interpreting economic time series this paper explores some of the implications for econometric practice of the principle that people s observed behavior will change when their constraints change in dynamic contexts a proper definition of people s constraints includes among them laws of motion that describe the evolution of the taxes they must pay and the prices of the goods that they buy and sell changes in agents perceptions of these laws of motion or constraints will in general produce changes in the schedules that describe the choices they make as a function of the information that they possess until very recently received dynamic econometric practice ignored this principle the practice of dynamic econometrics should be changed so that it is consistent with the principle that people s rules of choice are influenced by their constraints this is a substantial undertaking and involves major adjustments in the ways that we formulate estimate and simulate econometric models

cake eating exhaustible resource extraction life cycle saving and non atomic games existence theorems for a class of optimal allocation problems abstract this paper investigates the problem concerning the existence of a solution to a diverse class of optimal allocation problems which include models of cake eating exhaustible resource extraction life cycle saving and non atomic games a new formulation that encompasses all these diverse models is provided examples of these models for which a solution does not exist and the causes of the non existence are studied two theorems are provided to tackle the existence problem under different conditions several analytical examples with a closed form solution are offered to illustrate the usefulness of the existence theorems

the american business cycle continuity and change in recent decades the american economy has experienced the worst peace time inflation in its history and the highest unemployment rate since the great depression these circumstances have prompted renewed interest in the concept of business cycles which joseph schumpeter suggested are like the beat of the heart of the essence of the organism that displays them in the american business cycle some of the most prominent macroeconomics in the united states focuses on the questions to what extent are business cycles propelled by external shocks how have post 1946 cycles differed from earlier cycles and what are the major factors that contribute to business cycles they extend their investigation in some areas as far back as 1875 to afford a deeper understanding of both economic history and the most recent economic fluctuations seven papers address specific aspects of economic activity consumption investment inventory change fiscal policy monetary behavior open economy and the labor market five papers focus on aggregate economic activity in a number of cases the papers present findings that challenge widely accepted models and assumptions in addition to its substantive findings the american business cycle includes an appendix containing both the first published history of the nber business cycle dating chronology and many previously unpublished historical data series

a rank dependent utility model of uncertain lifetime abstract in a continuous time life cycle model of consumption with an uncertain lifetime we use a non parametric specification of rank dependent utility theory to characterize the preferences of the agent we prove that time consistency holds for a subclass of probability weighting function providing the foundation for a constant rate of time preference that interacts multiplicatively with the hazard rate instead of additively as in the yaari 1965 seminal model we calibrate both models to explain the hump in the life cycle consumption and show that the multiplicative model is more robust

an evaluation of the life cycle effects of minimum pensions on retirement behavior in this paper we explore the effects of the minimum pension program on welfare and retirement in spain this is done with a stylized life cycle model which provides a convenient analytical characterization of optimal behavior we use data from the spanish social security to estimate the behavioral parameters of the model and then simulate the changes induced by the minimum pension in aggregate retirement patterns the impact is substantial there is a threefold increase in retirement at 60 the age of first entitlement with respect to the economy without minimum pensions and total early retirement before or at 60 is almost 50 larger copyright 2007 john wiley sons ltd

life cycle consumption and hyperbolic discount functions abstract studies of animal and human behavior suggest that discount functions are approximately hyperbolic ainslie picoeconomics 1992 hyperbolic models explain a wide range of empirical anomalies including 1 missing precautionary savings effects 2 incongruence between the elasticity of intertemporal substitution and the inverse of the coefficient of relative risk aversion 3 consumption discontinuities at retirement 4 variation in patience over the life cycle 5 consumer self reports of undersaving 6 disproportionate retirement accumulation in illiquid assets 7 asset specific marginal propensities to consume and 8 declining national savings rates in developed countries hyperbolic models also provide a new framework for analyzing the welfare gains that come from pro saving policies like social security and tax deferred retirement accounts

asymmetric adjustment costs in simple general equilibrium models abstract this paper demonstrates that the introduction of asymmetric adjustment costs in a simple general equilibrium framework establishes a meaningful link between factor price determination and output determination breaking the analytically convenient dichotomy of the heckscher ohlin samuelson model the possibility of trade between seemingly similar countries that differ in their adjustment technologies is visited

uncertain lifetime and intertemporal choice risk aversion as a rationale for time discounting this article makes explicit the links between preferences over lotteries on length of life and intertemporal choice it shows that the approach used by traditional life cycle models to account for uncertain survival corresponds to a strong assumption of risk neutrality with respect to length of life relaxing such an assumption leads us to develop a more general formulation of lifetime utility in which time discounting is directly related to preferences over length of life exponential and hyperbolic discounting are found to result in a first approximation from constant and hyperbolic risk aversion with respect to length of life

