economic and other determinants of infant and child mortality in small developing countries the case of central america and the caribbean inter country differences in infant and child mortality are explained by looking at demographic economic health and educational factors a model is presented in which the infant mortality rate the child mortality rate and the birth rate are endogenous the model is tested using cross national multiple regression analysis and simulations the presence of simultaneity is confirmed introducing non economic factors transforms the character of the relationship between exogenous and endogenous variables from a diminishing returns to an increasing returns one the role played by public expenditure in education vaccination coverage low birth weight female schooling number of nurses access to safe water or malnutrition can be assessed as well as that played by structural adjustment variables such as the inflation rate or the external debt to gnp ratio infant and child mortality can be diminished everywhere in the region with relatively small amounts of expenditure disappointing outcomes in som

optimal monetary policy rules financial amplification and uncertain business cycles abstract this paper studies optimal monetary policy in the presence of uncertainty time variation in cross sectional dispersion of firms productive performance using a model with financial market imperfections the results suggest that i optimal policy is to dampen the strength of financial amplification by responding to uncertainty at the expense of creating mild degree of fluctuations in inflation ii higher uncertainty makes the welfare maximizing planner more willing to relax financial constraints iii credit spreads are a good proxy for uncertainty hence a non negligible response to credit spreads together with a strong anti inflationary policy stance achieves the highest aggregate welfare possible

equilibrium asset pricing with epstein zin and loss averse investors abstract we study multi period equilibrium asset pricing in an economy with epstein zin ez agents whose preferences for consumption are represented by recursive utility and with loss averse la agents who derive additional utility of gains and losses and are averse to losses we propose an equilibrium gain loss ratio for stocks and show that the la agents are more less risk averse than the ez agents if their degree of loss aversion is higher lower than this ratio when all the agents have unitary relative risk aversion degree and elasticity of intertemporal substitution we prove the existence and uniqueness of the equilibrium and the market dominance of the ez agents in the long run finally we extend our results to the case in which the la agents use probability weighting in their evaluation of gains and losses

stabilizing non fundamental asset price movements under discretion and limited information abstract inflation output and interest rate stabilization are all potential central bank objectives we explore whether monetary policy should respond to asset price fluctuations when they are driven by irrational expectational shocks to the future returns to capital in our model an optimistic shock to future returns generates both an increase in equity prices and physical investment the increased investment is inefficient and thus a central bank optimally responds to this expectations shocks this induces a trade off between stabilizing nominal prices and non fundamental asset price movements we compare the optimal policy under different assumptions full versus limited information and commitment versus discretion if the central bank has limited information about whether an asset price movement has a fundamental or non fundamental origin then the central bank responds less aggressively to the non fundamental exuberance shocks than under full information without commitment a central bank responds more aggressively to non fundamental exuberance shocks

can buy me love the effect of child welfare expenditures on maltreatment outcomes i consider the effect of state level child welfare expenditures on child abuse victimization and fatality rates the main result is that these expenditures are strongly associated with improved child maltreatment outcomes further the well known negative association between income and child abuse is overstated if one fails to control for relevant policy differences that are correlated with economic circumstances the effect of income diminishes further upon controlling for social attitudes correlated with income the source of identification is a set of large and explicitly exogenous changes in child welfare expenditures induced by the circa 2000 recession i show that endogeneity problems are small and tend to work against the result

markowitz with regret abstract providing a framework to integrate regret as an additional decision criterion in markowitz s model of portfolio selection we propose two different views on regret an investor might feel regret with respect to the ex post best alternative either in terms of return or in terms of preference value under both views regret can be captured by adjusting the vector of expected returns or alternatively by adjusting the return covariance matrix retaining the tractability of the markowitz model the regret model however has very different implications for how asset characteristics affect optimal portfolios while the impact of the skewness of an asset is strengthened the impact of the variance shrinks moreover we show for a variety of real portfolios that the effects of regret on optimal portfolio weights and the ex ante return distribution are large

learning monetary policy and asset prices this working paper should not be reported as representing the view s of the imf the views expressed in this working paper are those of the author s and do not necessarily represent those of the imf or imf policy working papers describe research in progress by the author s and are published to elicit comments and to further debate

