analyst forecasting errors additional evidence analyst forecasting errors are approximately as large as dreman and berry 1995 documented and an optimistic bias is evident for all years from 1985 through 1996 in contrast to their findings i show that analyst forecasting errors and bias have decreased over time moreover the optimistic bias in quarterly forecasts was absent for sp 2 firms with comparatively large amounts of market capitalization absolute value of earnings forecast and analyst following and 3 firms in certain industries

the impact of uncertainty shocks in emerging economies abstract a recent strand of research proposes that sudden jumps in uncertainty generate rapid drops and recoveries in real macroeconomic variables that drive the business cycle using an empirical model we find substantial heterogeneity in reactions to these shocks across countries in comparison to the u s and other developed countries emerging economies suffer much more severe falls in investment and private consumption following an exogenous uncertainty shock take significantly longer to recover and do not experience a subsequent overshoot in activity we provide evidence that the dynamics of investment and consumption are correlated with the depth of financial markets we control for the potential role of a credit channel and estimate that it can account for up to one half of the increased fall in investment generated by uncertainty shocks among emerging economies with less developed financial markets in this context monetary and fiscal policy actions that alleviate the impact of credit constraints facing firms may reduce the impact of uncertainty shocks in these economies

non zero sum stochastic differential reinsurance and investment games with default risk this paper investigates the implications of strategic interaction i e competition between two cara insurers on their reinsurance investment policies the two insurers are concerned about their terminal wealth and the relative performance measured by the difference in their terminal wealth the problem of finding optimal policies for both insurers is modelled as a non zero sum stochastic differential game the reinsurance premium is calculated using the variance premium principle and the insurers can invest in a risk free asset a risky asset with heston s stochastic volatility and a defaultable corporate bond we derive the nash equilibrium reinsurance policy and investment policy explicitly for the game and prove the corresponding verification theorem the equilibrium strategy indicates that the best response of each insurer to the competition is to mimic the strategy of its opponent consequently either the reinsurance strategy or the investment strategy of an insurer with the relative performance concern is riskier than that without the concern numerical examples are provided to demonstrate the findings of this study

precautionary savings and self selection evidence from the german reunification experiment in the absence of complete insurance expected future income shocks lead prudent individuals to build up precautionary savings in order to avoid wide fluctuations in the consumption path the reaction of savings to expected future shocks is stronger the more risk averse an individual is risk aversion might influence not only the savings behavior of an individual facing a stochastic income path but it can also affect occupational choice in the first place in particular risk averse individuals might choose occupations that are associated with less risky income paths while less risk averse individuals might prefer occupations with higher income risk assessing the importance of self selection of individuals into occupations according to their risk aversion is difficult since risk aversion is usually unobserved yet failing to control for unobserved risk aversion in regressions of wealth on measures of labor income risk will lead to a bias if selfselection takes place since measures of labor income risk will be negatively correlated with the error term that is capturing the unobserved risk aversion this could lead to a rejection of the theory of precautionary savings even if individuals act according to the theory

martingales and arbitrage in securities markets with transaction costs abstract we derive the implications from the absence of arbitrage in dynamic securities markets with bid ask spreads the absence of arbitrage is equivalent to the existence of at least an equivalent probability measure that transforms some process between the bid and the ask price processes of traded securities into a martingale the martingale measures can be interpreted as possible linear pricing rules and can be used to determine the investment opportunities available in such an economy the minimum cost at which a contingent claim can be obtained through securities trading is its largest expected value with respect to the martingale measures journal of economic literature classification numbers g11 g12 g13 d52 and d90

unemployment risk and precautionary wealth evidence from households balance sheets this paper examines precautionary behavior by relating job loss risk to household net worth we use existing best practice and some new strategies to deal with some problematic issues inherent in this literature regarding proxying uncertainty instrumentation and incorporating theoretical restrictions we do not find precautionary variation in the wealth holdings of households with low permanent income but do find precautionary effects for moderate and higher income households when the dependent variable is total net worth these findings are robust to several alternative specifications but we do not find precautionary responses in subaggregates of wealth that exclude home equity