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

investability the key to competitive regions and cities this article proposes and develops a concept investability that can be used for analysing the competitive position of cities or regions and formulating policy responses it can be defined as conditions that are conducive to a higher level of investment and refers principally to the business environment in which economic agents operate the paper discusses various influences on investment decisions and how they will impinge on different classes of potential investors policy implications are developed and the ways in which the concept might be used in policy making are examined

the effects of tax increment financing on economic development abstract local governments attempt to influence business location decisions and economic development through use of the property tax tax increment financing tif earmarks property tax revenues that result from growth in assessed valuation the tif revenues are to be used for economic development projects but may also be diverted for other purposes using data for the chicago metropolitan area that includes information on property value growth before and after tif adoption we find evidence that cities that adopt tif grow more slowly than those that do not we test for and reject sample selection bias as an explanation of this finding

time tradeoff sequences for analyzing discounting and time inconsistency this paper introduces time tradeoff tto sequences as a general tool to analyze intertemporal choice we give several applications for empirical purposes we can measure discount functions without requiring any measurement of or assumption about utility we can quantitatively measure time inconsistencies and simplify their qualitative tests tto sequences can be administered and analyzed very easily using only pencil and paper for theoretical purposes we use tto sequences to axiomatize quasi hyperbolic discount functions we demonstrate the feasibility of measuring tto sequences in an experiment in which we tested the axiomatizations our findings suggest rejections of several currently popular discount functions and call for the development of new ones it is especially desirable that such discount functions can accommodate increasing impatience

compositional change aggregation and dynamic factor demand estimates on a panel of manufacturing firms most empirical research on investment and dynamic factor demand has used aggregated data the large number of authors who have cited this as a source of problems strongly suggests possible benefits from analyzing individual firm data this paper presents an analysis of a panel dataset of us manufacturing firms several models based on cost minimization and a three factor cobb douglas technology are developed the differences concern whether the technology varies across two digit sic industries the presence of fixed adjustment lags and the determinants of adjustment costs identification relies on the rational expectations hypothesis and estimation on non linear 3sls the estimates indicate that versions with the adjustment lag perform better than others conditional elasticities reveal that factor demand responds rapidly to anticipated changes in output and factor prices a finding consistent with other recent work it appears that the factor demand of large firms is more price sensitive and less sensitive to output than small firms consistent with recent work on credit market imperfections comparison of the results based on the pooled and the industry varying technologies indicate that the use of aggregate data is indeed a source of problems

on the public economics of annuities with differential mortality this paper studies the problem of redistribution between individuals having different mortality rates we use a continuous time model in which there are two types of individuals characterized by different survival probability paths individual preferences are represented by a generalized life cycle utility function which can exhibit temporal risk aversion we successively compare utilitarian allocations when individuals exhibit temporal risk neutrality and temporal risk aversion this problem is analyzed successively in the context of full information and asymmetric information on mortality rates

firm size and r d intensity a re examination using data from the federal trade commission s line of business program and survey measures of technological opportunity and appropriability conditions this paper finds that overall firm size has a very small statistically insignificant effect on business unit r d intensity when either fixed industry effects or measured industry characteristics are taken into account business unit size has no effect on the r d intensity of business units that perform r d but it affects the probability of conducting r d business unit and firm size jointly explain less than one per cent of the variance in r d industry effects explain nearly half the variance two sets of well known hypotheses are associated with the later work of joseph schumpeter the first concerns the effects of market concentration on research and development investment and on innovative performance the second bears on the effects of firm size on r d and innovation in a recent paper levin cohen and mowery 1985 we re examined the first set of hypotheses simple regressions at the line of business level replicated the established findings that both r d intensity and innovative performance first increase and then decrease as industrial concentration rises the effect of concentration however was sharply attenuated when we controlled for interindustry differences in technological opportunity and in the appropriability of returns from new technology our results suggested that it is probably unwarranted to conclude that market concentration favors r d investment and innovation in this paper we investigate the schumpeterian hypothesis that large size is conducive to r d investment this relationship has been studied at least as intensively as the link between concentration and r d but our approach is novel in two respects first using data collected by the federal trade

