interpreting the great moderation changes in the volatility of economic activity at the macro and micro levels most advanced economies have experienced a striking decline in the volatility of aggregate economic activity since the early 1980s volatility reductions are evident for output and employment at the aggregate level and across most industrial sectors and expenditure categories inflation and inflation volatility have also declined dramatically previous studies offer several potential explanations for this great moderation we review evidence on the great moderation in conjunction with evidence about volatility trends at the micro level we combine the two types of evidence to develop a tentative story for important components of the aggregate volatility decline and its consequences the key ingredients are declines in firm level volatility and aggregate volatility most dramatically in the durable goods sector surprisingly this has occurred without a decline in household consumption volatility and individual earnings uncertainty our explanation for the aggregate volatility decline stresses improved supply chain management particularly in the durable goods sector and less important a shift in production and employment from goods to services we provide evidence that better inventory control made a substantial contribution to declines in firm level and aggregate volatility consistent with this view if we look past the turbulent 1970s and early 1980s much of the moderation reflects a decline in high frequency short term fluctuations while these developments represent efficiency gains they do not imply nor is there evidence for a reduction in economic uncertainty faced by individuals and households

option pricing when the variance changes randomly theory estimation and an application in this paper we examine the pricing of european call options on stocks that have vari ance rates that change randomly we study continuous time diffusion processes for the stock return and the standard deviation parameter and we find that one must use the stock and two options to form a riskless hedge the riskless hedge does not lead to a unique option pricing function because the random standard deviation is not a traded security one must appeal to an equilibrium asset pricing model to derive a unique option pricing function in general the option price depends on the risk premium associated with the random standard deviation we find that the problem can be simplified by assuming that volatility risk can be diversified away and that changes in volatility are uncorrelated with the stock return the resulting solution is an integral ofthe black scholes formula and the distribution function for the variance of the stock price we show that accurate option prices can be computed via monte carlo simulations and we apply the model to a set of actual prices

erratum to why has u s inflation become harder to forecast the article journal of money credit and banking supplement to vol 39 no 1 february 2007 contains errors in figures 2 4 and tables 4 5 associated with a coding error in our program for estimating the uc sv model we thank ling hu of platinum grove asset management for finding this error and bringing it to our attention the corrected uc sv rows for tables 4 and 5 are given below corrected versions of figures 2 4 and corrected replication files can be found at http www princeton edu mwatson

models of stock returns a comparison in this paper a discrete mixture of normal distributions is proposed to explain the observed significant kurtosis fat tails and significant positive skewness in the distribution of daily rates of returns for a sample of common stocks and indexes stationarity tests on the parameter estimates of this discrete mixture of normal distributions model revealed significant differences in the mean estimates that can explain the observed skewness and significant differences in the variance estimates that can explain the observed kurtosis an alternative explanation for the observed fat tails is the symmetric student model the result of a comparison between the models is that the discrete mixture of normal distributions model has substantially more descriptive validity than the student model for many years both financial economists and statisticians have been concerned with the description of stock market returns the form of the distribution of stock returns is a crucial assumption for mean variance portfolio theory theoretical models of capital asset prices and the prices of contingent claims for example understanding the behavior of the variance is essential to option pricing models empirical tests of asset pricing models and the efficient markets hypothesis draw statistical inferences that are also conditional on distributional assumptions the most convenient assumption for financial theory and empirical methods is that the distribution of security rates of return be multivariate normal with parameters that are stationary over time since the normal distribution is stable under addition any arbitrary portfolio of stocks will also be normally distributed with the additional assumption of risk aversion mean variance theory follows furthermore the assumptions of normality and parameter stationarity are required for most of the econometric techniques typically used in empirical research tests of the normality hypothesis on the daily returns of the dow jones industrial stocks by fama 121 revealed more kurtosis fatter tails than that predicted from a sample of independent and identically distributed normal variates fama concluded from this evidence that the distribution of price changes conforms better to the stable paretian distribution with characteristic exponent

the pricing of options on assets with stochastic volatilities one option pricing problem that has hitherto been unsolved is the pricing of a european call on an asset that has a stochastic volatility this paper examines this problem the option price is determined in series form for the case in which the stochastic volatility is independent of the stock price numerical solutions are also produced for the case in which the volatility is correlated with the stock price it is found that the black scholes price frequently overprices options and that the degree of overpricing increases with the time to maturity one option pricing problem that has hitherto remained unsolved is the pricing of a european call on a stock that has a stochastic volatility from the work of merton 12 garman 6 and cox ingersoll and ross 3 the differential equation that the option must satisfy is known the solution of this differential equation is independent of risk preferences if a the volatility is a traded asset or b the volatility is uncorrelated with aggregate consumption if either of these conditions holds the risk neutral valuation arguments of cox and ross 4 can be used in a straightfoward way this paper produces a solution in series form for the situation in which the stock price is instantaneously uncorrelated with the volatility we do not assume that the volatility is a traded asset also a constant correlation between the instantaneous rate of change of the volatility and the rate of change of aggregate consumption can be accommodated the option price is lower than the blackscholes b s 1 price when the option is close to being at the money and higher when it is deep in or deep out of the money the exercise prices for which overpricing by b s takes place are within about ten percent of the security price this is the range of exercise prices over which most option trading takes place so we may in general expect the b s price to overprice options this effect is exaggerated as the time to maturity increases one of the most surprising implications of this is that if the b s equation is used to determine the implied volatility of a near the money option the longer the time to maturity the lower the implied volatility numerical solutions for the case in which the volatility is correlated with the stock price are also examined the stochastic volatility problem has been examined by merton 13 geske 7 johnson 10 johnson and shanno 11 eisenberg 5 wiggins 16 and