comparisons and combinations of long and long short strategies market neutral long short strategies get their returns from alphas and short rebates long strategies get their returns from alpha and the market differing return and risk sources complicate their comparison partly because of the strong market referenced focus of conventional performance analysis compelling theoretical advantages of active return per unit of active risk suggest that long short strategies are better able to deliver excess return than are conventional institutional long strategies long short strategies even with tiny positive alphas are seen to improve investors efficient frontiers when added to a traditional t bill long portfolio mix mostly because their risk sources are uncorrelated surprisingly the improvement occurs even if long short strategies are sharpe ratio inferior to long strategies these results provide theoretical support for including long short strategies in most investors mix of assets

the efficiency gains of long short investing long short strategies have generated controversy and institutional interest for more than 10 years we analyzed the efficiency gains of long short investing where we defined efficiency as the information ratio of the implemented strategy the optimal portfolio relative to the intrinsic information ratio of the alphas the efficiency advantage of long short investing arises from the loosening of the surprisingly important long only constraint long short and long only managers need to understand the impact of this significant constraint long short implementations offer the most improvement over long only implementations when the universe of assets is large asset volatility is low and the strategy has high active risk the long only constraint induces biases particularly toward small stocks limits the manager s ability to act on upside information by not allowing short positions that could finance long positions and reduces the efficiency of traditional high risk long only strategies relative t

how important is precautionary saving we estimate how much of the wealth of a sample of psid respondents is held because some households face more income uncertainty than others we begin by solving a theoretical model of saving which we use to develop appropriate measures of uncertainty we then regress measures of wealth on our measures of uncertainty and find evidence that households engage in precautionary saving finally we simulate the wealth distribution that our empirical results imply would prevail if all households had the same uncertainty as the lowest uncertainty group we find that between 39 and 46 percent of wealth in our sample is attributable to the extra uncertainty that some consumers face compared to the lowest uncertainty group

household saving micro theories and micro facts in this survey we review the recent theoretical and empirical literature on household saving and consumption the discussion is structured around a list of motives for saving and how well the standard theory captures these motives we show that almost all of the motives for saving that have been suggested in the informal saving literature can be captured in the standard optimizing model particular attention is given to recent work on the precautionary motive and its implications for saving and consumption behavior we also discuss the behavioral or psychological approach that eschews the use of standard optimization techniques and focuses instead on direct consideration on saving we provide a section on facts who save and how much we then discuss informally the recent decline in the u s saving rate and whether the theory is of much use in understanding this and other changes in aggregate saving rates over time we do not find any convincing explanation for the change in saving rates we also discuss some analyses of saving behavior over the life cycle addressing such questions as whether households save enough for retirement and whether the consumption patterns of older households can be rationalized within a simple life cycle model we also review a great number of studies of the consumption euler equations based on our analysis of the studies cited we conclude that there is still mixed evidence that consumption is excessively sensitive to income we also examine in depth the recent empirical literature on the precautionary motive we conclude that although some households do seem to have a significant precautionary motive at some points in their life cycle this motive is not so strong empirically as some investigators suggest

the nature of precautionary wealth abstract this paper uses the panel study of income dynamics to provide some of the first direct evidence that wealth is systematically higher for consumers with predictably greater income uncertainty however the apparent pattern of precautionary wealth is not consistent with a standard parameterization of the life cucle model in which consumers are patient enough to begin saving for retirement early in life wealth is estimated to be far less sensitive to uncertainty than implied by that model instead our results suggest that over most of their working life time consumers behave in accordance with the buffer stock models of saving described in carroll 1992 1997 or deaton 1991 in which consumers hold wealth principally to insulate consumption against near term fluctuations in income

unemployment insurance and precautionary saving abstract models of precautionary saving imply that households will hold more assets when faced with greater income uncertainty however previous empirical studies of income uncertainty have produced somewhat mixed support for the precautionary saving hypothesis in this paper we note that differences in the state contingent income stream available to workers through the unemployment insurance ui program provides an excellent source of variation for testing the presence of a precautionary savings motive simulations of a stochastic life cycle model suggest that a ui system similar to the type currently in place in the u s can lead to a significant reduction in the assets accumulated by a median worker moreover there is considerable variation in the ui benefit schedules for workers living in different states in the u s which provides an exogenous source of variation for empirically testing the precautionary saving hypothesis we carry out this test using data on expected ui benefit replacement rates and financial assets held by households in the survey of income and program participation our empirical results are consistent with the predictions of the model and suggest that reducing the ui benefit replacement rate by 50 percent would increase gross financial asset holdings by 14 percent or 241 for the average worker we also find empirical evidence that this crowd out effect of ui on household saving is stronger for those facing higher unemployment risk and weaker for older workers both of which are implications from our precautionary saving model

