understanding the effect of technology shocks in svars with long run restrictions this paper studies the statistical properties of impulse response functions in structural vector autoregressions svars with a highly persistent variable as hours worked and long run identifying restrictions the highly persistent variable is specified as a nearly stationary persistent process such process appears particularly well suited to characterized the dynamics of hours worked because it implies a unit root in finite sample but is asymptotically stationary and persistent this is typically the case for per capita hours worked which are included in svars theoretical results derived from this specification allow to explain most of the empirical findings from svars which include u s hours worked simulation experiments from an estimated dsge model confirm theoretical results

the economics of a blend mandate for biofuels a biofuel blend mandate may increase or decrease consumer fuel prices with endogenous oil prices depending on relative supply elasticities biofuel tax credits always reduce fuel prices tax credits result in lower fuel prices than under a mandate for the same level of biofuel production if tax credits are implemented alongside mandates then tax credits subsidize fuel consumption instead of biofuels this contradicts energy policy goals by increasing oil dependency co 2 emissions and traffic congestion while providing little benefit to either corn or ethanol producers these social costs will be substantial with tax credits costing taxpayers 28 7 billion annually by 2022 copyright 2008 oxford university press

tracking the new economy using growth theory to detect changes in trend productivity abstract the acceleration of productivity after 1995 prompted a debate over whether the economy s underlying growth rate would remain high in this paper we draw on growth theory to identify variables other than productivity namely consumption and labor compensation to help estimate trend productivity growth we treat that trend as a common factor with two regimes high and low growth our analysis picks up striking evidence of a return in 1997 to the high growth regime nearly 25 years after a switch from high to low growth we find that both the common factor and regime switching aspects of the model are important for identifying changes in trend productivity and also show that the trend breaks are more difficult to detect with per capita as opposed to per hour based data because of persistent labor supply shifts finally we argue that our methodology is effective in detecting changes in trend in real time in the case of the 1990s the methodology would have signaled the regime switch by 1999 or within roughly six quarters of when it occurred according to the full sample

correlations between biofuels and related commodities before and during the food crisis a taxonomy perspective abstract in this paper we analyze the relationships between the prices of biodiesel ethanol and related fuels and agricultural commodities with a use of minimal spanning trees and hierarchical trees to distinguish between short term and medium term effects we construct these trees for different frequencies weekly and monthly we find that in short term both ethanol and biodiesel are very weakly connected with the other commodities in medium term the biofuels network becomes more structured the system splits into two well separated branches a fuels part and a food part biodiesel tends to the fuels branch and ethanol to the food branch when the periods before and after the food crisis of 2007 2008 are compared the connections are much stronger for the post crisis period this is the first application of this methodology on the biofuel systems

how the baby boomers retirement wave distorts model based output gap estimates hours per capita measures based on the private sector as usually included in the set of observables for estimating macroeconomic models are affected by low frequent demographic trends and sectoral shifts that cannot be explained by standard models further model based output gap estimates are closely linked to the observable hours per capita series hence hours per capita that are not measured in concordance with the model assumptions can distort output gap estimates this paper shows that sectoral shifts in hours and the changing share of prime age individuals in the working age population lead indeed to erroneous output gap dynamics regarding the aftermath of the global financial crisis model based output gaps estimated using standard hours per capita series are persistently negative for the us economy this is not caused by a permanently depressed economy but by the retirement wave of baby boomers which lowers aggregate hours per capita after adjusting hours for changes in the age composition to bring them in line with the model assumptions the estimated output gap gradually closes in the years following the global financial crisis

value at risk estimation with the optimal dynamic biofuel portfolio abstract in the past petroleum companies only paid attention to hedging the variation in the crude oil price and volatility however they have now expanded their analysis to encompass renewable sources such as corn and soybeans under the current low carbon biofuel obligations this paper employs garch 1 1 and arji models to estimate the one day ahead value at risk var of the optimal dynamic biofuel portfolio which consists of crude oil corn and soybeans the optimal blended standard is subject to the dual limitations of minimum production costs and the lowest biofuel using requirements our empirical findings confirm that the arji model is more suitable than the garch 1 1 model and further captures the discontinuous jump behavior from the in the sample data the results of out of sample forecasts also are represented that our models play important roles in var estimation and risk management for biofuel portfolio we therefore suggest that the petroleum companies should simultaneously pay attention to jump risk in hedging material costs in the prices of energy related crops

consumer demand and the life cycle allocation of household expenditures the purpose of this paper is to estimate the parameters of household preferences that determine the allocation of goods within the period and over the life cycle using micro data in doing so the authors are able to identify important effects of demographics labor market status and other household characteristics on the intertemporal allocation of expenditure they test the validity of the life cycle model using excess sensitivity tests and find that controlling for demographics and labor market status variables can largely explain the excess sensitivity of consumption to anticipated changes in income