why has u s inflation become harder to forecast we examine whether the u s rate of price inflation has become harder to forecast and to the extent that it has what changes in the inflation process have made it so the main finding is that the univariate inflation process is well described by an unobserved component trend cycle model with stochastic volatility or equivalently an integrated moving average process with time varying parameters this model explains a variety of recent univariate inflation forecasting puzzles and begins to explain some multivariate inflation forecasting puzzles as well

the role of credit in the great moderation a multivariate garch approach abstract during the great moderation financial innovation in the us increased the size and scope of credit flows supporting the growth of wealth we hypothesize that spending out of wealth came to finance a wider range of gdp components such that it smoothed gdp both these trends combined would be consistent with a decrease in the volatility of output we suggest testable implications in terms of both growth of credit and output and volatility of growth in a multivariate garch framework we test this view for home mortgages and residential investment we observe unidirectional causality in variance from total output residential investment and non residential output to mortgage lending before but not during the great moderation these findings are consistent with a role for credit dynamics in explaining the great moderation

trade finance specialization and synchronization i investigate the determinants of business cycle synchronization across regions the linkages between trade in goods financial openness specialization and business cycle synchronization are evaluated in the context of a system of simultaneous equations the main results are as follows i specialization patterns have a sizable effect on business cycles most of this effect is independent of trade or financial policy but directly reflects differences in gdp per capita ii a variety of measures of financial integration suggest that economic regions with strong financial links are significantly more synchronized even though they also tend to be more specialized iii the estimated role of trade is closer to that implied by existing models once intra industry trade is held constant the results obtain in a variety of data sets measurement strategies and specifications they relate to a recent strand of international business cycle models with incomplete markets and transport costs and on the empir

jump risks and the intertemporal capital asset pricing model the specification of the stochastic process for stock prices is an important assumption underlying most equilibrium and option pricing models in modern finance this is particularly true of the continuous time capital asset pricing models where it is assumed that asset prices follow diffusion processes with continuous sample paths see merton 1973a breeden 1979 grossman and shiller 1982 the extent to which the implications of these models generalize to discontinuous sample paths is an unanswered question in theoretical finance however the answer to this question is of more than just theoretical interest since accumulated empirical evidence appears to be inconsistent with the continuous sample path assumption see rosenberg 1972 oldfield rogalski and jarrow 1977 rosenfeld 1982 one purpose of this paper is to provide some answers to this question we do this by extending merton s 1973a intertemporal asset pricing model in the special case of a constant investment opportunity set to include discontinuous sample paths for asset prices the constant investment opportunity set assumption is imposed because we are interested in obtaining sufficient conditions under which an instantaneous capital asset pricing model capm results the extension of our model to a stochastic opportunity set is discussed briefly in the text this paper investigates an economy where stock prices follow a jump diffusion process the first part of the analysis derives a sufficient condition under which an instantaneous capm will characterize equilibrium expected returns the sufficient condition is that the jump component of a stock s return must be unsystematic and diversifiable in the market portfolio the second part of the paper is an empirical investigation of the satisfaction of this condition the evidence is seen to be inconsistent with the satisfaction of this hypothesis that is the market portfolio appears to contain a jump component

openness and wage inequality in developing countries the latin american challenge to east asian conventional wisdom the experience of east asia in the 1960s and 1970s supports the theory that greater openness to trade tends to narrow the wage gap between skilled and unskilled workers in developing countries in latin america since the mid 1980s however increased openness has widened wage differentials this conflict of evidence is probably not the result of differences between east asia and latin america instead the conflict is probably the result of differences between the 1960s and the 1980s specifically the entry of china into the world market and perhaps the advent of new technology biased against unskilled workers

manufactured exports from developing countries and their terms of trade a reexamination of the sarkar singer results abstract sarkar and singer 1991 argue that the terms of trade for exports of manufactures from developing countries dcs like that for their primary commodity exports have manifested a long term trend favoring the importing developed countries we contend here that the authors have not paid adequate attention to appropriately adjusting the data and that they have misinterpreted the results when these limitations are taken into account a sound basis exists for the conclusion that through rapid expansion of manufactured exports dcs as a group have achieved significant gains in import purchasing power without generating adverse impact on the net barter terms of trade

macroeconomic forecasting and structural change the aim of this paper is to assess whether explicitly modeling structural change increases the accuracy of macroeconomic forecasts we produce real time out of sample forecasts for inflation the unemployment rate and the interest rate using a time varying coefficients var with stochastic volatility tv var for the us the model generates accurate predictions for the three variables in particular for inflation the tv var outperforms in terms of mean square forecast error all the competing models fixed coefficients vars time varying ars and the na ove random walk model these results are also shown to hold over the period commonly referred to as the great moderation