survival ambiguity and welfare abstract nearly all life cycle models adopt yaari s 1965 assumption that individuals know the survival probabilities that they face given that an individual s exact survival probabilities are likely unknown we explore the implications of relaxing this assumption if there is no annuity market then the welfare cost of survival ambiguity is large and regressive ambiguity neutral individuals would pay as much as 1 of total lifetime consumption for immediate resolution of ambiguity and the bottom income quintile is 4 times worse off than the top quintile alternatively with the availability of competitive annuity contracts survival ambiguity is welfare improving because it allows competitive insurance companies to pool risk across survival types even though social security and annuities share some properties social security does not help to hedge survival ambiguity

differential mortality and social security this paper studies the normative problem of redistribution between individuals who differ in their lifespans we discuss aspects related to the objective function and argue that aversion to multiperiod inequality should be taken into account then we study the properties of the social optimum both with full information and with asymmetric information we highlight the role of aversion to multiperiod inequality and show that it has substantial consequences on the design of social security schemes in particular we show that for a low resp high aversion to multiperiod inequality a negative resp positive implicit tax rate on continued activity is desirable

is there one unifying concept of utility an experimental comparison of utility under risk and utility over time the nature of utility is controversial whereas decision theory commonly assumes that utility is context specific applied and empirical decision analysis typically assumes one unifying concept of utility applicable to all decision problems this controversy has hardly been addressed empirically because of the absence of methods to measure utility outside the context of risk we introduce a method to measure utility over time and compare utility under risk and utility over time we distinguish between gains and losses and also measure loss aversion in two experiments we found that utility under risk and utility over time differed and were uncorrelated utility under risk was more curved than utility over time subjects were loss averse both for risk and for time but loss aversion was more pronounced for risk loss aversion over risk and time were uncorrelated this suggests that loss aversion although important in both decision contexts is volatile and subject to framing

negligible senescence an economic life cycle model for the future abstract we propose a model of aging and health deficit accumulation model with an infinite time horizon and a steady state of constant health the time of death is uncertain and endogenous to lifestyle and health behavior this setup can be conceptualized as a strive for immortality that is never reached we discuss adjustment dynamics and show that the new setup is particularly useful to understand aging of the oldest old i e of individuals for which morbidity and mortality have reached a plateau we then show how the existence of a steady state can be used to perform comparative dynamics exercises analytically as an illustration we investigate the effects of more expensive health investment and of advances in medical technology on optimal short run and long run health behavior

anomalies in intertemporal choice evidence and an interpretation research on decision making under uncertainly has been strongly influenced by the documentation of numerous expected utility eu anomalies behaviors that violate the expected utility axioms the relative lack of progress on the closely related topic of intertemporal choice is partly due to the absence of an analogous set of discounted utility du anomalies we enumerate a set of du anomalies analogous to the eu anomalies and propose a model that accounts for the anomalies as well as other intertemporal choice phenomena incompatible with du we discuss implications for savings behavior estimation of discount rates and choice framing effects

a simple explanation of some key time preference anomalies individual time discounting behaviour experimentally exhibits important anomalies that are inconsistent with the standard discounted utility model these include the time preference reversal characteristic of hyperbolic discounting the magnitude effect and the extreme sign effect i propose a simple explanation of discounting that accounts for these three anomalies simultaneously within the context of the expected utility model with uncertainty risk aversion and preference for precautionary saving experimentalement le comportement individuel dans l escompte du temps revele des anomalies importantes qui cadrent mal avec le modele standard de l utilite anticipee ce sont par exemple le renversement de la preference temporelle qui caracterise le processus d escompte hyperbolique ou l effet de magnitude ou l effet de signe extr me on propose une explication simple du comportement d escompte qui explique simultanement ces trois anomalies dans le cadre du modele d utilite anticipee en presence d incertitude d aversion au risque et de preference pour l epargne de precaution

