harm associated with it a prohibition regime that makes it illegal to buy sex but not to sell it is more effective than the opposite regime in reducing quantity taxes are one inducement to go illegal and prevent some of the less risky individuals from joining the market leaving it smaller but riskier a licensing system that prevents some infected individuals from joining the legal market reduces the risk and is therefore associated with an increase in quantity prohibition is preferable to minimize quantity only if a high expected fine is feasible regulation is best to minimize harm

health risky behaviour and the value of medical innovation for infectious disease we propose a dynamic framework to study the value of medical innovation in the context of infectious disease we apply our framework to evaluate an hiv treatment breakthrough known as haart the model captures how in lowering both the expected cost and likelihood of hiv infection haart reduced the implicit price of risky sex forward looking agents responded by optimally shifting their behaviour the model also imposes equilibrium constraints explicitly capturing how optimal shifts in behaviour affect equilibrium choices by changing both infection probabilities and the ease of finding partners willing to engage in risky sex using the estimated model we conduct counterfactual simulations to compute the value of haart from the perspective of uninfected agents this includes the option value of the innovation along with value accruing from changes in sex behaviour in response to haart introduction we also calculate the added value of a fully functional vaccine from the perspective of both infected and uninfected agents where infected agents benefit from a vaccine due to resulting shifts in market equilibrium

integrating behavioral choice into epidemiological models of aids increased hiv risk creates incentives for people with low sexual activity to reduce their activity but may make high activity people fatalistic leading them to reduce their activity only slightly or actually increase it if high activity people reduce their activity by a smaller proportion than low activity people the composition of the pool of available partners will worsen creating positive feedbacks and possibly multiple steady states early public health efforts may allow societies to reach more favorable steady states excerpt

foreign aid and market liberalizing reform market oriented economic policies reflected in limited economic activity by government protection of private property rights sound monetary policy outward orientation regarding trade and efficient tax and regulatory policy have been strongly linked to faster rates of economic growth foreign aid is often provided in the belief that it encourages liberalizing reforms in these areas this paper analyzes the impact of aid on market liberalizing policy reform correcting for the possible endogeneity of aid results indicate that higher aid slowed reform over the 1980 2000 period as measured by a broad index of policies disaggregating policy into five areas aid is significantly linked to slower reform in some policy areas but not in others disaggregating by decade aid s adverse impact on policy reform is much more pronounced for the 1980s than for the 1990s

risk and rationalization the role of affect and cognitive dissonance for sexual risk taking this paper analyzes the mechanisms underlying excessive sexual risk taking in the presence of hiv drawing ideas from psychology on decision making processes and risk evaluation a theoretical mode

market oriented institutions and policies and economic growth a critical survey this paper surveys recent evidence suggesting that market oriented institutions and policies are strongly related to economic growth focusing on studies using the economic freedom ef indicator of the fraser institute this index is critically discussed also various serious shortcomings of empirical studies using this index are identified nevertheless there are strong indications that liberalization i e an increase in the ef index stimulates economic growth this paper also reviews studies on the determinants of ef political liberalization is often found to enhance economic liberalization whereas there is less evidence for causality running in the other direction

why do mothers breastfeed girls less than boys evidence and implications for child health in india breastfeeding is negatively correlated with future fertility because nursing temporarily reduces fecundity and because mothers usually wean on becoming pregnant again we model breastfeeding under son biased fertility preferences and show that breastfeeding duration increases with birth order especially near target family size is lowest for daughters and children without older brothers because their parents try again for a son and exhibits the largest gender gap near target family size when gender is most predictive of subsequent fertility data from india confirm each prediction moreover child survival exhibits similar patterns especially in settings where the alternatives to breastmilk are unsanitary

risky sex in a risky world sexual behavior in a hiv aids environment in spite of increased awareness of hiv aids unprotected casual sex is still widespread in many hiv infected countries in this paper a two period model for sexual decisions under uncertainty is d

correlated equilibrium as an expression of bayesian rationality if it is common knowledge that the players in a game are bayesian utility maximizers who treat uncertainty about other players actions like any other uncertainty then the outcome is necessarily a correlated equilibrium random strategies appear as an expression of each player s uncertainty about what the others will do not as the result of willful randomization use is made of the common prior assumption according to which differences in probability assessments by different individuals are due to the different information that they have where information may be interpreted broadly to include experience upbringing and genetic makeup copyright 1987 by the econometric society