on jumps in common stock prices and their impact on call option pricing the black scholes call option pricing model exhibits systematic empirical biases the merton call option pricing model which explicitly admits jumps in the underlying security return process may potentially eliminate these biases we provide statistical evidence consistent with the existence of lognormally distributed jumps in a majority of the daily returns of a sample of nyse listed common stocks however we find no operationally significant differences between the black scholes and merton model prices of the call options written on the sampled common stocks

great moderation and great recession from plain sailing to stormy seas many have argued that the great recession of 2008 marks the end of the great moderation of the eighties and nineties this paper shows this is not the case through painstaking empirical analysis of the data output volatility remains subdued despite the tumult created by the great recession this nding has important implications for policymaking since a lower volatility of output the hallmark of the great moderation is associated with lower recoveries jel classication c22 e32

measuring uncertainty and its impact on the economy we propose a new framework for measuring uncertainty and its effects on the economy based on a large var model with errors whose stochastic volatility is driven by two common unobservable factors representing aggregate macroeconomic and financial uncertainty the uncertainty measures can also influence the levels of the variables so that contrary to most existing measures ours reflect changes in both the conditional mean and volatility of the variables and their impact on the economy can be assessed within the same framework moreover identification of the uncertainty shocks is simplified with respect to standard var based analysis in line with the favar approach and with heteroskedasticity based identification finally the model which is also applicable in other contexts is estimated with a new bayesian algorithm which is computationally efficient and allows for jointly modeling many variables while previous var models with stochastic volatility could only handle a handful of variables empirically we apply the method to estimate uncertainty and its effects using us data finding that there is indeed substantial commonality in uncertainty sizable effects of uncertainty on key macroeconomic and financial variables with responses in line with economic theory

are external shocks responsible for the instability of output in low income countries external shocks such as commodity price fluctuations natural disasters and the role of the international economy are often blamed for the poor economic performance of low income countries the author quantifies the impact of these different external shocks using a panel vector autoregression var approach and compares their relative contributions to output volatility in low income countries vis a vis internal factors he finds that external shocks can only explain a small fraction of the output variance of a typical low income country internal factors are the main source of fluctuations from a quantitative perspective the output effect of external shocks is typically small in absolute terms but significant relative to the historic performance of these countries

stock price distributions with stochastic volatility an analytic approach we study the stock price distributions that arise when prices follow a diffusion process with a stochastically varying volatility parameter we use analytic techniques to derive an explicit closed form solution for the case where volatility is driven by an arithmetic ornstein ublenbeck or ar1 process we then apply our results to two related problems in the finance literature 1 options pricing in a world of stochastic volatility and 2 the relationship between stochastic volatility and the nature of fat tailes in stock price distributions article published by oxford university press on behalf of the society for financial studies in its journal the review of financial studies

the emergence of regional business cycle in africa a reality or myth a bayesian dynamic factor model analysis this paper examines the evolution and the underlying forces of the business cycle co movements among seven african a 7 countries over the period 1970 2016 these countries accounted for over 60 of regional gdp have abundant natural resources access to the global capital market and widely viewed as potential drivers of regional or african business cycle we model the national business cycle using real output consumption and investment we employ a dynamic factor model to decompose fluctuations in these macro variables into a regional country specific and idiosyncratic components using bayesian methods we also analyse the relative importance of some notable drivers of business cycle fluctuations found in the literature we find that the idiosyncratic component is dominating cyclical fluctuations in the a 7 countries while country specific and regional factors play a negligible role suggesting the inexistence of a common regional cycle despite deepening intra african trade among the driving variables the terms of trade shocks exert greater influence on the a 7 business cycle while exchange rate movements and changes in money supply explain sizeable fluctuations in consumption and investment in most of the a 7 countries shocks associated with changes in relative domestic oil prices monetary and fiscal policies cause large output fluctuations

business cycle stylized facts and inventory behaviour new evidence for the euro area abstract the purpose of this paper is for the first time to use business tendency survey data first to identify new facts that are useful for the interpretation of the decline in the volatility of real activity in the euro area and second to test the inventory management hypothesis as an explanation for the great moderation in europe we present stylized facts from the business tendency data on series for inventories current production current orders and expected production for the euro area emphasizing the decline in the volatility of the series further we investigate whether the decline in inventory volatility can be attributed to an endogenous change in the persistence of shocks to the accumulation dynamics of inventories or to an exogenous change in the shocks hitting the inventory optimisation process our results at euro level generally indicate that there is no evidence of a break in the inventory accumulation process on the contrary the impact of exogenous shocks on inventory volatility appears to be steadily declining over time beginning from the mid 1980s

dynamic asset pricing theory with uncertain time horizon abstract this paper addresses the problem of pricing and hedging a random cash flow received at a random date in a general setup with a random time that is not a stopping time of the filtration generated by asset prices we first provide an explicit characterization of the set of equivalent martingale measures we also present price bounds consistent with perfect replication in the absence of arbitrage as is often the case such bounds are too wide to be of any practical use and we consider several choices for narrowing down to one the number of equivalent martingale measures