magnitude time and risk differ similarly between joint and single evaluations arguably all choice options involve three basic attributes magnitude outcome size time of occurrence and probability of occurrence and are evaluated in one of two basic evaluation modes je joint evaluation involving comparison of multiple options and se single evaluation without comparison this research explores how reactions to the three basic attributes and their associated functions utility time discounting and probability weighting vary between the two basic evaluation modes nine studies tapping diverse contexts yield two general results first for all these attributes people are more sensitive to variations near endpoints zero magnitude no delay and 0 or 100 probability than in other regions and this differential sensitivity is more pronounced in se than in je second when faced with options involving a trade off between magnitude and time delay or between magnitude and probability risk people are both more delay averse and more risk averse in se than in je

a note on the econometric use of constant dollar inventory series abstract one dollar of finished goods inventories does not represent the same amount of physical goods as one dollar of sales when department of commerce constant dollar series are used this can cause seriously biased regression estimates

sustainability and the anchoring of capital negotiations surrounding two major urban projects in switzerland theurillat t and crevoisier o sustainability and the anchoring of capital negotiations surrounding two major urban projects in switzerland regional studies this article deals with the anchoring of mobile financial capital in the city and urban sustainability illustrated by a case study in the swiss context it develops the theory that new forms of negotiation are appearing around urban projects development construction firms are playing a central role they are capable of evaluating and translating the multiple dimensions of a project and certain sustainability challenges into financial terms in a way that permits the anchoring of capital in the city in parallel the issue of sustainability depends greatly on the capacity of the local actors to negotiate with the promoters of urban projects

the individual life cycle annuity market imperfections and economic growth we study the effects of an annuity market imperfection on individual agents life cycle decisions and on the macroeconomic growth rate in an overlapping generations model with single sector endogenous growth our model features both age dependent mortality and labour productivity we model imperfect annuities by introducing a load factor on the annuity rate faced by finitely lived agents our main finding is that annuity market imperfections decrease economic growth because less assets are necessary for consumption late in life in addition we find that both the quantitative and qualitative effects of annuity market imperfections are grossly overestimated in a partial equilibrium analysis because it disregards general equilibrium repercussions

urban regeneration and the development industry healey p 1991 urban regeneration and the development industry reg studies 25 97 108 this paper examines a key assumption of urban policy in britain in the 1980s this assumption is that urba

does chicago s tax increment financing tif programme pass the but for test job creation and economic development impacts using time series data chicago uses tax increment financing tif to promote economic development to a greater extent than any other large american city this paper conducts a comprehensive assessment of the effectiveness of chicago s tif programme in creating economic opportunities and catalysing real estate investments at the neighbourhood scale this paper uses a unique panel dataset at the block group level to analyse the impact of tif designation and investments on employment change business creation and building permit activity after controlling for potential selection bias in tif assignment this paper shows that tif ultimately fails the but for test and shows no evidence of increasing tangible economic development benefits for local residents implications for policy are considered

firm heterogeneity internal finance and credit rationing this paper assesses the role of internal net worth holding constant investment opportunities in the allocation of credit in the presence of asymmetric information in the capital market the authors consider an economy in which both symmetric information and information intensive entrepreneurs seek funds from the capital market and they develop a simple general equilibrium model of credit allocation their emphasis is on shocks to borrower net worth depending on levels of net worth the symmetric information allocation a credit collapse or intermediate allocations are possible the model yields predictions corresponding to accelerator effects on investment and output as well as real effects of collateral redistributions copyright 1990 by royal economic society

value functions for infinite period planning cost benefit and risk analysis studies that model tradeoffs between the present and the distant future by means of present value discounting have been criticized for according the future and thus future generations far too little importance this paper presents an alternative means of modeling tradeoffs between different periods that accords the future far more importance than present value discounting and that is no more difficult to apply the paper also presents a means of modeling the preference issue of concern for equity or stability between different periods

providing cheap land for social housing breaching the state aid regulations of the single european market tasan kok t groetelaers d a haffner m e a van der heijden h m h and korthals altes w k providing cheap land for social housing breaching the state aid regulations of the single european market regional studies european union member states are not permitted to provide aid that will distort competition by favouring certain undertakings or the production of certain goods which may then undermine trading in the european market this prohibition also affects government authorities that are willing to provide cheap land for social and affordable housing this paper reviews the ways in which land is provided for social housing in the netherlands and explores possibilities for reshaping current practices to make them compatible with the regime of the single european market tasan kok t groetelaers d a haffner m e a van der heijden h m h and korthals altes w k