violent crime a function of drug use or drug enforcement an assumption of many national drug control policies is the existence of a causal relationship between illegal drug use and violent crime however robust empirical findings supporting this relationship are scarce alternatively there is extensive research much of it in economics which suggests that there may actually be a stronger causal relationship between drug enforcement control prohibition and violent crime than drug use and criminal violence the paper presents some of the research pertaining to the relationship between illegal drugs and violent crime in addition a violent crime model is empirically tested using data from 24 metropolitan statistical areas msas in the united states to determine the nature and strength of this relationship

economic growth with bubbles this paper presents a stylized model of economic growth with bubbles this model views asset price bubbles as a market generated device to moderate the effects of frictions in financial markets improving the allocation of investments and raising the capital stock and welfare the model illustrates various channels through which asset price bubbles affect the incentives for innovation and economic reforms and therefore the rate of economic growth the model also offers a new perspective on the effects of financial development on asset price bubbles and economic growth

famous first bubbles t he jargon of economics and finance contains numerous colorful expressions to denote a market determined asset price at odds with any reasonable economic explanation such words as tulip mania bubble chain letter ponzi scheme panic crash and financial crisis immediately evoke images of frenzied and probably irrational speculative activity many of these terms have emerged from specific speculative episodes which have been sufficiently frequent and important that they underpin a strong current belief among economists that key capital markets sometimes generate irrational and inefficient pricing and allocational outcomes before economists relegate a speculative event to the inexplicable or bubble category however we must exhaust all reasonable economic explanations while such explanations are often not easily generated due to the inherent complexity of economic phenomena the business of economists is to find clever fundamental market explanations for events and our methodology should always require that we search intensively for market fundamental explanations before clutching the bubble last resort thus among the reasonable or market fundamental explanations i would include the perception of an increased probability of large returns the perception might be triggered by genuine economic good news by a convincing new economic theory about payoffs or by a fraud launched by insiders acting strategically to trick investors it might also be triggered by uninformed market participants correctly inferring changes in the distribution of dividends by observing price movements generated by the trading of informed insiders while some of these perceptions might

simple finite horizon bubbles robust to higher order knowledge an asymmetric information model of a finite horizon nth order rational asset price bubble is presented where all agents know that n the asset is worthless also the model has only two agents so the first order version of the bubble is simpler than other first order bubbles in the literature

the crash of ʼ87 was it expected the evidence from options markets transactions prices of s p 500 futures options over 1985 1987 are examined for evidence of expectations prior to october 1987 of an impending stock market crash first it is shown that out of the money puts became unusually expensive during the year preceding the crash second a model is derived for pricing american options on jump diffusion processes with systematic jump risk the jump diffusion parameters implicit in options prices indicate that a crash was expected and that implicit distributions were negatively skewed during october 1986 to august 1987 both approaches indicate no strong crash fears during the 2 months immediately preceding the crash attempts to explain what caused the stock market crashes around the world in october 1987 have suffered from the paucity of major economic developments occurring around that time that could have triggered the crashes shifting expectations regarding monetary policy foreign investors fears of a dollar decline increasing riskiness of assets none of these appeared major enough if present at all to explain the magnitude of the crashes and although portfolio insurance strategies could conceivably magnify the effects of a jump in fundamentals the initiating jump in fundamentals appears to be lacking