facts and challenges from the great recession for forecasting and macroeconomic modeling this paper provides a survey of business cycle facts updated to take account of recent data emphasis is given to the great recession which was unlike most other postwar recessions in the united states in being driven by deleveraging and financial market factors we document how recessions with financial market origins are different from those driven by supply or monetary policy shocks this helps explain why economic models and predictors that work well at some times do poorly at other times we discuss challenges for forecasters and empirical researchers in light of the updated business cycle facts

explaining the great moderation it is not the shocks this paper shows that the explanation of the decline in the volatility of gdp growth since the mid eighties is not the decline in the volatility of exogenous shocks but rather a change in their propagation mechanism

in memoriam on the death of the market mechanism the concept of the market mechanism emerged in the 1940s as a central feature in the thinking of the economics profession in the united states with improved knowledge of the scientific laws of the market economists argued that society could use the instrument of the market to achieve a wide range of social goals with maximal efficiency and effectiveness for example many economists have argued that the reduction of poverty is best accomplished by manipulating the labor market through the negative income tax or other technical devices health care other economists have more recently argued should be provided through various forms of managed competition based on market incentives the concept of the market mechanism has also been applied widely to ecological matters economists have proposed that if a given reduction in pollution emissions is the goal this reduction is efficiently achieved by allocating rights to pollute and then allowing market trading in these rights dales 1968 pearce et al 1989 a carbon tax is often advocated as an effective way of using market forces to achieve a desired reduction in carbon dioxide emissions for global warming purposes oecd 1992 other economists have argued that conservation of water supplies and thus avoidance of the need to build environmentally harmful dams and other water facilities is efficiently achieved by creating a system of water rights and then allowing market trading in these rights anderson 1983 many other types of environmental objectives could in principle be achieved by setting a target and then using the market mechanism to realize this goal tietenberg 1993 zylicz 1991 economists have typically also argued that the market mechanism like other tools of professional economics is a value neutral device its efficiency and effectiveness rest on technical grounds alone economists assert that are independent of any particular cultural or broader value circumstances however as this paper will argue the economic case for the market mechanism is actually grounded in the existence of a particular set of social values if these values were in fact commonly rejected in society markets would lose the efficiency advantages that mainstream economics claims for them to be sure the values on which market efficiency depends have in fact been broadly accepted in american life that is why the market mechanism has been as widely proposed and in a number of cases sometimes involving the environment used successfully to be specific the particular value system that has supported the functioning of the market mechanism in the united states has been the belief in economic progress the market is an engine of great social dislocation as well as economic advance american society has been willing to tolerate the major dislocations because it has believed that they

business cycles synchronicity and income levels has globalisation brought us closer than ever research on business cycle linkages shows a tendency to model countries of relatively the same income levels jointly however the issue of whether these countries move along the same business cycles has not been formally investigated in the literature in this paper we take this approach and investigate whether each group of countries follows its own dynamics and is therefore subjected to the same business cycle and whether these cycles are independent of each other across income groups results indicate that high income per capita countries hics tend to be guided by stronger similarity in business cycles than countries in the middle mics and low income lics groups in search for an explanation of the business cycles synchronicity observed panel data analysis was explored the results from the robust fixed effects estimation show neither trade openness nor shocks to consumption underlie international business cycle synchronization but rather shocks to oil prices

deposit interest rate ceilings as credit supply shifters bank level evidence on the effects of regulation q abstract how did deposit interest rate ceilings an important feature of the u s regulatory regime until the mid 1980s affect individual banks lending and the transmission of monetary policy to credit i estimate the effect of deposit rate ceilings inscribed in regulation q on commercial banks credit growth using a historical bank level data set starting in 1959 banks credit growth contracted sharply when legally fixed deposit rate ceilings were binding interaction terms with monetary policy suggest that the policy impact on bank level credit growth was non linear and significantly larger when rate ceilings were in place bank size and capitalization mitigate these effects at the bank level short term interest rates exceeding the legally fixed deposit rate ceilings identify policy induced credit supply shifts that disappeared with deposit rate deregulation and thus weakened the bank lending channel substantially since the early 1980s

option pricing with stochastic volatility information time vs calendar time empirical evidence has shown that subordinated processes represent well the price changes of stocks and futures using either transaction counts or trading volume as a proxy for information arrival it supports the contention that volatility is stochastic in calendar time because of random information arrival and thus becomes stationary in information time this contention has also been supported later in theoretical models in this paper we investigate the implication of this contention to option pricing first we price the option in calendar time where the return of the underlying asset follows a jump subordinated process we extend rubinstein s rubinstein m 1976 the valuation of uncertain income streams and the valuation of options bell j econom management sci 7 407 425 and ross s ross s 1989a information and volatility the no arbitrage martingale approach to timing and resolution irrelevancy finance44 1 17 martingale valuation methodology to incorporate the pricing of volatility risk the resulting equilibrium formula requires estimating seven parameters upon implementation we then make a stochastic time change from calendar time to information time in order to obtain a stationary underlying asset return process to price the option we find that the isomorphic option has random maturity because the number of information arrivals prior to the option s calendar time expiration date is random we value the option using dynkin s dynkin e b 1965 markov processes vols i and ii springer verlag berlin and new york version of the feynman kac formula that allows for a random terminal date the resulting information time formula requires estimating only one additional parameter compared to the black scholes s in practical application in this regard the time change has reduced the computational complexity of the option pricing problem simulations show that the formula may outperform the black scholes black f m scholes 1973 the pricing of options and corporate liabilities political econom 81 637 659 and merton merton robert c 1976a option pricing when underlying stock returns are discontinuous financial econom 3 125 143 models in pricing currency options as a first attempt to derive valuation relationships in the information time economy this investigation may suggest that the information time approach is a functional alternative to the current calendar time norm it is especially suitable for deriving volatility free portfolio insurance strategies

