frontiers of real time data analysis in the past ten years researchers have explored the impact of data revisions in many different contexts researchers have examined the properties of data revisions how structural modeling is affected by data revisions how data revisions affect forecasting the impact of data revisions on monetary policy analysis and the use of real time data in current analysis this paper summarizes many of the questions for which real time data analysis has provided answers in addition researchers and institutions have developed better real time data sets around the world still additional research is needed in key areas and research to date has uncovered even more fruitful areas worth exploring jel c52 c53 c80 e01

evaluating greening farm policies a structural model for assessing agri environmental subsidies this study uses a structural econometric model to evaluate the impacts of support from a european union agri environmental program designed to reduce nutrient pollution from agricultural land drawing on a representative sample of individual grain farms we first quantify the effects of agri environmental payments on farms decisions on land allocation and on fertilizer use we then combine the predicted land allocation and fertilizer use with environmental production functions to quantify the impact on nutrient loading finally we assess the monetary value of reduced nutrient pollution drawing on a recent valuation study

nonpecuniary benefits to farming implications for supply response to decoupled payments we develop a household model wherein farmers allocate labor to maximize utility from leisure consumption and nonpecuniary benefits from farming the model shows that farmers with decreasing marginal utility of income respond to higher decoupled payments by decreasing off farm labor and increasing farm labor resulting in greater agricultural output we then estimate the difference between farm and off farm returns to labor using data from three nationally representative farm household surveys the finding of a large on farm off farm wage differential provides compelling evidence of substantial nonpecuniary benefits from farming

farm growth and survival econometric evidence for individual farms in upper austria this article investigates survival and growth of more than 50 000 upper austrian farm households within a maximum likelihood sample selection framework the results suggest that age schooling and sex of the farm operator size of the farm family and off farm employment status as well as initial farm size significantly influence farm growth and survival the present study provides support for the notion of a disappearing middle in the size distribution the process of polarization is closely related to the off farm employment status of farms correcting for sample attrition bias is important when analyzing the performance of part time farms

var estimation and forecasting when data are subject to revision we show that howrey s method for producing economic forecasts when data are subject to revision is easily generalized to handle the case where data are produced by a sophisticated statistical agency the proposed approach assumes that government estimates are efficient with a finite lag it takes no stand on whether earlier revisions are the result of news or of reductions in noise we present asymptotic performance results in the scalar case and illustrate the technique using several simple models of economic activity in each case it outperforms both conventional var analysis and the original howrey method it produces gdp forecasts that are competitive with those of professional forecasters special cases and extensions of the analysis are discussed in a series of appendices that are available online

acreage decisions under risk the case of corn and soybeans an acreage supply response model is developed under expected utility maximization the resulting framework is used to specify and estimate a system of risk responsive acreage equations for corn and soybeans in the united states particular attention is given to the truncation effects of government price supports on the distribution of corn and soybean prices also a wealth variable is included in the acreage equations the empirical results indicate that risk and wealth variables play an important role in cornsoybean acreage decisions the analysis also shows that cross commodity risk reduction is important in acreage allocation decisions

improving real time estimates of output and inflation gaps with multiple vintage models real time estimates of output gaps and inflation gaps differ from the values that are obtained using data available long after the event part of the problem is that the data on which the real time estimates are based is subsequently revised we show that vector autoregressive models of data vintages provide forecasts of post revision values of future observations and of already released observations capable of improving estimates of output and inflation gaps in real time our findings indicate that annual revisions to output and inflation data are in part predictable based on their past vintages this article has online supplementary materials

united states farm commodity programs and land use we estimate the impact of government payments on united states land use using county level data from the national resources inventory and the census of agriculture in 1987 1992 and 1997 although payments were made under decoupled support programs effects on land use are found to be significant on average for the years studied our simulations indicate that united states cropland acreage would have been 89 million acres 22 less if program payments had been reduced to half their observed level holding market prices of commodities constant percentage reductions are largest in marginal crop producing areas of the nation

on nonparametric supply response analysis in this paper we explore the usefulness of nonparametric methods in the investigation of production behavior and the estimation of price elasticities of output supply and input demand functions the approach can handle the situation where some data points are not consistent with production theory the method is illustrated by estimating supply demand elasticities of outputs and inputs in u s agriculture