unemployment and productivity in the long run the role of macroeconomic volatility abstract this paper presents a new empirical regularity between the volatility of productivity growth and long run unemployment for a given level of long run productivity growth a theoretical framework based on asymmetric real wage rigidities is shown to have the potential to rationalize this finding the model tends to fit u s long run unemployment better than a specification based on long run productivity growth only especially during the great moderation and the great recession

dynamic almost ideal demand systems an empirical analysis of alcohol expenditure in ireland this paper presents a dynamic form of the almost ideal demand system aids three versions of the static aids model are employed to determine the preferred long run equilibrium model and represents the short run dynamics by an error correction mechanism this estimation procedure is then applied to alcohol expenditure in ireland the estimated point elasticities are consistent with previous studies and a priori expectations beer and spirits are found to be price inelastic in both the short and long run while wine is price inelastic in the short run and price elastic in the long run

testing the technology interpretation of news shocks this article presents further evidence on the hypothesis of news driven business cycles i use a structural vector error correction model vecm approach to identify news shocks as in beaudry and lucke bl 2010 i document three facts first news shocks identified by bl are granger causal for us patent data second bl s analysis applied to german macro data reveals very similar patterns activity is largely driven by news and news shocks explain a sizable and increasing share of total factor productivity tfp variance at long horizons and third german news shocks are granger causal for german patent data and the pattern is again very similar to the us since patent data in the us and germany are almost uncorrelated the similarity is striking and strongly suggests a technology interpretation of news shocks

factor demand linkages technology shocks and the business cycle abstract this paper argues that factor demand linkages can be important for the transmission of both sectoral and aggregate shocks we show this using a panel of highly disaggregated manufacturing sectors together with sectoral structural vars when sectoral interactions are explicitly accounted for a contemporaneous technology shock to all manufacturing sectors implies a positive response in both output and hours at the aggregate level otherwise there is a negative correlation as in much of the existing literature furthermore we find that technology shocks are important drivers of the business cycle

identification of technology shocks using misspecified vars studies that evaluate the effects of technology shocks often employ structural vars identified with long run restrictions in the presence of a mismatch between the lag structures of the true data generating process and the adopted var estimates based on long run restrictions can be biased this paper offers a method that can reduce this bias substantially using artificial data i assess the performance of the proposed method and find that it can outperform a range of alternative procedures applying the procedure to the us data i find that per capita hours exhibit a positive hump shaped response profile in response to a technology shock resume identification des chocs technologiques a l aide de vecteurs autoregressifs mal specifies des etudes pour evaluer les effets de chocs technologiques emploient souvent des modeles de vecteurs autoregressifs var structurels avec des restrictions a long terme quand il n y a pas d arrimage entre les structures de delais du processus generant les vraies donnees et celles qui emergent des modeles var adoptes les estimes bases sur les restrictions a long terme peuvent etre biaises ce texte propose une methode qui peut reduire ce biais de maniere substantielle a partir de donnees artificielles on evalue la methode proposee et on montre qu elle performe mieux que les procedures de rechange en appliquant cette methode aux donnees americaines on decouvre un profil positif en forme de bosse dans les heures de travail per capita en reponse a un choc technologique

demand systems estimation with microdata a censored regression approach demand systems estimation increasingly makes use of household level microdata mainly to measure the effects of demographic variables data based on these household expenditure surveys present a major estimation problem for any given household many of the goods have zero consumption implying a censored dependent variable techniques which do not take this censored dependent variable into account will yield biased results we utilize a censored regression approach that is computationally simple consistent and asymptotically efficient the results are then presented and compared with those obtained using an uncensored technique

a flexible finite horizon alternative to long run restrictions with an application to technology shocks abstract recent studies using long run restrictions question the validity of the technology driven real business cycle hypothesis we propose an alternative identification that maximizes the contribution of technology shocks to the forecast error variance of labor productivity at a long but finite horizon in small sample monte carlo experiments our identification outperforms standard long run restrictions by significantly reducing the bias in the short run impulse responses and raising their estimation precision unlike its long run restriction counterpart when our max share identification technique is applied to u s data it delivers the robust result that hours worked responds negatively to positive technology shocks

the dynamics of hours worked and technology the response of hours worked to technology shocks in the postwar us economy has increased over time we offer a structural interpretation of this important time varying macroeconomic moment the time varying patterns captured by a structural var are consistent with those obtained from a parsimonious rbc model with a less than unitary elasticity of substitution between capital and labour the observed changes in the response of hours are attributable to increases in the magnitude of the degree of capital labour substitution finally we conjecture that the observed time variation in is related to changes in the skill composition of the work force and biases in technological change