the long run determinants of north south terms of trade and some recent empirical evidence abstract this paper reviews some recent evidence of the long run decline in the terms of trade of primary commodities versus manufactures in the context of north south trade this evidence is evaluated in the light of competing explanations of the sources of the observed long run trends in the context of a model of north south trade which includes a general resource labor and capital in the north and specific factors in a dual economy model of the south changes in factor supply sectoral and factoral bias in technical change biased demand conditions changes in the pattern of protection and institutional elements all play a role in determining the evolution of commodity and factor prices the lewis hypothesis of sectoral bias in the pattern of technical change towards temperate agriculture in the north and against tropical agriculture in the south is then reexamined in the light of the recent empirical evidence on terms of trade movements and some sketchy evidence presented on the patterns of bias in technical change in the north and the south the evidence is not consistent with an absolute technical change bias towards temperate agriculture in the north rather the rate of technical change in temperate agriculture is now comparable to that experienced in manufactures so that engel curve effects now assert the major downward pressure on the long run terms of trade between temperate agriculture commodities and manufactures overriding the effects of diminishing returns to natural resources as northern population expands the empirical evidence onbiased technical change in the south is much more sketchy and the evidence on various components of north south terms of trade is more varied

revisiting the revisited terms of trade will china make a difference in challenging the conventional wisdom at the time singer and prebisch posited a number of explanations for declining terms of trade of developing economies including both country and product specific factors over the past decade we have begun to witness a simultaneous process of price differentiation within commodities with the prices of some commodities increasing and within manufacturing with the price of many manufactures falling these price changes may reverse the decline in the terms of trade of commodity producers the entry of china into the global market has played an important role in this augmenting the demand for many hard commodities its role as an exporter of manufactures coupled with concentration in global buying may undermine the prices of many manufactures

the time varying volatility of macroeconomic fluctuations we investigate the sources of the important shifts in the volatility of us mac roeconomic variables in the postwar period to this end we propose the esti mation of dsge models allowing for time variation in the volatility of the structural innovations we apply our estimation strategy to a large scale model of the business cycle and find that shocks specific to the equilibrium condition of investment account for most of the sharp decline in volatility of the last two decades jel c51 e32

revealing the preferences of the us federal reserve we use bayesian methods to estimate changes in us post war monetary policy in the smets and wouters model we perform the estimations by allowing for a break in monetary policy at the time of volcker s appointment as chairman this enables us to capture changes in the monetary policy regime introduced by volcker during the volcker greenspan period we find support for the assumption that monetary policy in the volcker greenspan period performed optimally under commitment our estimation strategy allows us to estimate the preferences of the us federal reserve in the volcker greenspan period where the main objective of policy appears to be inflation followed by interest rate stabilization output growth and interest rate smoothing we find that the great moderation of output growth is explained by a combination of two factors the decrease in the volatility of the structural shocks and the improved monetary policy conduct inflation stabilization however is mainly due to the change in monetary policy that took place at the beginning of volcker s mandate copyright 2010 john wiley sons ltd

on jump processes in the foreign exchange and stock markets exchange rates exhibit systematic discontinuities even after allowingfor conditional heteroskedasticity in the diffusion process the results are much more significant in theforeign exchange market than in the stock market which suggests differences in the structure of these markets finally this jump component is shown to explain some of the empirically observed mispricings in the currency options market the objective of this article is to analyze and compare the empirical distribution of returns in the stock market and in the foreign exchange market there are a number of reasons why a better understanding of the stochastic processes driving prices in these markets would be useful many financial models rely heavily on the assumption of a particular stochastic process while relatively little attention is paid to the empirical fit of the postulated distribution as a result models like option pricing models are applied indiscriminately to various markets such as the stock market and the foreign exchange market when the underlying processes may be fundamentally different the foreign exchange market for instance is characterized by active exchange rate man

the heterogeneous great moderation in this paper i show that a more accurate analysis of the great moderation leads to interesting and novel findings about macroeconomic volatility dynamics in the last decades the main empirical result of the paper is that the great moderation has diversely affected macroeconomic volatility at different horizons short run business cycle and medium run i refer to this phenomenon as the heterogeneous great moderation across frequencies i formally test these findings by defining a frequency domain structural break test that detects the presence of a break in the variance of real macroeconomic variables at different frequencies i derive its asymptotic and small sample properties and i apply it to u s macroeconomic variables to provide statistical evidence that the great moderation is mainly confined to short run fluctuations i finally use a dsge model to investigate which elements of the model can generate the heterogeneous great moderation i find that whereas just a decline of the magnitude of the shocks and a change in the monetary policy cannot replicate the stylized facts accounting for the increased persistence of the exogenous disturbances is the key feature for generating the heterogeneous great moderation