should central banks respond to movements in asset prices in recent decades asset booms and busts have been important factors in macroeconomic fluctuations in both industrial and developing countries in light of this experience how if at all should central bankers respond to asset price volatility we have addressed this issue in previous work bernanke and gertler 1999 the context of our earlier study was the relatively new but increasingly popular monetary policy framework known as inflation targeting see e g bernanke and frederic mishkin 1997 in an inflation targeting framework publicly announced medium term inflation targets provide a nominal anchor for monetary policy while allowing the central bank some flexibility to help stabilize the real economy in the short run the inflation targeting approach gives a specific answer to the question of how central bankers should respond to asset prices changes in asset prices should affect monetary policy only to the extent that they affect the central bank s forecast of inflation to a first approximation once the predictive content of asset prices for inflation has been accounted for there should be no additional response of monetary policy to assetprice fluctuations in use now for about a decade inflationtargeting has generally performed well in practice however so far this approach has not often been stress tested by large swings in asset prices our earlier research employed simulations of a small calibrated macroeconomic model to examine how an inflation targeting policy defined as one in which the central bank s instrument interest rate responds primarily to changes in expected inflation might fare in the face of a boom and bust cycle in asset prices we found that an aggressive inflationtargeting policy rule in our simulations one in which the coefficient relating the instrument interest rate to expected inflation is 2 0 substantially stabilizes both output and inflation in scenarios in which a bubble in stock prices develops and then collapses as well as in scenarios in which technology shocks drive stock prices intuitively inflation targeting central banks automatically accommodate productivity gains that lift stock prices while offsetting purely speculative increases or decreases in stock values whose primary effects are through aggregate demand conditional on a strong policy response to expected inflation we found little if any additional gains from allowing an independent response of central bank policy to the level of asset prices in our view there are good reasons outside of our formal model to worry about attempts by central banks to influence asset prices including the fact that as history has shown the effects of such attempts on market psychology are dangerously unpredictable hence we concluded that inflationtargeting central banks need not respond to asset prices except insofar as they affect the inflation forecast in the spirit of recent work on robust control the exercises in our earlier paper analyzed the performance of policy rules in worst case discussants robert shiller yale university glenn rudebusch federal reserve bank of san francisco kenneth rogoff harvard university

discrete time behavioral portfolio selection under cumulative prospect theory we formulate and study three multi period behavioral portfolio selection models under cumulative prospect theory i s shaped utility maximization without probability weighting in a market with one risky asset ii s shaped utility maximization without probability weighting in a market with multiple risky assets which follow a joint elliptical distribution and iii s shaped utility maximization with inverse s shaped probability weighting in a market with one risky asset for the first two time consistent models we identify the well posedness conditions and derive the semi analytical optimal policies for the third time inconsistent model we assume that the investor is aware of the time inconsistency but is unable to commit to his initial plan of action then we reformulate the model into an intrapersonal game model and derive the semi analytical subgame perfect nash equilibrium time consistent policy under well posedness condition all the three policies take a piecewise linear feedback form our analysis of the three models not only partially explains the well documented phenomena of non participation puzzle and horizon effect but also extends the two fund separation theorem into multi period s shaped utility setting and pushes forward the study on time inconsistency issue incurred by probability weighting

self coordination in time inconsistent stochastic decision problems a planner doer game framework abstract time inconsistency has been a thorny issue in many economic and financial decision making problems especially when risk measures are involved in performance criteria we develop in this paper a two tier planner doer game framework with self coordination by aligning the global interest of the planner and the local interests of the doers by applying suitable penalty functions a degree of internal harmony measured quantitatively by the expected cost of self coordination can be achieved by the self coordination policy we establish an axiom system for modified preferences under which the self coordination policy can be obtained by solving a corresponding optimization problem we then apply our game framework successfully in dynamic mean variance portfolio selection

rational asset pricing bubbles this paper provides a fairly systematic study of general economic conditions under which rational asset pricing bubbles may arise in an intertemporal competitive equilibrium framework our main results are concerned with nonexistence of asset pricing bubbles in those economies these results imply that the conditions under which bubbles are possible including some well known examples of monetary equilibria are relatively fragile this paper is concerned with the conditions under which asset prices in an intertemporal competitive equilibrium are equal to the present value of the streams of future dividends to which each asset represents a claim according to a central result of the theory of finance this is very generally true in the case of economies with trading at only a finite sequence of dates as long as there are no restrictions upon transactions other than that associated with possible incom pleteness of the set of securities that are traded the result is sometimes called the fundamental theorem of asset pricing here we consider the extent to which such a result continues to be valid in the case of trading over an infinite horizon it has often been observed in the econometric literature on asset pricing bubbles that it is possible in principle for the price of a perpetuity and the dividends on that security to satisfy at all times a present value relation for one period holding returns while the security s price nonetheless does not equal the present value of the stream of dividends expected over the infinite future in such a case the price of the perpetuity is said to involve a bubble component 2 joint stochastic processes for which this component is nonzero are sometimes argued to characterize existing assets for a recent example see froot and obstfeld 1991 but such an inference depends upon aspects of the stochastic