an expenditure based estimate of britain s black economy abstract we estimate the size of britain s black economy defined narrowly as unreported taxable income by using income and expenditure data drawn from the 1982 family expenditure survey our working assumptions are that all income groups report expenditure on food correctly employees in employment report income correctly and that the self employed under report their income we estimate food exependiture equations for all groups and then invert them to arrive at the conclusion that on average true self employment income is 1 55 times as much as reported self employment income this implies that the size of the black economy is about 5 5 percent of gdp

impact of economic uncertainty in a small open economy the case of chile we construct the first news based economic uncertainty index for chile which allowed us to rebuild 23 years of the history of economic uncertainty in the country and quantify its impact on the eco

precautionary savings and the self employed this work focuses on the impact of uncertainty on savings under bequest form specifically we estimate whether and to what extent income variability does have an effect on post mortem savings we approximate the post mortem savings with the closest dedicated savings which is savings in term insurance a lump sum inherited at the death of the subscriber furthermore we test whether the intensity of the income variance or the riskiness of the job type such as self employment matters more in the choice our results show that self employment status is one of the most relevant variables affecting term insurance ownership

leverage aversion and portfolio optimality portfolio volatility is the only source of risk in mean variance optimality but it fails to capture all the risks faced by leveraged portfolios these risks include the possibility of margin calls and forced liquidations at adverse prices and losses beyond the capital invested to recognize these risks the authors incorporated leverage aversion into the optimization process and examined the effects of volatility and leverage aversion on optimal long short portfolios

trading volume and serial correlation in stock returns this paper investigates the relationship between aggregate stock market trading volume and the serial correlation of daily stock returns for both stock indexes and individual large stocks the first order daily return autocorrelation tends to decline with volume the paper explains this phenomenon using a model in which risk averse market makers accommodate buying or selling pressure from liquidity or noninformational traders changing expected stock returns reward market makers for playing this role the model implies that a stock price decline on a high volume day is more likely than a stock price decline on a low volume day to be associated with an increase in the expected stock return

precautionary saving and subjective earnings variance abstract in this paper i examine a model of precautionary saving and i show that the fact that people may insure against income risk makes it difficult to evaluate the extent of precautionary accumulation by simply looking at the relationship between wealth and earnings variance i also argue that occupations may represent a bad proxy for income risk

the behavior of stock prices around institutional trades all trades executed by 37 large investment management firms from july 1986 to december 1988 are used to study the price impact and execution cost of the entire sequence package of trades that we interpret as an order we find that market impact and trading cost are related to firm capitalization relative package size and most importantly to the identity of the management firm behind the trade money managers with high demands for immediacy tend to be associated with larger market impact financial economists have long studied the equity trading process and its impact on stock prices much prior empirical research isolates individual trades and analyzes the behavior of the stock price around each trade see for example kraus and stoll 1972a holthausen leftwich and mayers 1987 1990 keim and madhavan 1991 petersen and umlauf 1991 hausman lo and mackinlay 1992 and chan and lakonishok 1993 evaluating the behavior of stock prices around trades provides a means of discriminating among various hypotheses as to the elasticity of the demand for stocks yields an estimate of the cost of executing trades and a measure of the liquidity of a market and permits tests of different models of the determination of quotes and transaction prices for many institutional investors however even a moderately sized position in a stock may represent a large fraction of the stock s trading volume accordingly an investment manager s order is often broken up into several trades it is often misleading therefore to consider an individual trade as the basic unit of analysis in the study of trading activity and its effects on prices this paper uses the record of trades executed by 37 large investment manage

saving and liquidity constraints this paper is concerned with the theory of saving when consumers are not permitted to borrow and with the ability of such a theory to account for some of the stylized facts of saving behavior the models presented in the paper seem to account for important aspects of reality that are not explained by traditional life cycle models copyright 1991 by the econometric society

fundamentals of efficient factor investing corrected may 2017 combining long only constrained factor subportfolios is generally not a mean variance efficient way to capture expected factor returns for example a combination of four fully invested factor subportfolios low beta small size value and momentum captures less than half e g 40 of the potential improvement over the market portfolio s sharpe ratio in contrast a long only portfolio of individual securities using the same risk model and return forecasts captures most e g 80 of the potential improvement we adapt traditional portfolio theory to more recently popularized factor based investing and simulate optimal combinations of factor and security portfolios using the largest 1 000 common stocks in the us equity market from 1968 to 2015