the relation between price changes and trading volume a survey this paper reviews previous and current research on the relation between price changes and trading volume in financial markets and makes four contributions first two empiri cal relations are established volume is positively related to the magnitude of the price change and in equity markets to the price change per se second previous theoretical research on the price volume relation is summarized and critiqued and major insights are emphasized third a simple model ofthe price volume relation is proposed that is consis tent with several seemingly unrelated or contradictory observations and fourth several directions for future research are identified

has monetary policy become more effective we investigate the implications of changes in the structure of the u s economy for monetary policy effectiveness estimating a vector autoregression over the pre and post 1980 periods we provide evidence of a reduced effect of monetary policy shocks in the latter period we estimate a structural model that replicates well the economy s response in both periods and perform counterfactual experiments to determine the source of the change in the monetary transmission mechanism and in the economy s volatility we find that by responding more strongly to inflation expectations monetary policy has stabilized the economy more effectively in the post 1980 period

eminent economists their life philosophies introduction the passion for research mauric allais i know a hawk from a handsaw kenneth j arrow on my attitudes sociopolitical and methodological william j baumol recollections and reflections of a comparativist abram bergson from chemistry to economics and beyond kenneth e boulding my quest for economic knowledge karl brunner from the inside looking out james m buchanan random walk and life philosophy gerard debreu how i tried to become an economist evsey d domar nicholas georgescu roegen about himself nicholas georgescu roegen autobiographical notes with reflections frank hahn my working philosophy charles p kindleberger my professional life philosophy l r klein social science ethics and the role of the public sector richard a musgrave my apprenticeship as an economist austin robinson reflections on political economy past present and future w w rostow my life philosophy policy credos and working ways paul a samuelson my search for welfare tibor scitovsky living in interdisciplinary space herbert a simon notes on copying robert m solow solving the most urgent problems first jan tinbergen scientific humanism as an ideal shigeto tsuru index

monopoly power and uneven development baran revisited baran examined the implications of the rise in monopoly power in advanced economies for the underdevelopment in poor countries and the process of uneven development on a world scale this article examines his work critically and then presents a north south model which defines uneven development in a precise manner and analyses the mechanism by which the rise in monopoly power leads to such uneven development it is shown that the process can work even without reference to imperialism which is a central but controversial element in baran s analysis

tests of an american option pricing model on the foreign currency options market this paper tests the ability of the american option pricing model proposed by parkinson 18 or mason 14 to explain the pricing of the foreign currency options traded on the philadelphia stock exchange from february 28 1983 to march 26 1985 we find that the model underprices out of the money options relative to at the money and in the money options this relative underpricing is driven by an underpricing of out of the money call options of short maturity in addition the degree of relative mispricing for most categories of options is shown to be a decreasing function of the time to maturity of the options longer maturity options appear to trade at similar levels of implied volatility whether they are in at or out of the money most of these biases appear consistent with the fact that the underlying spot currency rate follows a mixed jump diffusion process as described in 17

the structural dynamics of output growth and inflation some international evidence we examine the dynamics of output growth and inflation in the us euro area and uk using a structural time varying coefficient var there are important similarities in structural inflation dynamics across countries output growth dynamics differ swings in the magnitude of inflation and output growth volatilities and persistences are accounted for by a combination of three structural shocks changes over time in the structure of the economy are limited and permanent variations largely absent changes in the volatilities of structural shocks matter

quadratic variation based dynamic strategies the paper analyzes a family of dynamic trading strategies which do not rely on any stochastic process assumptions aside from continuity and positivity and in particular do not require predicting future volatilities derivative payoffs can still be replicated except that this occurs at the stopping time at which the realized cumulative squared volatility hits a predetermined level the application of these results to portfolio insurance is emphasized and hedging strategies studied by black and jones and by brennan and schwartz are generalized classical results on european style options arise as special cases for example the initial cost of replicating a call or a put under the new method is given by a generalized black scholes formula which yields the ordinary black scholes formula when the volatility is derterministic

option values under stochastic volatility theory and empirical estimates abstract this paper numerically solves the call option valuation problem given a fairly general continuous stochastic process for return volatility statistical estimators for volatility process parameters are derived and parameter estimates are calculated for several individual stocks and indices the resulting estimated option values do not differ dramatically from black scholes values in most cases although there is some evidence that for longer maturity index options black scholes overvalues out of the money calls in relation to in the money calls

monetary policy shocks and foreign investment income evidence from a large bayesian var abstract this paper assesses the transmission of monetary policy in a large bayesian vector autoregression based on the approach proposed by banbura et al 2010 the paper analyzes the impact of monetary policy shocks in the united states and canada not only on a range of domestic aggregates trade flows and exchange rates but also foreign investment income the analysis provides three main results first a surprise monetary policy contraction has a statistically important impact on both gross and net foreign investment income flows in both countries against the background of growing foreign wealth and investment income this result provides preliminary evidence that foreign balance sheet channels might play an increasingly significant role for monetary transmission second the impact of monetary policy on foreign investment income flows differs considerably across asset categories and over time suggesting that the investment instruments and the currency denomination of a country s foreign assets and liabilities are potentially relevant for the way in which monetary policy affects the domestic economy finally the results support existing evidence on the effectiveness of large vector autoregressions and the bayesian shrinkage approach in eliminating price and exchange rate puzzles