asymmetry and nonstationarity in the farm size distribution of wisconsin milk producers an aggregate analysis a markov model is developed to test the nonstationarity and asymmetry of factors affecting the evolution of wisconsin dairy farms using aggregate data the model is used to examine how prices interest rates debt drought and the dairy termination program affected farm growth and the entry and exit of wisconsin dairy farms by size categories during 1972 92

credit indicators as predictors of economic activity a real time var analysis using readily available indicators of the profitability price and availability of credit the term spread junk bond spread and banks willingness to lend as reported by the federal reserve we show that it is possible to significantly improve on the real time output and employment predictions of forecasting professionals at the medium run horizons that are most relevant to policymakers and private decision makers key to this improvement is a flexible state space model of data revisions the willingness to lend variable is the best real time predictor of gdp growth for forecasting job growth all three credit indicators prove helpful

modeling supply response in a multiproduct framework the paper models multiproduct supply response in agriculture and tests key assumptions traditionally maintained in supply response studies the technology is approximated by a restricted profit function the properties of the restricted profit function are imposed during estimation the hypothesis that maintains the existence of output price and quantity indexes that satisfy the adding up property is rejected the existence of individual production functions for each output is also rejected unless joint production is permitted the estimates of responsiveness of a particular commodity to changes in own price or prices of competing outputs are likely to be considerably understated

the dynamic effects of aggregate demand and supply disturbances we interpret fluctuations in gnp and unemployment as due to two types of disturbances disturbances that have a permanent effect on output and disturbances that do not we interpret the first as supply disturbances the second as demand disturbances demand disturbances have a hump shaped mirror image effect on output and unemployment the effect of supply disturbances on output increases steadily over time peaking after two years and reaching a plateau after five years

data revisions are not well behaved we document the empirical properties of revisions to major macroeconomic variables in the united states our findings suggest that they do not satisfy simple desirable statistical properties in particular we find that these revisions do not have a zero mean which indicates that the initial announcements by statistical agencies are biased we also find that the revisions are quite large compared to the original variables and they are predictable using the information set at the time of the initial announcement which means that the initial announcements of statistical agencies are not rational forecasts

an intertemporal general equilibrium model of asset prices this paper develops a continuous time general equilibrium model of a simple but complete economy and uses it to examine the behavior of asset prices in this model asset prices and their stochastic properties are determined endogenously one principal result is a partial differential equation which asset prices must satisfy the solution of this equation gives the equilibrium price of any asset in terms of the underlying real variables in the economy in this paper we develop a general equilibrium asset pricing model for use in applied research an important feature of the model is its integration of real and financial markets among other things the model endogenously determines the stochastic process followed by the equilibrium price of any financial asset and shows how this process depends on the underlying real variables the model is fully consistent with rational expectations and maximizing behavior on the part of all agents our framework is general enough to include many of the fundamental forces affecting asset markets yet it is tractable enough to be specialized easily to produce specific testable results furthermore the model can be extended in a number of straightforward ways consequently it is well suited to a wide variety of applications for example in a companion paper cox ingersoll and ross 7 we use the model to develop a theory of the term structure of interest rates many studies have been concerned with various aspects of asset pricing under uncertainty the most relevant to our work are the important papers on intertemporal asset pricing by merton 19 and lucas 16 working in a continuous time framework merton derives a relationship among the equilibrium expected rates of return on assets he shows that when investment opportunities are changing randomly over time this relationship will include effects which have no analogue in a static one period model lucas considers an economy with homogeneous individuals and a single consumption good which is produced by a number of processes the random output of these processes is exogenously determined and perishable assets are defined as claims to all or a part of the output of a process and the equilibrium determines the asset prices our theory draws on some elements of both of these papers like merton we formulate our model in continuous time and make full use of the analytical tractability that this affords the economic structure of our model is somewhat similar to that of lucas however we include both endogenous production and

an international study of tax effects on government bonds it is shown that coupon bonds alone are not sufficient to span time dated claims on ordinary income capital gains and non taxable wealth in an incomplete bond market where the pure dated claims are not spanned by existing bonds marginal rates of substitution between present consumption and pure dated claims on ordinary income capital gains income and non taxable wealth respectively can differ across bondholders however the relative pricing of coupon bonds in each of these countries is shown to be consistent with the tax status of the major non tax exempt holders of government debt