60 years of portfolio optimization practical challenges and current trends abstract the concepts of portfolio optimization and diversification have been instrumental in the development and understanding of financial markets and financial decision making in light of the 60 year anniversary of harry markowitz s paper portfolio selection we review some of the approaches developed to address the challenges encountered when using portfolio optimization in practice including the inclusion of transaction costs portfolio management constraints and the sensitivity to the estimates of expected returns and covariances in addition we selectively highlight some of the new trends and developments in the area such as diversification methods risk parity portfolios the mixing of different sources of alpha and practical multi period portfolio optimization

the importance of business owners in assessing the size of precautionary savings abstract not properly accounting for differences between business owners and nonbusiness owners in studies of household wealth can lead to erroneous conclusions about the significance of different saving motives using data from the panel study of income dynamics from the 1980s and 1990s we show that within samples of both business owners and non business owners the amount of precautionary savings with respect to labor income risk is modest and accounts for less than 10 of total household wealth previous large estimates of the size of precautionary balances resulted from pooling these two groups together such pooling is inappropriate given that business owners face higher labor risk and accumulate more wealth than non business owners for reasons unrelated to precautionary motives

measuring the well being of the poor using income and consumption we examine the relative merits of consumption and income as measures of the material well being of the poor consumption offers several advantages over income because consumption is a more direct measure of well being than income and is less subject to underreporting bias measurement problems with income are problematic for analyses of changes in well being of the poor because the biases appear to have changed over time and are correlated with government policies on the other hand income is often easier to report and is available for much larger samples providing greater power to test hypotheses we begin by considering the conceptual and pragmatic reasons why consumption might be better or worse than income then we employ several empirical strategies to examine the quality of income and consumption data first we compare income and consumption reports for those with few resources as well as their assets and liabilities to examine measurement errors and under reporting second we examine other evidence on the internal consistency of reports of low income or consumption third we compare how well micro data in standard datasets weight up to match aggregates for classes of income and consumption that are especially important for low resource families fourth we validate income and consumption measures by comparing them to other measures of hardship or material well being although the evidence tends to favor consumption measures our analyses suggest that both measures should be used to assess the material well being of the poor

risk management housing and stockholding this article investigates the possible explanations of the stockholding puzzle by focusing on housing and other uninsurable risks associated with income health and business taking the french household wealth survey patrimoine 2004 french national statistical institute we find that the share of financial wealth invested in stocks depends on transaction and information costs risk aversion exposure to real estate risk and to a lesser extent labour market risk these results are obtained by controlling for endogenous home ownership status

dynamic portfolio optimization with transaction costs heuristics and dual bounds we consider the problem of dynamic portfolio optimization in a discrete time finite horizon setting our general model considers risk aversion portfolio constraints e g no short positions return predictability and transaction costs this problem is naturally formulated as a stochastic dynamic program unfortunately with nonzero transaction costs the dimension of the state space is at least as large as the number of assets and the problem is very difficult to solve with more than one or two assets in this paper we consider several easy to compute heuristic trading strategies that are based on optimizing simpler models we complement these heuristics with upper bounds on the performance with an optimal trading strategy these bounds are based on the dual approach developed in brown et al brown d b j e smith p sun 2009 information relaxations and duality in stochastic dynamic programs oper res 58 4 785 801 in this context these bounds are given by considering an investor who has access to perfect information about future returns but is penalized for using this advance information these heuristic strategies and bounds can be evaluated using monte carlo simulation we evaluate these heuristics and bounds in numerical experiments with a risk free asset and 3 or 10 risky assets in many cases the performance of the heuristic strategy is very close to the upper bound indicating that the heuristic strategies are very nearly optimal this paper was accepted by dimitris bertsimas optimization