spillovers to low income countries importance of systemic emerging markets this article documents the expanding economic linkages between low income countries lics and a narrow group of emerging market em leaders that have become major players in international trade and financial flows var models show that these linkages have increased the share of growth volatility that can be attributed to foreign shocks in lics dynamic panel models further analyse the impact of lic trade orientation and production structure on the sensitivity to foreign shocks the empirical results demonstrate that the elasticity of growth to trading partners growth is high for lics in three out of the five regions asia latin america and the caribbean and europe and central asia however for commodity exporting lics in sub saharan africa and the middle east terms of trade shocks and demand from the em leaders are the main channels of transmission of foreign shocks

optimal control of heteroscedastic macroeconomic models summary this paper analyses the implications of heteroscedasticity for optimal macroeconomic policy and welfare we find that changes in the variance structure driven by exogenous processes like generalized autoregressive conditional heteroscedasticity garch affect welfare but not the optimal feedback rule however changes in the variance structure driven by state dependent processes affect both we also derive certainty equivalent transformations of state dependent volatility models that allow standard quadratic dynamic programming algorithms to be employed to study optimal policy these results are illustrated numerically using a reduced form model of the us economy in which changes in volatility are driven by a garch process and the rate of inflation copyright 2015 john wiley sons ltd

the u s business cycle 1867 2006 a dynamic factor approach we estimate a stock watson index of economic activity to assess u s business cycle volatility since 1867 we replicate the great moderation of the 1980s and 1990s and find exceptionally low volatility also in the golden age of the 1960s postwar moderation relative to pre 1914 occurs under constant but not time varying factor loadings suggesting structural change toward more volatile sectors for comparable series the u s postwar business cycle was as volatile overall as under the classical gold standard but much less so during the great moderation and the golden age

on valuing american call options with the black scholes european formula empirical papers on option pricing have uncovered systematic differences between market prices and values produced by the black scholes european formula such biases have been found related to the exercise price the time to maturity and the variance we argue here that the american option variant of the black scholes formula has the potential to explain the first two biases and may partly explain the third it can also be used to understand the empirical finding that the striking price bias reverses itself in different sample periods the expected form of the striking price bias is explained in detail and is shown to be closely related to past empirical findings the black scholes european option pricing model tends to exhibit systematic empirical biases when used to value american call options the reported biases

were there regime switches in u s monetary policy working paper 2004 14 june 2004 abstract a multivariate model identifying monetary policy and allowing for simultaneity and regime switching in coefficients and variances is confronted with u s data since 1959 the best fit is with a model that allows time variation in structural disturbance variances only among models that also allow for changes in equation coefficients the best fit is for a model that allows coefficients to change only in the monetary policy rule that model allows switching among three main regimes and one rarely and briefly occurring regime the three main regimes correspond roughly to periods when most observers believe that monetary policy actually differed and the differences in policy behavior are substantively interesting though statistically ill determined the estimates imply monetary targeting was central in the early 80s but was also important sporadically in the 70s the changes in regime were essential neither to the rise in inflation in the 70s nor to its decline in the 80s jel classification e52 e47 c53 key words counterfactuals lucas critique policy rule monetary targeting simultaneity volatility model comparison i the debate over monetary policy change in an influential paper clarida gali and gertler 2000 cgg presented evidence that us monetary policy changed between the 1970 s and the 1980 s indeed that in the 70 s it was drastically worse they found that the policy rule apparently followed in the 70 s was one that when embedded in most stochastic general equilibrium models would imply non uniqueness of the equilibrium and hence vulnerability of the economy to sunspot fluctuations of arbitrarily large size their estimated policy rule for the later period on the other hand eliminated this indeterminacy these results are a possible explanation of the volatile and rising inflation of the 70 s and of its subsequent decline the cgg analysis has two important weaknesses one is that it fails to account for stochastic volatility us macroeconomic variables and particularly the federal funds rate have gone through periods of tranquility and of agitation with forecast error variances varying greatly from period to period ignoring such variation does not lead to inconsistent estimates of model parameters when the forecasting equations themselves are constant but it strongly biases toward a finding of changed parameters tests of the stability of the forecasting equations the other weakness is that the cgg analysis rests on powerful and implausible identifying assumptions they require that we accept that the response of the monetary authority to expected future inflation and output does not depend on the recent history of inflation money growth or output it is hard to understand why this should be so especially in the 70 s when monetarism was a prominent theme in policy debates congress was requiring reports from the fed of projected time paths of monetary aggregates and financial markets were reacting sensitively to weekly money supply numbers the requirement for existence and uniqueness of equilibrium in dynamic models is that the monetary policy rule show a more than unit response of interest rates to the sum of the logs of all nominal variables that appear on the right hand side of the reaction function if we force a particular measure of expected future inflation to proxy for all the nominal variables that actually appear independently in the reaction function we are bound to get distorted conclusions on the one hand because expected future inflation will be a noisy measure of the full set of nominal influences on policy we might get downward bias in our estimates from the usual errorsin variables effect on the other hand to the extent that expected future inflation like most expected future values shows less variation than current nominal variables we could find a mistaken scaling up of coefficients