investment gestation lags the difference between time to build and delivery lags the timing of investment and capital stock accumulation can differ as a result of time to build and or delivery lags in this paper simple calibration methods are used to illustrate the differences in these sources of gestation lags

optimal pollution abatement under sustainable and other social time preferences this paper analyses optimal pollution abatement expenditure and the pricing of pollution under alternative social time preferences including sustainable preferences defined as those that are consistent with two axioms of sustainable development introduced by chichilnisky land econ 73 467 491 1997 these axioms state essentially that neither the welfare of present nor future generations ought to be favoured over the other in determining the socially optimal path of economic development the method is to calibrate a modified ramsey model of optimal global growth and saving where pollution is generated by the global output of goods and services pollution in turn reduces output the simulation results illustrate how sensitive the optimal pollution price and abatement expenditure can be over time to assumptions about the social time preference rate they also show that sustainable preferences impose a lower burden on future generations in terms of the pollution price and abatement expenditure hence there is a case for governments to make explicit their value judgments about intergenerational welfare in the context of their notion of sustainable development when setting target pollution abatement levels and pollution prices over time

retirement spending and biological age abstract we solve a lifecycle model in which the consumer s chronological age does not move in lockstep with calendar time instead biological age increases at a stochastic non linear rate in time like a broken clock that might occasionally move backwards in other words biological age could actually decline our paper is inspired by the growing body of medical literature that has identified biomarkers which indicate how people age at different rates this offers better estimates of expected remaining lifetime and future mortality rates it isn t farfetched to argue that in the not too distant future personal age will be more closely associated with biological vs calendar age thus after introducing our stochastic mortality model we derive optimal consumption rates in a classic yaari 1965 framework adjusted to our proper clock time in addition to the normative implications of having access to biological age our positive objective is to partially explain the cross sectional heterogeneity in retirement spending rates at any given chronological age in sum we argue that neither biological nor chronological age alone is a sufficient statistic for making economic decisions rather both ages are required to behave rationally

strotz meets allais diminishing impatience and the certainty effect abstract decision makers tend to exhibit a higher degree of impatience when considering a delay to an immediate reward than when contemplating an identical delay to an equal future reward this work argues that diminishing impatience originates from the distinction between the certain present and the risky future a simple functional representation of preferences exhibiting time inconsistency when the future is uncertain is derived experimental evidence which is inconsistent with other formulations that account for diminishing impatience supports the proposed approach the new theory uncovers a tight relation between diminishing impatience and well known behavioral regularities in choice under risk and uncertainty jel d12 d81

business cycles and the relationship between concentration and price cost margins using a newly constructed panel data base we examine changes in price cost margins in 284 manufacturing industries between 1958 and 1981 a key finding is a dramatic narrowing of the spread between the margins of concentrated and unconcentrated industries over this period we provide evidence that this narrowing is a result of the greater sensitivity of price cost margins in more concentrated industries to demand fluctuations this finding is robust to the inclusion of other industry variables and to measures of import competition the results indicate that cross sectional estimates of the concentration margins relationship are likely to be both biased and misleading

life cycle preferences revisited an axiomatic construction for life cycle preferences accounting for the finiteness and the randomness of life duration is provided we emphasize the role of intertemporal correlation aversion and explain why multiplicative preferences provide an interesting alternative to additive preferences allowing risk aversion and intertemporal elasticity of substitution to be separated implications regarding the shape of the optimal consumption profiles are discussed

simple tests of distributional effects on macroeconomic equations the presence of distributional effects in macroeconomic equations is shown to coincide with nonlinearity in micro behavioral relationships parameters estimated with aggregate data as in representative agent models contain distributional biases that are not measurable using aggregate data alone tests for distributional effects and other measures of the extent of aggregation problems are derived using distributional data observed over time significant distributional effects are noted for a model of annual aggregate u s commodity expenditure data a static model that accommodates individual heterogeneity is found to be statistically equivalent to a simply dynamic model that accommodates first order autocorrelation