the cyclical behavior of the price cost markup countercyclical markups constitute the key transmission mechanism for monetary and other demand shocks in new keynesian models this paper tests the foundation of those models by studying the cyclical properties of the markup of price over marginal cost the first part of the paper studies markups in the aggregate economy and the manufacturing sector we use bils s 1987 insights for converting average cost to marginal cost but do so with richer data we find that all measures of markups are either procyclical or acyclical moreover we show that monetary shocks lead markups to fall with output the second part of the paper merges input output information on shipments to the government with detailed industry data to study the effect of demand changes on industry level markups industry level markups are found to be acyclical in response to demand changes

current real business cycle theories and aggregate labor market fluctuations hours worked and the return to working are weakly correlated traditionally the ability to account for this fact has been a litmus test for macroeconomic models existing real business cycle models fail this test dramatically we modify prototypical real business cycle models by allowing government consumption shocks to influence labor market dynamics this modification can in principle bring the models into closer conformity with the data our empirical results indicate that it does

expectations learning and business cycle fluctuations this paper explores an alternative theory based on learning dynamics in the con text of an otherwise standard stochastic growth model we consider an environment in which households and firms have an incomplete model of the macroeconomy knowing only their own objectives constraints and beliefs agents are optimizing have a completely specified belief system but do not know the equilibrium map ping between primitive disturbances the aggregate state of the economy and mar ket clearing prices by extrapolating from historical patterns in observed data they approximate this mapping to forecast variables that are exogenous to their decision problems such as the rental rate of capital and the real wage this belief structure has the property that beliefs affect the true data generating process of the economy which in turn affects belief formation the economy is therefore self referential shifts in beliefs about future returns to labor and capital affect current market clear ing prices which in turn can reinforce beliefs in this environment current prices can become less informative about future economic conditions generating fluctuations in real activity this kind of mechanism driving business cycle fluctuations is found in early writ ings on macroeconomic dynamics for example alfred c pigou 1927 on page 122 writes

the cyclical and secular behaviour of the labour input comparing efficiency units and hours worked summary a monthly labour input series designed to correct for the fact that all hours worked are not of the same quality is constructed and its properties compared with unadjusted hours worked this efficiency units series is constructed from bls data on hours worked and earnings by age and sex the cyclical fluctuations displayed by the efficiency units series are smaller on average than those displayed by hours worked although the difference is not large however the secular behaviour of the series is quite different hours worked per capita displays a significant positive trend while efficiency units per capita does not

consumption heterogeneity employment dynamics and macroeconomic co movement abstract real business cycle models rely on total factor productivity tfp shocks to explain the observed co movement among consumption investment and hours however an emerging body of evidence identifies investment shocks as important drivers of business cycles this paper shows that a neoclassical model consistent with observed heterogeneity in labor supply and consumption across employed and non employed can generate co movement in response non tfp shocks estimation reveals fluctuations in the marginal efficiency of investment that explain the bulk of business cycle variance in consumption investment and hours a corollary of the model s empirical success is the labor wedge that is not important at business cycle frequencies

measures of per capita hours and their implications for the technology hours debate structural vector autoregressions give conflicting results on the effects of technology shocks on hours the results depend crucially on the assumed data generating process for hours per capita we show that the standard measure of hours per capita and productivity have significant low frequency movements that are the source of the conflicting results hodrick prescott hp filtered hours per capita produce results consistent with those obtained when hours are assumed to have a unit root we show that important sources of the low frequency movements in the standard measure are sectoral shifts in hours and the changing age composition of the working age population when we control for these low frequency components to determine the effect of technology shocks on hours using long run restrictions we get one consistent answer hours decline in the short run in response to a positive technology shock we further extend the analysis by examining the effects of demographic controls on the impulse responses to investment specific technology shocks our results are less conclusive

fiscal policy in the aftermath of 9 11 this paper investigates the nature of u s fiscal policy in the aftermath of 9 11 we argue that the recent declines in the government surplus and tax rates cannot be accounted for by either the state of the u s economy as of 9 11 or as the typical response of fiscal policy to a large exogenous rise in military expenditures our evidence suggests that had tax rates responded in the way they normally do to a large fiscal shock aggregate output would have been lower and the surplus would not have changed by much our results do not bear directly on the desirability of the decline in tax rates or the surplus after 9 11

stochastic trends and economic fluctuations are business cycles mainly the result of permanent shocks to productivity this paper uses a long run restriction implied by a large class of real business cycle models identifying permanent productivity shocks as shocks to the common stochastic trend in output consumption and investment to provide new evidence on this question econometric tests indicate that this common stochastic trend cointegration implication is consistent with postwar u s data however in systems with nominal variables the estimates of this common stochastic trend indicate that permanent productivity shocks typically explain less than half of the business cycle variability in output consumption and investment copyright 1991 by american economic association

comparing dsge var forecasting models how big are the differences abstract i generate priors for a vector autoregression var from a standard real business cycle rbc model an rbc model with capital adjustment costs and habit formation and a sticky price model with an unaccommodating monetary authority the response of hours worked to a tfp shock differs sharply across these models i compare the accuracy of forecasts made from each of the resulting dynamic stochastic general equilibrium vector autoregression dsge var models despite having different structural characteristics the dsge vars are comparable in terms of forecasting performance as in previous work dsge vars compare favorably with atheoretical vars