constraints on dematerialisation and allocation of natural capital along a sustainable growth path abstract to study societal and biophysical constraints on sustainability we present an extension of the neoclassical growth model with two new concepts allocation of natural capital and dematerialisation we consider that anthropogenic environmental impact is correlated with the material throughput of the economy materialisation and that due to composition change and innovation this throughput can be reduced the process of dematerialisation we also consider that the allocation of natural capital to production negatively affects the endogenous dynamics of ecosystems reducing the total amount of environmental services ecosystems provide according to our model it is possible to achieve unbounded economic growth by keeping the natural system in steady state balanced growth however is only possible for special parameter values

an extension of the black scholes model of security valuation abstract this paper provides a formula for the market value of a security whose dividends and liquidation value depend on securities with diffusion dividend and price processes the solution is in terms of the feynman kac formula solving the partial differential equation determining the derivative sucurity s unique arbitrage free value the interest rate process may be stochastic markets need not be dynamically complete

a dynamic equilibrium model of asset prices and transaction volume a dynamic general equilibrium model of capital asset pricing is constructed in which the volume of capital traded is determined endogenously the model also gives rise to a novel asset pricing formula it is shown that temporary shocks can give rise to serially correlated changes in the price of capital and transaction volume that persist long after the initial disturbance the frequency and amplitude of the resulting cycles are related to the length of the agent s planning horizon and the discount factor the model s implications for explaining asset price volatility are also explored

general equilibrium pricing of options on the market portfolio with discontinuous returns when the price process for a long lived asset is of a mixed jump diffusion type pricing of options on that asset by arbitrage is not possible if trading is allowed only in the underlaying asset and a risk less bond using a general equilibrium framework we derive and analyze option prices when the underlying asset is the market portfolio with discontinuous returns the premium for the risk of jumps and the diffusion risks forms a significant part of the prices of the options in this economy an attempted replication of call and put options by the black scholes type of trading strategies may require substantial infusion of funds when jumps occur we study the cost and risk implications of such dynamic hedging plans article published by oxford university press on behalf of the society for financial studies in its journal the review of financial studies

structural changes in the us economy is there a role for monetary policy this paper investigates the contribution of monetary policy to the changes in output growth and inflation dynamics in the us we identify a policy shock and a policy rule in at ime varying coefficients var using robust sign restrictions the transmission of policy shocks has been relatively stable the variance of the policy shock has decreased over time but policy shocks account for a small fraction of the level and of the variations in inflation and output growth volatility and persistence we find little evidence of a significant increase in the long run response of the interest rate to inflation a more aggressive inflation policy in the 1970s would have produced large output growth costs

the price variability volume relationship on speculative markets this paper concerns the relationship between the variability of the daily price change and the daily volume of trading on the speculative markets our work extends the theory of speculative markets in two ways first we derive from economic theory the joint probability distribution of the price change and the trading volume over any interval of time within the trading day and second we determine how this joint distribution changes as more traders enter or exit from the market the model s parameters are estimated by fiml using daily data from the 90 day t bills futures market the results of the estimation can reconcile a conflict between the price variability volume relationship for this market and the relationship obtained by previous investigators for other speculative markets this paper concerns the relationship between the variability of the daily price change and the volume of trading on speculative markets previous empirical studies 2 3 6 12 14 16 of both futures and equity markets always find a positive association between price variability as measured by the squared price change ap2 and the trading volume 2 there are two explanations for the relationship clark s 2 explanation which is secondary to his effort to explain why the probability distribution of the daily price change is leptokurtic emphasizes randomness in the number of within day transactions in clark s model the daily price change is the sum of a random number of within day price changes the variance of the daily price change is thus a random variable with a mean proportional to the mean number of daily transactions clark argues that the trading volume is related positively to the number of within day transactions and so the trading volume is related positively to the variability of the price change the second explanation is due to epps and epps 6 their model examines the mechanics of within day trading the change in the market price on each within day transaction or market clearing is the average of the changes in all of the traders reservation prices epps and epps assume there is a positive relationship between the extent to which traders disagree when they revise their reservation prices and the absolute value of the change in the market price that is an increase in the extent to which traders disagree is associated with a larger absolute price change the price variability volume relationship arises then because the volume of trading is positively related to the extent to which traders disagree when they revise their reservation prices

nonparametric tests of alternative option pricing models using all reported trades and quotes on the 30 most active cboe option classes from august 23 1976 through august 31 1978

valuation of american call options on dividend paying stocks empirical tests abstract this paper examines the pricing performance of the valuation equation for american call options on stocks with known dividends and compares it with two suggested approximation methods the approximation obtained by substituting the stock price net of the present value of the escrowed dividends into the black scholes model is shown to induce spurious correlation between prediction error and 1 the standard deviation of stock return 2 the degree to which the option is in the money or out of the money 3 the probability of early exercise 4 the time to expiration of the option and 5 the dividend yield of the stock a new method of examining option market efficiency is developed and tested