monetary policy and asset prices with belief driven fluctuations abstract we present a heterogeneous agents new keynesian model subject to a cost channel of monetary policy transmission constant turnover between long time traders and newcomers in market activities combined with restricted trading opportunities introduces a feedback from the stock market to real activity making stock prices non redundant for the business cycle we show that strict inflation targeting can lead to equilibrium indeterminacy even if the policy rule satisfies the taylor principle a belief driven shock to stock price generates relative volatilities of key financial variables which are very close to what is observed in u s data this result hints to the possibility that the financial instability witnessed since the mid to late 1990s was the result of waves of rational exuberance and pessimism in financial markets our analysis suggests that a mild response to stock prices in the central bank s policy rule can restore equilibrium determinacy and therefore rule out non fundamental volatility

monetary policy and rational asset price bubbles i examine the impact of alternative monetary policy rules on a rational asset price bubble through the lens of an olg model with nominal rigidities a systematic increase in interest rates in response to a growing bubble is shown to enhance the uctuations in the latter

dynamic portfolio choice and asset pricing with narrow framing and probability weighting this paper shows that the framework proposed by barberis and huang 2009 to incorporate narrow framing and loss aversion into dynamic models of portfolio choice and asset pricing can be extended to also account for probability weighting and for a value function that is convex on losses and concave on gains we show that the addition of probability weighting and a convex concave value function reinforces previous applications of narrow framing and cumulative prospect theory to understanding the stock market non participation puzzle and the equity premium puzzle moreover we show that a convex concave value function generates new wealth effects that are consistent with empirical observations on stock market participation

inflation targeting learning and q volatility in small open economies this paper examines the welfare implications of managing asset price with consumer price inflation targeting by monetary authorities who have to learn the laws of motion for both inflation rates the central bank can reduce the volatility of consumption as well as improve welfare more effectively if it adopts state contingent taylor rules aimed at inflation and q growth targets in this learning environment however under perfect model certainty pure inflation targeting dominates combined consumer and asset price inflation targeting

heterogeneous beliefs and housing market boom bust cycles abstract this paper presents a business cycle model capturing the stylized features of housing market boom bust cycles in developed countries the model implies that over optimism of mortgage borrowers generates housing market boom bust cycles if mortgage borrowers are credit constrained and savers do not share their optimism this result holds without price stickiness if price stickiness is introduced into the model then the model replicates a low policy interest rate during a housing boom as an endogenous reaction to a low inflation rate given a taylor rule thus monetary easing observed during housing booms are consistent with the presence of over optimism causing boom bust cycles

rethinking monetary policy after the crisis abstract this lecture examines how the recent global financial crisis changes our thinking about how monetary policy should be conducted it starts with a discussion of the science and practice of monetary policy before the crisis and then uses the lessons from the crisis to argue how the practice of monetary policy should be rethought along six dimensions flexible inflation targeting response to asset price bubbles dichotomy between monetary policy and financial stability policy risk management and gradualism fiscal dominance and forward guidance

beauty contests and iterated expectations in asset markets in a financial market where traders are risk averse and short lived and prices are noisy asset prices today depend on the average expectation today of tomorrow s price thus iterating this relationship the date 1 price equals the date 1 average expectation of the date 2 average expectation of the date 3 price this will not in general equal the date 1 average expectation of the date 3 price we show how this failure of the law of iterated expectations for average belief can help understand the role of higher order beliefs in a fully rational asset pricing model and explain over reaction to noisy public information

should central banks burst bubbles some microeconomic issues anti bubble policy is examined in a finite horizon greater fool bubble model with rational agents asymmetric information and short sales constraints this permits the use of standard tools of welfare economics to analyse bubble policies policy is modelled as deflating overpriced assets by revealing information about this overpricing if the central bank is following such a policy then the market interprets inaction as an implicit endorsement of asset prices which raises these prices also the central bank can deflate overpriced assets even if it has no informational advantage over any investors about this overpricing however unless it has such an informational advantage a bubble bursting rule may only make things worse