eliciting and utilizing willingness to pay evidence from field trials in northern ghana we utilize the becker degroot marschak 1964 mechanism to estimate the willingness to pay for clean drinking water technology in northern ghana the bdm mechanism has attractive properties for empirical research allowing us to directly estimate demand compute heterogeneous treatment effects and study the screening and causal effects of prices with minor modifications to a standard field experiment setting we demonstrate the implementation of bdm along these three dimensions compare it to the standard take it or leave it method for eliciting willingness to pay and discuss practical issues for implementing the mechanism in true field settings jel classifications c93 d12 d82 l11 l31

aiding contraception hiv and recent trends in abortion using a difference in differences estimation framework and state level data we investigate the potential role of hiv aids in contributing to declining abortion utilization in the united states our results suggest that the perceived risk of hiv contraction negatively affected unwanted pregnancies specifically a 10 increase in hiv incidence is associated with 0 34 1 1 fewer abortions per live births an effect that can account for at least one tenth of the sharp decline in abortions observed from the early 1980s to mid 1990s

marriage and divorce changes and their driving forces the family is not a static institution in recent decades marriage rates have fallen divorce rates have risen and the defining characteristics of marriage have changed the economic approach to the family seeks to explain these trends by reference to models that can also explain how and why families form gary becker s 1981 treatise on the family proposed a theory based on production complementarities in which husband and wife specialize in the market and domestic spheres respectively production complementarities also arise in the production and rearing of one s own children however production complementarities at least as initially described are decreasingly central to modern family life increased longevity and declining fertility mean that most of one s adult life is spent without one s own children in the household also the rise in marital formation at older ages including remarriage means that many families form with no intention of producing children moreover increases in female labor force participation suggest that household specialization has either declined or at least taken on a different meaning these changes have come about as what is produced in the home has been dramatically altered both by the emergence of labor saving technology in the home and by the development of service industries that allow much of what was once provided by specialized homemakers to be purchased in the market the availabil

one for the road public transportation alcohol consumption and intoxicated driving we exploit arguably exogenous train schedule changes in washington dc to investigate the relationship between public transportation the risky decision to consume alcohol and the criminal decision to engage in alcohol impaired driving using variation over time across days of the week and over the course of the day we provide evidence that overall there was little effect of expanded public transit service on dui arrests alcohol related fatal traffic and alcohol related arrests however we find that these overall effects mask considerable heterogeneity across geographic areas specifically we find that areas where bars are within walking distance to transit stations experience increases in alcohol related arrests and decreases in dui arrests we observe no sign of behavioral changes in neighborhoods without any bars within walking distance of transit stations

understanding economic policy reform one of the eventual consequences of the global debt crisis was a wave of market oriented economic reforms this paper discusses the state of our knowledge on the political economy of this process why were inefficient and often unsustainable policies maintained for so long why are so many governments reforming now after decades of adherence to policies of an opposite kind have the reformers internalized the correct lessons from the east asian experience finally are there any helpful rules for reformers to follow in guiding their policies through complicated political terrain

the long side of the market and the short end of the stick bargaining power and price formation in buyers sellers and balanced markets the determinants of bargaining power and price formation in a dynamic exchange market where new traders enter randomly over time are studied when agents on the long side of the market possess the option to wait for the arrival of future partners the terms of trade in the spot market must honor the value of this option the equilibrium terms of trade are expressed in intuitive closed form equations that highlight the distinct influences of short run spot market conditions and long run market demographics i introduction few concepts in economics are as intuitive as the idea that traders on the long side of a market wind up holding the short end of the stick that is they receive little or none of the gains from trade consider for instance the classic setting in which b identical buyers each with unit demands for an indivisible homogeneous good face s identical sellers each with one unit of the good for sale it is well known that in a broad class of one shot trading games all of the surplus in this setting goes to the short side of the market in equilibrium that is if b s buyers bid the price up to their reservation value often it is only when b s that market institutions the rules of the game have any bearing on the equilibrium division of surplus this classic result is somewhat brittle because of the discontinuity in the terms of trade when moving from positive to negative levels of excess demand its logic is familiar however from bertrand competition and it is very compelling the option value to an agent frozen out of a trade in a one shot market game is his reservation payoff of zero any outcome that confers nonzero surplus to a long side agent cannot be sustained in equilibrium because all of the long side agents who would otherwise be frozen out possess a strict incentive to undercut