can long run restrictions identify technology shocks gali s innovative approach of imposing long run restrictions on a vector autoregression var to identify the effects of a technology shock has become widely utilized in this paper we investigate its reliability through monte carlo simulations using calibrated business cycle models overall gali s methodology appears to be fruitful the impulse responses derived from the artificial data generally have the same sign and qualitative pattern as the true responses and the approach can be informative in discriminating between alternative models however our results reveal some important quantitative shortcomings including considerable estimation uncertainty about the impact of technology shocks on macroeconomic variables more generally the conditions under which the methodology performs well appear considerably more restrictive than implied by the key identifying assumption this underscores the importance of using economic models to guide in the implementation of the approach in interpreting the results and in assessing its limitations jel c32 e32 o33

structural shocks and the comovements between output and interest rates stylized facts on u s output and interest rates have so far proved hard to match with simple dsge models i estimate covariances between output nominal and real interest rate conditional on structural shocks since such evidence has largely been lacking in previous discussions of the output interest rate puzzle conditional on shocks to technology and monetary policy the results square with simple models moreover permanent inflation shocks accounted for the counter cyclical and inversely leading behavior of the real rate during the great inflation 1959 1979 over the great moderation 1982 2006 technology shocks were more dominant and the real rate has been pro cyclical

risk premium shocks and the zero bound on nominal interest rates there appears to be a disconnect between the importance of the zero bound on nominal interest rates in the real world and predictions from quantitative dsge models recent economic events have reinforced the relevance of the zero bound for monetary policy whereas quantitative models suggest that the zero bound does not constrain optimal monetary policy

validating energy oriented cge models although cge models have received heavy usage they are often criticized as being insufficiently validated key parameters are often not econometrically estimated and the performance of the model as a whole is rarely checked against historical outcomes as a consequence questions frequently arise as to how much faith one can put in cge results in this paper we employ a novel approach to the validation of a widely utilized global cge model gtap e by comparing the variance of model generated petroleum price distributions driven by historical demand and supply shocks to the model with observed five year moving average price distributions we conclude that energy demand in gtap e is far too price elastic over this time frame after incorporating the latest econometric estimates of energy demand and supply elasticities we revisit the validation question and find the model to perform more satisfactorily as a further check we compare a deterministic global general equilibrium simulation based on historical realizations over the 2001 2006 period during which petroleum prices rose sharply along with growing global energy demands as anticipated by the stochastic simulations the revised model parameters perform much better than the original gtap e parameters in this global general equilibrium context

broken trend stationarity of hours worked the estimated impact of a technology shock on hours worked using structural vector autoregressions svars depends to a great extent on whether or not hours worked is considered to be integrated of first order it is shown in this article that the widely analysed time series of hours worked per capita in the us business sector evolves around a broken linear trend when this fact is taken into account the unit root null is rejected by recently proposed tests therefore it can be stated that empirical specifications with hours in first differences are not recommended it seems more appropriate to control for the presence of this shift in the deterministic component we also draw this conclusion from a bivariate model for both productivity growth and hours worked our results suggest that technology improvements have a negative but nonsignificant effect on hours only in the very short run this impact later becomes positive and statistically significant after five periods

evaluating point and density forecasts of dsge models this paper investigates the accuracy of point and density forecasts of four dsge models for inflation output growth and the federal funds rate model parameters are estimated and forecasts are derived successively from historical u s data vintages synchronized with the fed s greenbook projections point forecasts of some models are of similar accuracy as the forecasts of nonstructural large dataset methods despite their common underlying new keynesian modeling philosophy forecasts of different dsge models turn out to be quite distinct weighted forecasts are more precise than forecasts from individual models the accuracy of a simple average of dsge model forecasts is comparable to greenbook projections for medium term horizons comparing density forecasts of dsge models with the actual distribution of observations shows that the models overestimate uncertainty around point forecasts

factor hoarding and the propagation of business cycles shocks this paper analyzes the role of variable capital utilization rates in propagating shocks over the business cycle to this end we formulate and estimate an equilibrium business cycle model in which cyclical capital utilization rates are viewed as a form of factor hoarding we find that variable capital utilization rates substantially magnify and propagate the impact of shocks to agents environments the strength of these propagation effects is evident in the dynamic response functions of various economy wide aggregates to shocks in agents environments in the statistics that we construct to summarize the strength of the propagation mechanisms in the model and in the volatility of exogenous technology shocks needed to explain the observed variability in aggregate u s output other authors have argued that standard real business cycle rbc models fail to account for certain features of the data because they do not embody quantitatively important propagation mechanisms these features include the observed positive serial correlation in the growth rate of output the shape of the spectrum of the growth rate of real output and the correlation between the forecastable component of real output and various other economic aggregates allowing for variable capital utilization rates substantially improves the ability of the model to account for these features of the data