agricultural price transmission elasticity importance of controlling for unobserved common factors a voluminous amount of the literature estimates price transmission from world markets to domestic markets ignoring unobserved factors that commonly affect domestic markets this article reevaluates the long run and short run transmission elasticity of world food price shocks to domestic markets using a common factor framework that takes unobserved common factors that are correlated with regressors into consideration in the estimation annual price data for rice wheat and maize for a panel of developed and developing countries that are observed over the period of 1960 2007 are used the results from a common factor framework to those that do not account for common factors are then compared our findings suggest that ignorance of common factors is likely to result in upwardly biased elasticity estimates

a simple approach to interest rate option pricing a simple introduction to contingent claim valuation of risky assets in a discrete time stochastic interest rate economy is provided taking the term structure of interest rates as exogenous closed form solutions are derived for european options written on 1 treasury bills 2 interest rate forward contracts 3 interest rate futures contracts 4 treasury bonds 5 interest rate caps 6 stock options 7 equity forward contracts 8 equity futures contracts 9 eurodollar liabilities and 10 foreign exchange contracts article published by oxford university press on behalf of the society for financial studies in its journal the review of financial studies

output and unemployment dynamics in the united states 1950 1985 for us data over 1950 1985 the stochastic components of gnp growth and the unemployment rate appear to be stationary and there is substantial feedback between these variables the unconditional mean rate of unemployment in a joint model thus provides a natural benchmark in discussions of the business cycle a bivariate var model is used to describe output unemployment dynamics to estimate the degree of persistence of output innovations and to decompose output into trend and cycle the bivariate results are interpreted using a restricted var and it is shown that a closely related cyclical measure can be obtained directly from the okun s law equation

the impact of diesel price on upstream and downstream food prices evidence from sao paulo abstract the literature on the transmission of oil price shocks to prices along the food supply chain has widely ignored how shocks upstream differ from downstream ones this article examines this issue by modelling upstream and downstream diesel price shocks along the nutritional high value food supply chain in sao paulo using a vector error correction approach and monthly data from july 2001 to december 2013 we estimate short run and long run dynamics in producer and retail prices of meat eggs dairy and fats oil due to changes in the average monthly price of diesel the results of the granger causality analysis show that the price of diesel cannot be used to predict the behaviour of producer prices in all the markets under study and the price of diesel predicts retail price only in the egg market this result is in line with the nature of price controls in brazil as of january 2002 the prices charged by distributors and retailers have been liberalized although wholesale prices of the derivatives including that of diesel continue to be set by the state oil company with the objective of controlling inflationary pressures the results of the response of food prices to diesel price shocks show a positive response of both upstream and downstream prices of egg and dairy products both upstream and downstream while the opposite direction occurs in the fat and meat markets albeit the initial positive shock of the producer price of meat the findings of the study show the important role of public policy in determining the nature of price transmission along the food supply chain

the valuation of multivariate contingent claims in discrete time models there are several examples in the literature of contingent claims whose payoffs depend on the outcomes of two or more stochastic variables familiar cases of such claims include options on a portfolio of options options whose exercise price is stochastic and options to exchange one asset for another this paper derives risk neutral valuation relationships rnvrs in a discrete time setting that facilitate the pricing of such complex contingent claims in two specific cases joint lognormally distributed underlying variables and constant proportional risk aversion on the part of investors and joint normally distributed underlying variables and constant absolute risk aversion preferences respectively this methodology is then applied to the valuation of several interesting complex contingent claims such as multiperiod bonds multicurrency option bonds and investment options

term structure movements and pricing interest rate contingent claims this paper derives an arbitrage free interest rate movements model ar model this model takes the complete term structure as given and derives the subsequent stochastic movement of the term structure such that the movement is arbitrage free we then show that the ar model can be used to price interest rate contingent claims relative to the observed complete term structure of interest rates this paper also studies the behavior and the economics of the model our approach can be used to price a broad range of interest rate contingent claims including bond options and callable bonds