risk aversion and the value of life we show that state non separable preferences a la epstein zin weil ezw provide a tractable and flexible framework to study the economics of health and longevity this utility representation 1 admits a preference for timing of resolution of uncertainty regarding mortality risks 2 links the marginal valuation of survival to the level of survival 3 can preserve homotheticity even for low degrees of intertemporal substitution without generating implausible predictions regarding the value of life and 4 adds needed flexibility to account for the empirical evidence on the value of life we illustrate the implications of ezw preferences for the economic value of observed differences in life expectancy across countries and over time and for the value of life over the life cycle

comparative risk aversion a formal approach with applications to saving behavior we consider a formal approach to comparative risk aversion and applies it to intertemporal choice models this allows us to ask whether standard classes of utility functions such as those inspired by kihlstrom and mirman 1974 selden 1978 epstein and zin 1989 and quiggin 1982 are well ordered in terms of risk aversion moreover opting for this model free approach allows us to establish new general results on the impact of risk aversion on savings behaviors in particular we show that risk aversion enhances precautionary savings clarifying the link that exists between the notions of prudence and risk aversion

the own wage elasticity of labor demand a meta regression analysis firms labor demand responses to wage changes are of key interest in empirical research and policy analysis however despite extensive research estimates of labor demand elasticities remain subject to considerable heterogeneity in this paper we conduct a comprehensive meta regression analysis to re assess the empirical literature on labor demand elasticities building on 942 elasticity estimates from 105 different studies we identify sources of variation in the absolute value of this elasticity heterogeneity due to the theoretical and empirical specification of the labor demand model different datasets used or sectors and countries considered explains more than 80 of the variation in the estimates we further find substantial evidence for the presence of publication selection bias as estimates of the own wage elasticity of labor demand are upwardly inflated

accidental bequests a curse for the rich and a boon for the poor when accidental bequests signal otherwise unobservable individual characteristics such as productivity and longevity the population should be partitioned into two groups those who do not receive an inheritance and those who do the first tagged group receives a mirrlees second best tax schedule the second group when its type is fully revealed faces a first best tax schedule receiving an inheritance makes high ability types worse off and low ability types better off high ability individuals face a bequest tax of more than 100 percent while low ability types face a bequest tax that can be smaller as well as larger than 100 percent and it might even be negative

the multivariate flexible accelerator model its empirical restrictions and an application to u s manufacturing this paper derives an exhaustive set of restrictions implied by the multistock flexible accelerator specification of the adjustment cost model for the firm the flexible accelerator specification of the demand for capital and labor is estimated using u s manufacturing annual data for the 1947 1976 period the consistency of the data with the model is examined by testing the validity of the derived restrictions finally the conditions which permit aggregation over firms are determined and tested empirically the flexible accelerator specification has been popular in the empirical literature on interrelated investment and employment decisions see nadiri and rosen 38 coen and hickman 10 and schramm 40 more recent examples include sargent 39 berndt fuss and wavermann 4 berndt and morrison 6 and meese 34 under suitable assumptions the specification may be rationalized by the adjustment cost model of the firm eisner and strotz 13 lucas 30 mortensen 35 extends the work of lucas and derives some empirically testable restrictions of the accelerator specification that are implied by the adjustment cost framework the broad objective of this paper is to provide a more rigorous and comprehensive test of the adjustment cost model than is presently found in the literature this objective is achieved in three stages first we offer an alternative derivation of the mortensen restrictions and more importantly we prove theorem 1 that his restrictions are exhaustive i e we establish an integrability result for the flexible accelerator adjustment cost model second the flexible accelerator specification of the demand for capital and labor is estimated using total u s manufacturing annual data for the 1947 76 period it is assumed that firms minimize expected production costs subject to a technology which implies that capital and labor stocks are costly to adjust while a third factor materials is freely adjustable the consistency of the data with the adjustmentcost framework is examined by testing for the validity of the derived restrictions further we test the validity of some separability restrictions on the adjustmentcost technology that to varying degrees are imposed a priori in all of the cited empirical studies finally we provide a complete characterization of the individual firm technologies which justify the common assumption of the existence of a representative firm this problem of aggregation over firms which has been

a note on longevity enhancing investment we argue that risk averse individuals prefer to increase their longevity in the direction of rectangularization of the survival curve instead of an upward shift of that curve risk aversion is measured by the concept of fear of ruin