investment shocks and business cycles abstract the origins of business cycles are still controversial among macroeconomists this paper contributes to this debate by studying the driving forces of fluctuations in an estimated new neoclassical synthesis model of the u s economy in this model most of the variability of output and hours at business cycle frequencies is due to shocks to the marginal efficiency of investment imperfect competition and to a lesser extent technological frictions are the key to their transmission although labor supply shocks explain a large fraction of the fluctuations in hours at very low frequencies they are irrelevant over the business cycle this finding is important because the microfoundations of these disturbances are widely regarded as unappealing

volatility spillovers between food and energy markets a semiparametric approach previous literature on volatility links between food and energy prices is scarce and mainly based on parametric approaches this article examines these links by using a semiparametric garch model recently proposed by long et al 2011 which is essentially a nonparametric correction of the parametric conditional covariance function the analysis focuses on price links between crude oil ethanol and sugar prices in brazil results suggest strong volatility links between the prices studied parametric approximations of the conditional covariance matrix may lead to misleading results that can be improved upon by using nonparametric techniques

trend breaks long run restrictions and contractionary technology improvements abstract structural vector autoregressions with long run restrictions are extraordinarily sensitive to low frequency correlations recent literature finds that the estimated effects of technology shocks are sensitive to how one treats hours per capita however after allowing for statistically and economically significant trend breaks in productivity results are much less sensitive hours fall when technology improves the issue is that the common high low high pattern of productivity growth and hours i e the low frequency correlation inevitably leads to a positive estimated response the trend breaks control for this correlation this example suggests a practical need for care in using long run restrictions

what do technology shocks tell us about the new keynesian paradigm abstract researchers have used unanticipated changes to monetary policy to identify preference and technology parameters of macroeconomic models this paper uses changes in technology to identify the same set of parameters estimates based on technology shocks differ substantially from those based on monetary policy shocks in the post world war ii united states a positive technology shock reduces inflation and increases hours worked significantly and rapidly in both cases relative to policy shock identification technology shock identification implies i long duration durability in preferences instead of short duration habit ii built in inflation inertia disappears and price flexibility increases in response to technological improvement consumption durability increases hours worked because households temporarily increase labor supply to accumulate durables towards a new higher steady state level limited nominal rigidities allow inflation to fall because firms are able to immediately cut prices when households labor supply increases finally we consider alternative data constructions and econometric specifications we find that i and or ii hold in nearly every case

intangible capital and the rise in wage and hours volatility in a standard real business cycle model extended to include intangible capital ic i show that a rise in the income share of ic in the production function in line with data can account for a significant share of the increase in real wage volatility both absolute and relative to income and labor input volatility relative to income observed in the u s since the mid 1980 s even as volatility of output declined intangible capital accumulates stochastically and similar to final goods requires physical capital intangible capital and labor to produce under these conditions an increase in the share of ic in production increases the propagation of the ic specific shock which raises absolute and relative wage and labor input volatility the higher propagation of the ic shock also accounts for the large decline in the pro cyclicality of labor productivity relative to both output and labor observed during this period

slow recoveries a structural interpretation an analysis of the speed of recovery of employment unemployment and gdp following business cycle troughs in the postwar u s economy points to much slower recoveries in the three most recent episodes but does not reveal any signi cant change in the relation between gdp and employment or unemployment across recoveries this leads us to characterize the last three episodes as slow recoveries as opposed to jobless recoveries we use the estimated new keynesian model in gali smets wouters 2011 to provide a structural interpretation for the slower recoveries since the early nineties

food versus fuel what do prices tell us abstract sorting out the impacts of biofuels on global agricultural commodity prices is impossible without turning to data and distinguishing between the short run versus the long run impacts using time series prices on fuels and agricultural commodities the aim is to investigate the long run cointegration of these prices simultaneously with their multivariate short run interactions results indicate no direct long run price relations between fuel and agricultural commodity prices and limited if any direct short run relationships in terms of short run price movements sugar prices are influencing all the other agricultural commodity prices except rice with sugar the number one world input for ethanol results indicate increased ethanol production is potentially influencing short run agricultural commodity prices overall results support the effect of agricultural commodity prices as market signals which restore commodity markets to their equilibria after a demand or supply event shock

the response of hours to a technology shock a two step structural var approach the response of hours to a technology shock is a controversial issue in macroeconomics part of the difficulty lies in that the estimated response is sensitive to the specification of hours in structural vector autoregressions svars this paper uses a simple two step approach to consistently estimate the response of hours the first step considers a svar model with a relevant stationary variable but excluding hours given a consistent estimate of technology shocks in the first step the response of hours to this shock is estimated in a second step simulation experiments from an estimated dynamic stochastic general equilibrium dsge model show that this approach outperforms standard svars when applied to u s data the two step approach predicts a short run decrease followed by a hump shaped positive response this result is robust to other specifications and data