nonparametric analysis of technical and allocative efficiencies in production in this paper we extend varian s 1984 nonparametric production analysis to situations when the set of observed output input and price data is not consistent with profit maximization for at least one firm in such cases varian s results imply that no production possibility set containing all observations can rationalize the observed data we identify each firm whose performance given the prices faced by it may be found consistent with profit maximization relative to some production possibility set containing all observed output input vectors we show that the set 4 of all such firms can itself be weaklv rationalized in the sense that there exists a closed convex and monotone production possibility set that contains all the observations and relative to which the performance of all the firms in the set 8o is consistent with profit maximization given their respective prices by definition firms not included in this largest set d of efficient observations unambiguously deviate from profit maximizing behavior for any production possibility set containing all observations we follow farrell 1957 and analyze these deviations into technical and allocative efficiency measures considering as admissible all closed convex and monotone production possibility sets relative to which the performance of each firm in the set g remains consistent with profit maximization we then describe nonparametric methods for determining the tightest upper and lower bounds on the technical allocative and aggregate efficiency measures evaluated relative to all such admissible production possibility sets it is seen that the tightest upper bound on the technical efficiency measure is the same as the value computed by the nonparametric efficiency evaluation technique known as data envelopment analysis thus establishing a link between this literature in management science operations research and the nonparametric production analysis in economics

farm level production effects from participation in government commodity programs did the 1996 federal agricultural improvement and reform act make a difference in theory lump sum transfers are a way to redistribute wealth without distorting production decisions recent agricultural policy reforms are an unusual large scale application of this concept the 1996 federal agricultural improvement and reform fair act removed most price contingent agricultural subsidies and replaced them with production flexibility contracts lump sum payments with few ties to farmers production decisions the payments were envisioned as way to maintain income transfers to agricultural interests while minimizing production distortions the united states has argued that these decoupled agricultural payments are minimally trade distorting usda ers there is a great deal of uncertainty about how the system of agricultural payments established under the 1996 reforms affects production some including representatives from developing nations with domestic agricultural sectors that compete with the united states contend that decoupled payments significantly affect agricultural production and trade two general arguments underpin this assertion first decoupled payments are not really lump sum that is despite the reforms important links to production remain for example there are restrictions in the fair act that preclude new vegetable plantings or the conversion of land to nonagricultural uses second the perfect market assumptions underpinning the

family farm dynamics in canada and israel the case of farm exits abstract canada is one of the few countries for which data exist on individual family farms over time using these data researchers have been able to show that much of the microdynamics of family farms in canada e g changes in size distribution can be attributed to farmer entry and exit however the behavioral aspects of the exit decision received little attention in the literature a comparison of canadian and israeli data could help us understand these behavioral aspects because of the vast institutional differences between the farm sectors in the two countries and the possible effect of the institutional setup on exit decisions comparison of exit patterns may enable us to identify the dependence of farmers mobility on the institutional setup this may also have policy relevance in both canada and israel exit probability decreases with the extent of off farm work we conclude that off farm work is complementary rather than a substitute for farm work perhaps due to its less volatile nature both canadian and israeli farmers over a certain age are more likely to exit as they become older which is a natural result but exit probability in canada rises much faster with age than in israel the major difference between canadian and israeli farm exit patterns lies in the farm size farm size decreases exit probability in canada but increases it in israel perhaps this is because israeli farm exits are less planned in advance than canadian exits institutional constraints on land transactions in israel may also play a role

the effects of farm subsidies on farm exports in the united states we estimate the elasticity of u s farm exports to u s farm subsidies using a gravity model of state level farm exports to 100 major trading destinations for the period 1999 to 2011 our identification strategy exploits the within state variation that is free of endogeneity bias in the levels and trends of farm subsidies and farm exports we find that a 1 decrease in farm subsidies would reduce u s farm exports by 0 40 per annum this equivalently means that the complete abolishment of the farm subsidy program would reduce u s farm exports by approximately 15 3 billion per year importantly we document robust evidence that amber box subsidy programs such as counter cyclical payments and marketing loan gains have the strongest effect on farm exports while green box subsidy payments such as direct payments have negligible effects finally subsidy payments affect exports only in agricultural commodities not in livestock our subsidy elasticity estimates are statistically significant stable and economically meaningful and are vitally needed by u s and global policymakers in the face of critical domestic and international developments