models as usual for unusual risks on the value of catastrophic climate change we study the role of alternative intertemporal preference representations in a model of economic growth stock pollutant and endogenous risk of catastrophic collapse we contrast the traditional discounted utility model which assumes risk neutrality with respect to intertemporal utility with a multiplicative choice model that displays risk aversion in that dimension first we show that both representations of preferences can rationalize the same business as usual economy for a given interest rate and no pollution externality second once we introduce a collapse risk whose hazard rate is a function of the pollution stock multiplicative preferences recommend a much more stringent policy response an illustration in the context of climate change indicates that switching to the multiplicative preference representation has a similar effect in terms of policy recommendations as scaling up the schedule of the hazard rate by a factor of 100

health and other asset holdings despite clear evidence of correlations between financial and medical statuses and decisions most models treat financial and health related choices separately this article bridges this gap by proposing a tractable dynamic framework for the joint determination of optimal consumption portfolio holdings health investment and health insurance we solve for the optimal rules in closed form and capitalize on this tractability to gain a better understanding of the conditions under which separation between financial and health related decisions is sensible and of the pathways through which wealth and health determine allocations welfare and other variables of interest such as expected longevity or the value of health furthermore we show that the model is consistent with the observed patterns of individual allocations and provide realistic estimates of the parameters that confirm the relevance of all the main characteristics of the model

dynamic factor demands and the effects of energy price shocks a dynamic model is used to understand how sharp changes in energy prices affect investment behavior employment and energy use the authors discuss the theory behind their model selection model specifications estimation methods and data list parameter estimates and elasticities for the selected model and describe the simulations they conclude that 1 the data strongly reject the hypothesis of constant returns to scale within their specification of aggregate production 2 the data indicate adjustment costs on labor are small and 3 their results help reconcile some of the conflicting estimates of energy demand elasticities appearing in recent literature 23 references 3 figures 3 tables

risk and preference reversals in intertemporal choice abstract this paper argues that observations of non stationary choice behavior need not necessarily imply specific properties of the individual s discount function as we show the observed preference reversals in intertemporal choice are consistent with constant discounting and can alternatively be explained by decreasing absolute risk aversion together with the individual s risk perception this risk may concern the size of the actual outcome or the endowment consumption stream to which the outcome is added both types of uncertainty naturally appear in the context of intertemporal choice we show how relative degrees of changes in risk over time can determine choices

financing property s contribution to regeneration attracting investment and finance into inner city and other renewal areas poses particular difficulties and is frequently reliant on strong public sector commitment through special incentives or other mechanisms to provide the conditions to lever private sector activity this paper initially links the concept of market failure and the rationale for regeneration and examines policy responses from uk european and us perspectives followed by a consideration of public and private sector financing approaches international perspectives draw particularly upon the use of tax based mechanisms in regeneration notably those used in the us in the european context the paper highlights implications for regeneration stemming from the interpretation of state aid rules and competition policy conclusions reflect upon the complexity of regeneration and the importance of the different stakeholders within the regeneration process

labor and investment demand at the firm level a comparison of french german and u s manufacturing 1970 79 we investigate how labor and investment demand at the firm level gross as well as net and replacement investment separately differs in french german and u s manufacturing and has changed since the 1974 75 crisis we use three consistent panel data samples of large firms for 1970 79 and rely on simple models of the accelerator profits type we find that the accelarator effects and the profits effects did not vary much between 1970 73 and 1976 79 and were quite comparable in the three countries the former being of a more permanent nature and the latter more transitory to a large extent these effects account for the important changes and differences in labor and investment demand between the two subperiods and across the three countries