consumption puzzles and precautionary savings abstract when marginal utility is convex agents accumulate savings as a precautionary measure against labor income eventualities this paper shows that precautionary savings can go a long way in making the excess growth excess smoothness and excess sensitivity features of consumption consistent with the stochastic processes of labor income observed in the u s at the microeconomic level

fluctuations in uncertainty this review article tries to answer four questions i what are the stylized facts about uncertainty over time ii why does uncertainty vary iii do fluctuations in uncertainty matter and iv did higher uncertainty worsen the great recession of 2007 2009 on the first question both macro and micro uncertainty appears to rise sharply in recessions on the second question the types of exogenous shocks like wars financial panics and oil price jumps that cause recessions appear to directly increase uncertainty and uncertainty also appears to endogenously rise further during recessions on the third question the evidence suggests uncertainty is damaging for short run investment and hiring but there is some evidence it may stimulate longer run innovation finally in terms of the great recession the large jump in uncertainty in 2008 potentially accounted for about one third of the drop in gdp

a model of competitive stock trading volume a model of competitive stock trading is developed in which investors are heterogeneous in their information and private investment opportunities and rationally trade for both informational and noninformational motives i examine the link between the nature of heterogeneity among investors and the behavior of trading volume and its relation to price dynamics it is found that volume is positively correlated with absolute changes in prices and dividends i show that informational trading and noninformational trading lead to different dynamic relations between trading volume and stock returns

on the optimality of long short strategies we consider the optimality of portfolios not subject to short selling constraints and derive conditions that a universe of securities must satisfy for an optimal active portfolio to be dollar neutr

permanent income current income and consumption evidence from two panel data sets in this article i estimate euler equations that is the first order conditions of the consumers maximization problem using data from two data sets consumption data are taken from the consumer expenditure survey income data are taken from the panel study of income dynamics because the data for the estimation come from two samples i use a generalization of the instrumental variables estimator the two sample instrumental variables estimator i find evidence that consumption is excessively sensitive to predictable income growth the estimates of the coefficient of excess sensitivity for three consumption measures range from 2 to 5

portfolio constraints and the fundamental law of active management active portfolio management is typically conducted within constraints that do not allow managers to fully exploit their ability to forecast returns constraints on short positions and turnover for example are fairly common and materially restrictive other constraints such as market capitalization and value growth neutrality with respect to the benchmark or economic sector constraints can further restrict an active portfolio s composition we derive ex ante and ex post correlation relationships that facilitate the performance analysis of constrained portfolios the ex ante relationship is a generalized version of a previously developed fundamental law of active management and provides an important strategic perspective on the potential for active management to add value the ex post correlation relationship represents a practical decomposition of performance into the success of the return prediction process and the noise associated with portfolio constraints we verify the accuracy of these relati

the surprisingly low importance of income uncertainty for precaution abstract while it is common to use income uncertainty to explain household saving decisions there is much disagreement about the importance of precautionary saving this paper suggests that income uncertainty is not an important motive for saving although households do have other precautionary reasons to save using a question from the survey of consumer finances that asks how much households want for precautionary purposes this paper shows that expressed household preferences and liquid savings are much lower than predicted by standard modeling assumptions households rarely list unemployment as a reason to save perceived income uncertainty does not affect liquid savings or precautionary preferences neither does being in an occupation with higher income volatility instead households seem very concerned with expenditure shocks

welfare impacts of improved chickpea adoption a pathway for rural development in ethiopia we analyse the impact of improved chickpea adoption on welfare in ethiopia using three rounds of panel data first we estimate the determinants of improved chickpea adoption using a double hurdle model we apply a control function approach with correlated random effects to control for possible endogeneity resulting from access to improved seed and technology transfer activities to instrument for these variables we develop novel distance weighted measures of a household s neighbours access to improved seed and technology transfer activities second we estimate the impact of area under improved chickpea cultivation on household income and poverty we apply a fixed effects instrumental variables approach where we use the predicted area under cultivation from the double hurdle model as an instrument for observed area under cultivation we find that improved chickpea adoption significantly increases household income while also reducing household poverty finally we disaggregate results by landholding to explore whether the impact of adoption has heterogeneous effects adoption favoured all but the largest landholders for who the new technology did not have a significant impact on income overall increasing access to improved chickpea appears a promising pathway for rural development in ethiopia s chickpea growing regions