nonlinearities in the u s corn ethanol oil gasoline price system we use a smooth transition vector error correction model to assess price relationships within the u s ethanol industry monthly ethanol corn oil and gasoline prices from 1990 to 2008 are used in the analysis results indicate the existence of long run relationships among the prices analyzed strong links between energy and food prices are identified

sport event attendance as a function of education evidence from the uk abstractthis article studies the role of education in the decision to attend sporting events the overall objective is to verify whether more educated individuals are more likely to go to sports events than their less educated counterparts if education socializes persons to focus on sports it would then partially offset negative alternatives such as alcohol drug abuse and unlawful behaviours creating a positive externality sport events consumption is extensive highlighting the potential economic importance of the sports education externality to establish the role of education in sport attendance this article applies a probabilistic linear regression model to data from the uk the econometric formulation associates sport event attendance in the left hand side with education in the right hand side while controlling for the socioeconomic variables that are known to affect a consumer s decision to go to a sport event gender age income employment status children marital status and geographical

identifying a permanent markup shock and its implications for macroeconomic dynamics abstract a permanent price markup shock is justified using an industry based model in which an increase in market concentration raises the desired markup moreover evidence in favor of the non stationarity of the markup is presented which in turn implies that per capita hours are also non stationary structural vector autoregressions are then constructed that can identify shocks to the markup technology and the federal funds rate the results show that 1 inflation responds immediately to shocks to the markup and technology whereas it displays a hump shaped response to a monetary policy shock and that 2 per capita hours decline in response to positive shocks to the markup and technology these empirical findings have important implications for macroeconomic dynamics including the issues on inflation inertia and the technology hours debate the paper also points out that the dynamics of the economy cannot be correctly explained without consideration of the permanent markup shock finally the approach in this paper suggests several ways to identify a wage markup shock using structural vector autoregressions

are biofuels the culprit opec food and fuel the food commodity price boom of 2003 2008 was the most notable in the past several decades having a substantial impact on global economic activity it affected developing nations by impacting real output the balance of payments government budgetary positions and most important the well being of the very poor high commodity prices also affected developed countries by transmitting business cycle disturbances and creating inflationary pressures several recent studies tried to identify and quantify the factors that caused the food commodity price boom of 2003 2008 see for instance isabel vansteenkiste 2009 these studies suggest that one key factor is growth in demand which since the 1980s has outpaced growth in supply other studies argued that biofuel is the culprit since it increases demand for staple crops see for instance donald mitchell 2008 all these studies however assumed competitive markets and did not consider the impact of biofuel on energy costs to farmers moreover they ignored the organization of petroleum exporting countries opec these studies leave us perplexed regarding the true impact of biofuel on food commodity prices was it or was it not an important contributor to the recent food commodity boom we believe that to answer this question the interactions between energy and food must be modeled and opec introduced and the impact of biofuels compared with other factors that are argued by the literature to be important this paper aims to analyze the multiple contributions of energy and biofuels to the increase are biofuels the culprit opec food and fuel

the impact of biofuels on commodity food prices assessment of findings for years agriculture has provided most of the fuel for vehicular transportation concerns about availability of fuels balance of trade and climate change led to the introduction of biofuel programs in the united states brazil europeanunion eu andothercountries the impacts of these programs and the relationship between the food and fuel markets have become major topics of economic research this paper summarizes the main findings of alternative lines of research on the relationship between the food and fuel markets and identifies gaps and quandaries that warrant further research this is not meant to be a complete survey and it emphasizes several of our studies within the broader literature the paper distinguishes between two bodies of literature one on the relationship between food and fuel prices and another on the impact of the introduction of biofuel on commodity food prices while biofuel prices do not seem to affect food commodity prices we explain why the introduction of biofuel does moreover biofuelshavenotbeenthemostdominant contributor to the recent food price inflation and different biofuels have different impacts

expenditure elasticities of the demand for leisure services although some research has already focused on the analysis of expenditure elasticities of leisure demand some shortcomings with regard to the content and the underlying theoretical model as well as the applied methods exist this article aims at avoiding these problems to provide consistent derivatives of leisure service expenditure elasticities therefore a regular demand system is derived from microeconomic duality theory to implement leisure specific demand factors i e demand and supply based sports and recreational opportunities as well as sports and recreational preferences while still being consistent with neoclassical demand theory the basic model is extended by applying the demographic translation framework data of the continuous household budget survey n 7724 from germany is used for the estimation of the derived demand system it is shown how sensitive the results are depending on the applied censored regression model 16 out of 18 analysed services are indicated as luxury goods b