co movements in commodity prices a note based on network analysis this article analyses co movements in a wide group of commodity prices during the time period 1992 2010 our methodological approach is based on the correlation matrix and the networks inside through this approach we are able to summarize global interaction and interdependence capturing the existing heterogeneity in the degrees of synchronization between commodity prices our results produce two main findings a we do not observe a persistent increase in the degree of co movement of the commodity prices in our time sample however from mid 2008 to the end of 2009 co movements almost doubled when compared with the average correlation b we observe three groups of commodities which have exhibited similar price dynamics metals oil and grains and oilseeds and which have increased their degree of co movement during the sampled period

agricultural price transmission across space and commodities during price bubbles this article investigates agricultural price transmission during price bubbles the empirical approach concerns the horizontal transmission of cereal prices both across different market places and across different commodities the trade policy intervention put forward to mitigate the impact of price exuberance is considered the analysis is performed using italian and international weekly spot cash price data over years 2006 2010 a period of generalized turbulence of agricultural markets firstly the properties of price time series are explored then interdependence across prices is specified and estimated by adopting appropriate cointegration techniques results suggest that the bubble had only a slight impact on the price spread and the temporary trade policy measure when effective has limited this impact

pigs in space modeling the spatial structure of hog production in traditional and nontraditional production regions we posit a spatially explicit county level model of the hog production sector and estimate how numerous firm specific locality specific and spatial agglomeration factors affect the location movement and intensity of hog production within 15 key hog production states spatial agglomeration urban encroachment input availability firm productivity local economy slaughter access and regulatory stringency variables affect the sample regions spatial organization analyses suggest that western states in the sample may shape hog production levels by wielding traditional business recruitment and retention tools e g tax rates environmental stringency while corn belt states may shape hog production via nontraditional tools e g land use controls few sectors have undergone more rapid change in scale structure and organization than the u s swine sector in the past two decades movement to large scale specialized production units reflects past trends in western cattle feeding and dairy enterprises while increasing vertical coordination resembles patterns adopted in the poultry sector several decades ago accompanying these changes in production has been a simultaneous change in the spatial organization of u s hog production industry analysts have forwarded several stylized facts of this spatial reorganization traditional corn belt states have lost in terms of national share of hog production to southeastern great plains and mountain states during the 1980s and 1990s drabenstott hurt as the firms offering swine production and marketing contracts attempt to locate large scale facilities where there are few people cheap land

are statistical reporting agencies getting it right data rationality and business cycle asymmetry this article provides new evidence on the rationality of early releases of industrial production ip and producer price index ppi data rather than following the usual practice of examining only first available and fully revised data we examine the entire revision history for each variable thus we are able to assess for example whether earlier releases of data are in any sense less rational than later releases and when data become rational our findings suggest that seasonally unadjusted ip and ppi become rational after approximately 3 4 months whereas seasonally adjusted versions of these series remain irrational for at least 6 12 months after initial release for all variables examined we find evidence that the remaining revision is predictable from its own past or from publicly available information in other economic and financial variables in addition we find a clear increase in the volatility of revisions during recessions suggesting that early data releases are less reliable in toughe

the swiss payment for milk processed into cheese ex post and ex ante analysis we make use of both an ex post and an ex ante evaluation to analyze the swiss payment for milk processed into cheese this payment for each kilogram of raw milk processed into cheese is issued to milk producers through dairy processors in the ex post evaluation by applying a vector autoregressive model we estimate the effects of reductions of the payment for prices of raw milk used to produce emmentaler gruyere and industrial cheese past declines in the payment have only been partially transmitted to raw milk prices the rate of transmission is higher for milk used for the production of industrial cheese than for artisan cheeses in the ex ante impact evaluation we use a partial equilibrium model and develop a counterfactual scenario in which the payment is removed the payment for milk processed into cheese is found to have effects on cheese production and exports but also has important indirect effects on other dairy products our findings suggest that about two thirds of the payment are benefiting milk producers at the same time the overall welfare losses resulting from the elimination of the aid are smaller than the budget allocated to this measure suggesting a net welfare gain from elimination