do markets differ much this essay reports the results of a crosssection study of differences in accounting profitability that sheds light on some basic controversies in industrial economics most previous cross section studies in this field have been concerned with testing hypotheses about structural coefficients in models meant to apply to essentially all markets as we have learned more about the difficulties of constructing such general models and of performing tests on their structural parameters properly structural cross section analysis has fallen out of fashion in contrast to most of the cross section literature the analysis reported here is fundamentally descriptive it does not attempt directly to estimate or to test hypotheses about structural parameters i hope to show by example that one can perform illuminating analysis of cross section data without a host of controversial maintained hypotheses cross section data can yield interesting stylized facts to guide both general theorizing and empirical analysis of specific industries even if they cannot easily support full blown structural estimation one can view the sort of search for stylized facts conducted here as either a replacement for or an input to interindustry structural estimation depending on one s feeling about the long run potential of that research approach this study also departs from much of the cross section literature by being fundamentally concerned with the importance of various effects not just with coefficient signs and t statistics in particular this essay provides estimates of the relative importance of firm market and market share differences in the determination of business unit divisional profitability in u s manufacturing using 1975 data from the line of business program of the u s federal trade commission ftc i find support neither for the existence of firm effects nor for the importance of market share effects moreover while industry effects apparently exist and are important they appear to be negatively correlated with seller concentration in these data section i relates firm market and share effects to current issues and controversies in industrial economics and thus supplies the motivation for our empirical analysis the remainder of the essay treats the data and

beyond demand and supply curves in macroeconomics this paper surveys recent issues in macroeconomics from the viewpoint of dynamic economic theory the need to look beyond demand and supply curves and the insights that come from doing so are emphasized examples of issues in debt management and fiscal policy are analyzed

the welfare value of fda s mercury in fish advisory a dynamic reanalysis assessing the welfare impact of consumer health advisories is a thorny task recently shimshack and ward 2010 studied how u s households responded to fda s 2001 mercury in fish advisory they found that the average at risk household reduced fish consumption by 21 resulting in a 17 reduction in mercury exposure at the cost of a 21 reduction in cardioprotective omega 3 fatty acids based on a static assessment of the health costs and benefits shimshack and ward concluded that the advisory policy resulted in an overall consumer welfare loss in this note we propose a dynamic assessment that links the long term cardiovascular health effects of the advisory to life cycle consumption we find that under reasonable assumptions the welfare loss might be much larger than suggested our analysis highlights the importance of accounting for dynamic effects when evaluating persistent changes in exposure to environmental health risks

longevity genes and efforts an optimal taxation approach to prevention this paper applies the analytical tools of optimal taxation theory to the design of the optimal subsidy on preventive behaviours in an economy where longevity varies across agents and depends on preventive expenditures and on longevity genes public intervention can be here justified on three grounds corrections for misperceptions of the survival process and for externalities related to individual preventive behaviour and redistribution across both earnings and genetic dimensions the optimal subsidy on preventive expenditures is shown to depend on the combined impacts of misperception externalities and self selection it is generally optimal to subsidize preventive efforts to an extent depending on the degree of individual myopia on how productivity and genes are correlated and on the complementarity of genes and preventive efforts in the survival function

aggressive oil extraction and precautionary saving coping with volatility the effects of stochastic oil demand on optimal oil extraction paths and tax spending and government debt policies are analyzed when the oil demand schedule is linear and preferences quadratic without prudence optimal oil extraction is governed by the hotelling rule and optimal budgetary policies by the tax and consumption smoothing principle volatile oil demand brings forward oil extraction and induces a bigger government surplus with prudence the government depletes oil reserves even more aggressively and engages in additional precautionary saving financed by postponing spending and bringing taxes forward especially if it has substantial monopoly power on the oil market gives high priority to the public spending target is very prudent and future oil demand has high variance uncertain economic prospects induce even higher precautionary saving and if non oil revenue shocks and oil revenue shocks are positively correlated even more aggressive oil extraction in contrast prudent governments deliberately underestimate oil reserves which induce less aggressive oil depletion and less government saving but less so if uncertainty about reserves and oil demand are positively correlated

the existence uniqueness and optimality of the terminal wealth depletion time in life cycle models of saving under uncertain lifetime and borrowing constraint abstract in life cycle models of saving under uncertain lifetime and borrowing constraint the consumer s wealth must be depleted before the maximum lifetime this paper investigates the existence uniqueness and optimality of the terminal wealth depletion time it is proved that the optimal terminal wealth depletion time if such exists must be unique if the equation that determines the optimal terminal wealth depletion has multiple solutions then the location of the optimal solution will depend on the configuration of the solutions an optimality test is developed to verify whether a candidate solution for the terminal wealth depletion time is indeed optimal the paper introduces a method new to economics the dubovitskii milyutin adjoint equation to analyze the properties of the optimal control problem