three bubbles and a panic an explanatory review of recent food commodity price events abstract this paper is a summary of the behaviour of food commodity prices in 2007 2008 and a review of the causes of the price increases extracted from a report to the chief scientific advisor to her majesty s government thirtle c piesse j 2008 an explanatory review of the world food commodity price events of 2007 2008 a report to the chief scientific advisor department for innovation universities and skills london the historical background shows that the price spike was much less severe than in the 1970s the conventional wisdom that prices of the main food commodities were falling prior to 2006 is questioned most ceased falling and were quite stable from the 1980s the paper separates the causes of the spike from the underlying changes driving the long run trends the literature on the causes of the spike is critically reviewed and summarised there is a reasonably broad consensus on most of the causes but much less on the impact of the depreciation of the us dollar there are also concluding speculations on the future

assessing the impact of us ethanol on fossil fuel markets a structural var approach abstract despite the growing importance of biofuels the effect of biofuels on fossil fuel markets is not fully understood we develop a joint structural vector auto regression var model of the global crude oil us gasoline and us ethanol markets to examine whether the us ethanol market has had any impact on global oil markets the structural var approach provides a unique method for decomposing price and quantity data into demand and supply shocks allowing us to estimate the distinct dynamic effects of ethanol demand and supply shocks on the real prices of crude oil and us gasoline ethanol demand in the us is driven mainly by government support in the form of tax credits and blending mandates shocks to ethanol demand therefore reflect changes in policy more than any other factor in contrast ethanol supply shocks are driven by changes in feedstock prices a principle finding is that a policy driven ethanol demand expansion causes a statistically significant decline in real crude oil prices while an ethanol supply expansion does not have a statistically significant impact on real oil prices this suggests that even though us ethanol market is small the influence of us biofuels policy on the crude oil market is pervasive we also show that ethanol demand shocks are more important than ethanol supply shocks in explaining the fluctuation of real prices of crude oil and us gasoline

deriving conditional and unconditional marginal effects in log earnings equations estimated by heckman s procedure although the heckman approach has often been used in empirical analysis the marginal effects necessary to interpret the effect of the regressors on the dependent variable appeared to be overlooked using the heckman approach general expressions are derived for calculating the conditional and unconditional marginal effects based on a sample of brazilian women the conditional and unconditional return to education are calculated for the logarithm of earnings equation estimated by heckman s procedure comparing them to the marginal effect of education obtained without correcting for selectivity bias the same analysis is carried out for a discrete variable black

the welfare economics of a biofuel tax credit and the interaction effects with price contingent farm subsidies a framework is developed to analyze the effects of a biofuel consumer tax exemption and the interaction effects with a price contingent farm subsidy ethanol prices rise above the gasoline price by the amount of the tax credit corn farmers gain directly while gasoline consumers only gain from any reduction in world oil prices due to the extra ethanol production domestic oil producers lose historically the intercept of the ethanol supply curve is above the gasoline price hence part of the tax credit is redundant and represents rectangular deadweight costs that dwarf triangular deadweight cost measures of traditional farm subsidies copyright 2007 oxford university press

a sample selection approach to censored demand systems the multivariate sample selection model is extended to a nonlinear equation system with partial selection and applied to household meat consumption in china elasticity estimates differ from those obtained from conventional maximum likelihood and tobit estimates chinese meat products are gross complements while net substitution also exists in some cases the use of micro survey data has been popular in estimating consumer demand equations important features of microdata include censored dependent variables estimation procedures for censored consumer demand systems include the primal kuhn tucker approach of wales and woodland 1983 dual virtualprice approach of lee and pitt 1986 and the tobit system amemiya 1974 estimated by generalized maximum entropy golan perloff and shen 2001 and maximum simulated likelihood dong gould and kaiser 2004 yen lin and smallwood 2003 procedures less efficient alternatives include the quasi maximum likelihood estimator yen lin and smallwood 2003 the generalized method of moments estimator meyerhoefer ranney and sahn 2005 and a number of two step estimators heien and wessells 1990 perali and chavas 2000 shonkwiler and yen 1999 yen 2005 recently proposed a maximum likelihood ml procedure for the multivariate sample selection model mssm an extension of the bivariate sample selection model heckman 1979 which had motivated the procedures of heien and wessells 1990 and shonkwiler and yen 1999 the mssm was developed in the context of linear equations and in addition is not strictly applicable for a partially selective equation system viz

commodity price shocks and the business cycle structural evidence for the u s this paper evaluates the relative importance of commodity price shocks in the u s business cycle therefore we extend the standard set of business cycle shocks to include unexpected changes in commodity prices the resulting svar shows that commodity price shocks are a very important driving force of macroeconomic fluctuations second only to investment specific technology shocks particularly with respect to inflation neutral technology shocks and monetary policy shocks on the other hand seem less relevant at business cycle frequencies neutral technology shocks rather play an important role at low frequencies