the production effects of agricultural income support policies under uncertainty this analysis decomposes the production impacts of income support programs into wealth insurance and coupling effects under the usual assumptions about preferences the wealth and insurance effects of many support programs increase optimal input levels even for supposedly decoupled programs if the program is coupled in the usual sense then all three effects often act in the same direction it is concluded that studies of trade and domestic policy reform in stochastic environments should consider insurance and wealth effects the derivative conditions required to obtain results are also subjected to scrutiny simulations for an iowa corn producer confirm the comparative statics

the pricing of call and put options on foreign exchange this paper derives pricing equations for european puts and calls on foreign exchange the call and put pricing formulas are unlike the black scholes equations for stock options in that there are two relevant interest rates interest rates are stochastic and boundary constraints differ in addition it is shown that both american call and put options have values larger than their european counterparts

pricing contingent claims under interest rate and asset price risk this paper presents a general framework for pricing contingent claims under interest rate and asset price uncertainty the framework extends ho and lee s 1986 valuation framework by allowing not only future interest rates but also future asset prices to depend on the current term structure of interest rates the approach is shown to provide risk neutral valuation relationships that are consistent with the initial term structure of interest rates and can be applied to valuation of a broad class of assets including stock options convertible bonds and junk bonds

a nonparametric analysis of agricultural technology u s agricultural technology and technical change are analyzed nonparametrically under cost minimization and profit maximization based on annual data for 1948 83 various separability hypotheses concerning the aggregate production function for u s agriculture are investigated the proposed nonparametric approach also provides some insights into the nature of technical change

measurement errors and monetary policy then and now should policymakers and applied macroeconomists worry about the difference between real time and final data we tackle this question by using a bayesian var with time varying parameters and stochastic volatility to show that the distinction between real time data and final data matters for the impact of monetary policy shocks the impact on final data is substantially and systematically different in particular larger in magnitude for different measures of real activity from the impact on real time data these differences have persisted over the last 40 years and should be taken into account when conducting or studying monetary policy

an econometric analysis of the effects of human capital on size and growth among dairy farms the analysis of size distributions of firms has long been important both inside and outside of agriculture the study of farm size has focused on economies of scale optimal efficient size technical change descriptions of distributions and informal considerations of policy outside of farming the emphasis has been on the relationships between size and growth in both literatures there has been some awareness of the role of the firm operator in firm size and growth in this paper we examine herd size and herd growth for a large sample of southern dairy farms our emphasis is on the relationship of human capital of the operator to the crosssectional size and growth patterns other related work considers size growth issues in more detail sumner and leiby our research relates to several literatures that have evolved along distinct paths these include the analysis of the size distribution of farms see stanton the role of human capital in agriculture and earnings distributions and the analysis of the size distribution of business firms

data revisions and the identification of monetary policy shocks abstract monetary policy research using time series methods has been criticized for using more information than the federal reserve had available to quantify the role of this criticism we estimate vars with real time data while accounting for the latent nature of many economic variables such as output our estimated monetary policy shocks are closely correlated with typically estimated measures the impulse response functions are broadly similar across estimation methods our evidence suggests that the use of revised data in var analyses of monetary policy shocks may not be a serious limitation for recursively identified systems but presents more challenges for simultaneous systems

does the law of one price really hold for commodity prices in spite of the empirical failure of the law of one price it is usually assumed that commodity prices are perfectly arbitraged at least in the long run this paper argues that this assumption is counterfactual and that much of the empirical evidence provided to support it is flawed and affected by econometric shortcomings spurious regressions nonstationarity in the data inappropriate use of first differences an alternative methodology co integration by which a long run relationship between nonstationary series can be tested is proposed tests of nonstationarity and co integration for a group of commodities show quite uniformly that the law of one price as a long run relationship fails and that deviations from the pattern are permanent

productivity growth technical progress and efficiency change in industrialized countries this paper analyzes productivity growth in 17 oecd countries over the period 1979 1988 a nonparametric programming method activity analysis is used to compute malmquist productivity indexes these are decomposed into two component measures namely technical change and efficiency change we find that u s productivity growth is slightly higher than average all of which is due to technical change japan s productivity growth is the highest in the sample with almost half due to efficiency change jel c43 d24 in this paper we apply recently developed