uncertainty shocks and unemployment dynamics in u s recessions abstract what are the effects of uncertainty shocks on unemployment dynamics we answer this question by estimating non linear smooth transition vars with post wwii u s data the relevance of uncertainty shocks is found to be much larger than that predicted by standard linear vars in terms of i magnitude of the reaction of the unemployment rate to such shocks and ii contribution to the variance of the prediction errors of unemployment at business cycle frequencies the ability of different classes of dsge models to replicate our results is discussed

optimal consumption choices for a large investor abstract this paper examines the optimal consumption and investment problem for a large investor whose portfolio choices affect the instantaneous expected returns on the traded assets alternatively our analysis can be interpreted in terms of an optimal growth problem with nonlinear technologies existence of optimal policies is established using martingale and duality techniques under general assumptions on the securities price process and the investor s preferences as an illustration of our characterization result explicit solutions are provided for specific examples involving an agent with logarithmic utilities and a generalized two factor version of the ccapm is derived the analogy of the consumption problem examined in this paper to the consumption problem with constraints on the portfolio choices is emphasized

how prudent are consumers using data from the consumer expenditure survey this paper presents a simple test that provides an explicit estimate of the parameter in the utility function that reflects the strength of the precautionary saving motive the coefficient of relative prudence the test yields a fairly precise estimate of a small precautionary motive in fact the estimate is too small to be consistent with widely accepted beliefs about risk aversion the presence of liquidity constrained households does not appear to explain this finding and there is some evidence that self selection of households into risky environments also cannot explain the results

performance attribution and the fundamental law the reported study operationalized the fundamental law of active management in the context of a factor based performance attribution system the system incorporates factor payoffs in the linear regression framework that many portfolio managers and external reviewers use to judge what is being rewarded in the market the study indicates that parameters of the fundamental law can be used to approximate and interpret the results of the regression based performance attribution system the procedure is illustrated by the use of security holdings returns and factor exposure data for two portfolios benchmarked to the s p 500 index for april 1995 to march 2004

precautionary savings of agents with heterogeneous risk aversion this article focuses on the estimation of the importance of the precautionary motive in the wealth accumulation decision we use the micro data set of the de nederlandsche bank dnb household survey dhs centerdata tilburg university a dutch household survey containing information on wealth a subjective measure of income uncertainty and subjective qualitative measures of risk aversion we find that only a small share of wealth is accumulated for the precautionary motive by the dutch households this share of wealth is constant across assets with different degrees of liquidity the economic downturn of the period 2008 to 2010 seems to affect risk attitudes and precautionary saving our findings also suggest that the more risk averse individuals are those who hold less savings

on the strategic behavior of large investors a mean variance portfolio approach abstract one key assumption of markowitz s model is that all traders act as price takers in this paper we extend this mean variance approach in a setting where large investors can move prices instead of having an individual optimization problem we find the investors nash equilibrium and redefine the efficient frontier in this new framework we also develop a simplified application of the general model with two assets and two investors to shed light on the potential strategic behavior of large and atomic investors our findings validate the claim that large investors enhance their portfolio performance in relation to perfect market conditions besides we show under which conditions atomic investors can benefit in relation to the standard setting even if they have not total influence on their eventual performance the two investors two assets setting allows us to quantify performance and do sensitivity analysis regarding investors market power risk tolerance and price elasticity of demand finally for a group of well known etfs we empirically show how price variations change depending on the volume traded we also explain how to set up and use our model with real market data

consumption versus expenditure previous authors have documented a dramatic decline in food expenditures at the time of retirement we show that this is matched by an equally dramatic rise in time spent shopping for and preparing meals using a novel data set that collects detailed food diaries for a large cross section of u s households we show that neither the quality nor the quantity of food intake deteriorates with retirement status we also show that unemployed households experience a decline in food expenditure and food consumption commensurate with the impact of job displacement on permanent income these results highlight how direct measures of consumption distinguish between anticipated and unanticipated shocks to income whereas measures of expenditures obscure the distinction