hours per capita and productivity evidence from correlated unobserved components models recent studies debate the effect of a permanent productivity shock on hours per capita within a structural var context this paper examines the issue using a correlated unobserved components uc framework the estimates show that permanent shocks to productivity are negatively correlated with transitory shocks to hours this result is robust for non stationary or levels stationary specifications of hours model comparisons indicate that the data do not favor imposing var type restrictions on the uc models copyright 2008 john wiley sons ltd

the role of technology and nontechnology shocks in business cycles this article proposes a method to identify technology and nontechnology shocks that permanently affect labor productivity and applies this method to data for the g7 countries in most cases whereas technology improvements have negative or weak effects on hours worked positive permanent nontechnology shocks are expansionary permanent nontechnology shocks play an important role in business cycles particularly in the united states and japan and account for 71 of a large reduction in japan s detrended output from 1991 to 2002 credit conditions are likely to be an important driver of variations in permanent nontechnology shocks

interpreting aggregate fluctuations looking at sectors abstract a dynamic factor model is used to investigate on the variability in labor productivity and hours across the 2 digit us manufacturing industries two kind of shocks emerge as quantitatively relevant during the postwar period they can be reasonably interpreted as technology shocks to the production of equipment and economy wide shocks the former induces a positive correlation between productivity and hours growth rates in the durable goods producing sector the latter spurs a negative correlation in the nondurable goods producing sector such evidence provides a novel interpretation of the aggregate near zero correlation between the two variables

vegetable oil market and biofuel policy an asymmetric cointegration approach abstract the present paper analyses the long run relationship between vegetable oil prices and conventional diesel prices in the eu for the period 2005 2007 we applied recent developments in the threshold cointegration approach to investigate the presence of asymmetric dynamic adjusting processes between the prices of rapeseed oil sunflower oil and soybean oil and the price of a mineral oil diesel the results presented suggest a two regime threshold cointegration model only for the rapeseed oil diesel price pair thus the rapeseed oil price adjusts rapidly to its long run equilibrium determined by fossil diesel prices but this adjustment is asymmetric it differs if the divergence between the two prices is above or below a critical threshold consequently rapeseed oil appears particularly exposed to external shocks deriving from global political scenarios suggesting the reassessment of the high quota 80 of eu biodiesel represented by this vegetable oil

sensitivity of impulse responses to small low frequency comovements reconciling the evidence on the effects of technology shocks this article clarifies the empirical source of the debate on the effect of technology shocks on hours worked we find that the contrasting conclusions from levels and differenced vector autoregression specifications documented in the literature can be explained by a small low frequency comovement between hours worked and productivity growth that gives rise to a discontinuity in the solution for the structural coefficients identified by long run restrictions whereas the low frequency comovement is allowed for in the levels specification it is implicitly set to 0 in the differenced vector autoregression consequently even when the root of hours is very close to 1 and the low frequency comovement is quite small removing it can give rise to biases of sufficient size to account for the empirical difference between the two specifications

identification of technology shocks in structural vars the usefulness of svars for developing empirically plausible models is actually subject to controversies in macroeconomics we propose a two step svars based procedure which consistently estimates the effect of permanent technology shocks on aggregate variables simulation experiments from a standard business cycle model and a sticky prices model show that our approach outperforms standard svars the two step procedure when applied to actual data predicts a significant short run decrease of hours after a technology improvement followed by a hump shaped positive response additionally the rate of inflation and the nominal interest rate displays a significant decrease after this shock

the dynamic effects of neutral and investment specific technology shocks the neoclassical growth model is used to identify the short run effects of neutral technology shocks which affect the production of all goods homogeneously and investment specific shocks which affect only investment goods the real equipment price crucial for identifying the investment shocks experiences an abrupt increase in its average rate of decline in 1982 so the analysis is based on a split sample on the basis of the preferred specification the two technology shocks account for 73 percent of hours and 44 percent of output s business cycle variation before 1982 and 38 percent and 80 percent afterward the shocks also account for more than 40 percent of hours and 58 percent of output s forecast errors over a three to eight year horizon in both samples the majority of these effects are driven by the investment shocks

determinants of household expenditures for services data from the bureau of labor statistics consumer expenditure surveys were used to investigate factors influencing household expenditures for services in the united states there were significant differences between families with full time and part time working wives in expenditures on child care food away from home and total services household production variables had a significant impact on service expenditures in most instances while the effects of other variables such as family life cycle education race and geographic location varied by service category and employment status of wife

fiscal policy and lending relationships this paper studies how fiscal policy affects loan market conditions in the us first it conducts a structural vector autoregression analysis showing that the bank spread responds negatively to an expansionary government spending shock while lending increases second it illustrates that these results are mimicked by a dynamic stochastic general equilibrium model where the bank spread is endogenized via the inclusion of a banking sector exploiting lending relationships third it shows that lending relationships represent a friction that generates a financial accelerator effect in the transmission of the fiscal shock