imf programs and reforms inhibition or encouragement abstract we analyze the impact of international monetary fund imf programs on market oriented reforms employing panel data for 116 countries over the period 1970 2000 we find that the net effect of imf programs on reforms is negative

one is almost enough for monopoly it has been argued that two factors product durability and potential entry may force a monopolist to price at marginal cost this article shows that when these two forces coexist the tendency toward competition may be negated first we prove that durable goods oligopolists without commitment powers may attain joint profits arbitrarily close to those of a monopolist with perfect commitment power second we demonstrate that the presence of a potential entrant may enable a durable goods monopolist to act as if he had commitment power thus potential as well as actual entry may restore monopoly power

modelling competitive behavior a single seller of an indivisible object wishes to sell the good to one of many buyers the seller has zero value for the good the buyers have a commonly known identical value of one this article attempts to determine strategic environments that ensure the seller s ability to exploit the competitive behavior of the buyers to extract all the surplus in the game i show that in many simple dynamic games there are subgame perfect equilibria that involve the seller s giving up the good for free even if the seller has an informational advantage that allows him to keep bidders from learning the bidding behavior of their opponents there still exist perfect bayesian equilibria that involve a sale at the price of zero however in this case a simple refinement in the spirit of sequential equilibria can be used to rule out such collusive behavior and to show that the unique equilibrium outcome satisfying this refinement yields the seller a price of one

economic activity and the spread of viral diseases evidence from high frequency data viruses are a major threat to human health and given that they spread through social interactions represent a costly externality this article addresses three main questions i what are the unintended consequences of economic activity on the spread of infections ii how efficient are measures that limit interpersonal contacts iii how do we allocate our scarce resources to limit the spread of infections to answer these questions we use novel high frequency data from france on the incidence of a number of viral diseases across space for different age groups over a quarter of a century we use quasi experimental variation to evaluate the importance of policies reducing interpersonal contacts such as school closures or the closure of public transportation networks while these policies significantly reduce disease prevalence we find that they are not cost effective we find that expansions of transportation networks have significant health costs in increasing the spread of viruses and that propagation rates are pro cyclically sensitive to economic conditions and increase with inter regional trade jel codes i12 i15 i18 h51 c23

imf conditionality government partisanship and the progress of economic reforms the international monetary fund imf often seeks to influence countries domestic public policy via varying levels of conditionality linking financial support to borrowing governments commitment to policy reforms when does extensive conditionality encourage domestic economic reforms and when does it impede them we argue that rather than universally benefiting or harming reforms the effects of stricter imf conditionality depend on domestic partisan politics more imf conditions can pressure left wing governments into undertaking more ambitious reforms with little resistance from partisan rivals on the right under right governments however more conditions hinder reform implementation by heightening resistance from the left while simultaneously reducing leaders ability to win their support through concessions or compromise using data on post communist imf programs for the period 1994 2010 we find robust evidence supporting these claims even after addressing the endogeneity of imf programs via instrumental variables analysis

choices beliefs and infectious disease dynamics a dynamic model of risky behavior in the midst of an epidemic is discussed the key result is that pessimistic expectations over the future of the epidemic induce more current risky behavior numerical simulation of equilibrium epidemics shows that this effect can accelerate spread of the disease in an epidemic s early stages and that the effect of policy interventions such as preventative vaccines may depend on whether the intervention was anticipated

noncooperative collusion in durable goods oligopoly coase conjectured that a durable goods monopolist who can make offers to sell arbitrarily frequently will lose the ability to extract positive profits this result which has now been proved can be attributed to the inability of the monopolist to commit to maintaining sufficiently high prices in the near future for the case of durable goods oligopoly we show that letting the firms make offers arbitrarily frequently enhances their ability to commit to high prices and in the limit enables the firms to enjoy total market profits equal to the full commitment one shot monopoly profit

the economic characteristics of imf program countries abstract a logit analysis is utilized to identify the factors that characterized developing nations that entered imf stabilization programs in the early 1980s program countries recorded higher rates of domestic credit growth larger shares of government expenditure more severe current account deficits smaller reserve holdings and lower per capita incomes

hiv breakthroughs and risky sexual behavior recent hiv treatment breakthroughs have lowered hiv mortality in the united states but have also coincided with increased hiv incidence the authors argue that these trends are causally linked because new treatments have improved health and survival for the hiv increased their sexual activity and thus facilitated hiv s spread