profit maximization returns to scale and measurement error a nonparametric analysis of agricultural production behavior was conducted for each of the contiguous forty eight states for the period 1956 82 under the joint hypothesis of profit maximization convex technology and nonregressive technical change tests were conducted in each state for profit maximization and for constant returns to scale although considerable variability was observed among states measurement errors of magnitudes common in secondary data yielded test results fully consistent with the profit maximization hypothesis in all states with complete output and input data copyright 1992 by mit press

real time forecasting of inflation and output growth with autoregressive models in the presence of data revisions we examine how the accuracy of real time forecasts from models that include autoregressive terms can be improved by estimating the models on lightly revised data instead of using data from the latest available vintage the benefits of estimating autoregressive models on lightly revised data are related to the nature of the data revision process and the underlying process for the true values empirically we find improvements in root mean square forecasting error of 2 4 when forecasting output growth and inflation with univariate models and of 8 with multivariate models we show that multiple vintage models which explicitly model data revisions require large estimation samples to deliver competitive forecasts copyright 2012 john wiley sons ltd

pitfalls in testing for explosive bubbles in asset prices a number of studies e g robert j shiller 1981 olivier j blanchard and mark watson 1982 kenneth d west 1988 have argued that dividend and stock price data are not consistent with the market fundamentals hypothesis in which prices are given by the present discounted values of expected dividends these results have often been construed as evidence for the existence of bubbles or fads related arguments have been made with respect to gold bonds and foreign exchange a major problem with such arguments e g james hamilton and charles whiteman 1985 is that apparent evidence for bubbles can be reinterpreted in terms of market fundamentals that are unobserved by the researcher behzad t diba and herschel i grossman 1984 1988b and hamilton and whiteman 1985 have recommended the alternative strategy of testing for rational bubbles by investigating the stationarity properties of asset prices and observable fundamentals 1 in essence the argument for equities is that if stock prices are not more explosive than dividends then it can be concluded that rational bubbles are not present since they would generate an explosive component to stock prices 2 using unit root tests autocorrelation patterns and cointegration tests to implement this procedure diba and grossman 1988b p 529 state that the analysis supports the conclusion that stock prices do not contain explosive rational bubbles this paper shows that the above battery of tests is in fact unable to detect an important class of rational bubbles the point is demonstrated by constructing rational bubbles that appear to be stationary when unitroot tests are applied even though they are explosive in the relevant sense simulations show that when such bubbles are present stock prices will not appear to be more explosive than dividends on the basis of these tests even though the bubbles are substantial in magnitude and volatility the presence of rational bubbles in actual stock prices thus remains an open question

the valuation of options on futures contracts rational restrictions are derived for the values of american options on futures contracts for these options the optimal policy in general involves premature exercise a model is developed for valuing options on futures contracts in a constant interest rate setting despite the fact that premature exercise may be optimal the value of this american feature appears to be small and a european formula due to black serves as a useful approximation finally a model is developed to value these options in a world with stochastic interest rates it is shown that the pricing errors caused by ignoring the location of the interest rate relative to its long run mean range from 5 to 7 when the current rate is 200 basis points from its long run value the role of interest rate expectations is therefore crucial to the valuation optimal exercise policies are found from numerical methods for both models in recent years there has been a steady growth in the number of financial assets which one might properly call derivative assets that are available for trading on the organized exchanges among these the most recent and notable are options contracts written on available futures contracts options are now traded on the futures contracts on stock market indexes on the futures contracts on treasury instruments on the futures contracts on foreign exchange rates and on the futures contracts on some metals in design these options contracts do not differ substantially from the well known options contracts on common stock except that the underlying asset is a futures contract the received theory of the valuation of these options suggests that such contracts provide a direct vehicle for investors to alter the terminal payoffs on their portfolios to a desired distribution in the absence of these contracts investors would be forced to pursue a dynamic portfolio policy at the expense of considerable transactions in order to achieve a similar distribution indeed the availability of put options on the futures contracts on stock market indexes now enables well diversified investors to purchase portfolio insurance in his seminal work black 1 provided a complete description of forward and futures contracts as well as the description and valuation of european options on forward contracts and on spot commodities breeden 3 has examined the use of commodity options in a theoretical framework and courtadon 6 has studied the valuation of options on treasury bond futures french 13 cox