finite bubbles with short sale constraints and asymmetric information abstract we present a finite period general equilibrium model of an exchange economy with asymmetric information we say that a rational expectations equilibrium exhibits a strong bubble if the price is higher than the dividend with probability one we show that necessary conditions for a strong bubble to occur are that 1 each agent must have private information in the period and state in which the bubble occurs 2 each agent must be short sale constrained at some period in the future with positive probability and 3 agents trades are not common knowledge we present examples of bubbles when the necessary conditions are satisfied journal of economic literature classification numbers c72 d52 d82 d84 g12 g14

an incentive model of the effect of parental income on children economists explain the positive relationship between parental income and children s outcomes using an investment model building on work in psychology and sociology this paper emphasizes the importance of child rearing practices which vary with income i argue that parents ability to mold their children s behavior through pecuniary incentives is limited at low incomes leading to lower outcomes and increased reliance on nonpecuniary mechanisms such as corporal punishment my model generates a positive relationship between parental income and children s outcomes especially at low incomes and endogenously produces a relationship between parental income and child rearing practices empirical work confirms these implications

dynamic trading with reference point adaptation and loss aversion we formalize the reference point adaptation process by relating it to a way people perceive prior gains and losses we then develop a dynamic trading model with reference point adaptation and loss aversion and derive its semi analytical solution the derived optimal stock holding has an asymmetric v shaped form with respect to prior outcomes and the related sensitivities are directly determined by the sensitivities of reference point shifts with respect to the outcomes we also find that the effects of reference point adaptation can be used to shed light on some well documented trading patterns e g house money break even and disposition effects

a model of casino gambling we show that prospect theory offers a rich theory of casino gambling one that captures several features of actual gambling behavior first we demonstrate that for a wide range of preference parameter values a prospect theory agent would be willing to gamble in a casino even if the casino offers only bets with no skewness and with zero or negative expected value second we show that the probability weighting embedded in prospect theory leads to a plausible time inconsistency at the moment he enters a casino the agent plans to follow one particular gambling strategy but after he starts playing he wants to switch to a different strategy the model therefore predicts heterogeneity in gambling behavior how a gambler behaves depends on whether he is aware of the time inconsistency and if he is aware of it on whether he can commit in advance to his initial plan of action this paper was accepted by brad barber teck ho and terrance odean special issue editors

why do increased arrest rates appear to reduce crime deterrence incapacitation or measurement error this paper attempts to discriminate between deterrence incapacitation and measurement error as explanations for the negative empirical relationship between arrest rates and crime measurement error cannot explain the observed patterns in the data incapacitation suggests that an increase in the arrest rate for one crime will reduces all crime rates deterrence predicts that an increase in the arrest rate for one crime will lead to a rise in other crimes as criminals substitute away from the first crime empirically deterrence appears to be the more important factor particularly for property crimes jel k42

the information technology revolution and the stock market technological progress comes in waves the british industrial revolution 1760 1850 ushered in cort s puddling and rolling process for making iron crompton s mule for spinning cotton and the watt steam engine the second industrial revolution 1890 1930 witnessed the rise of electricity the internal combustion engine and the chemical industry the birth of information technology it may herald the start of a third industrial revolution a new technology or product is often developed by the single entrepreneur who initially finds it hard to get funds develop the product and find customers but if the product is good customers eventually line up and investors flock in other firms then move in to make the product and may drive the innovator out or acquire him whether he reaches the initial public offering ipo stage or is acquired by a listed firm though it takes time for the innovator to add value to the stock market indeed the innovation may at first reduce the market s value because some firms usually large or old will cling to old technologies that have lost their momentum figure 1 plots the market value of u s equity relative to gdp this paper argues that a the market declined in the late 1960 s because it felt that the old technologies either had lost their momentum or would give way to it and that b it innovators boosted the stock market s value only in the 1980 s if the stock market provides a forecast of future events then the recent dramatic upswing represents a rosy estimate about growth in future profits for the economy this translates into a forecast of higher output and productivity growth holding other things equal such as capital s share