the quantitative analytics of the basic neomonetarist model this paper constructs a dynamic macroeconomic model with less than perfect price flexibility which has a classical side consistent with real business cycle theory augmented by investment adjustment costs increasing returns to scale and a new flexible formalization of imperfect competition something akin to the classical dichotomy is justified by a mode of approximation appropriate for a model in which one state variable adjusts quickly while another state variable adjusts slowly even with investment adjustment costs monetary expansions are found to raise the real interest rate the determinants of real rigidity and the macroeconomic rate of price adjustment are investigated copyright 1995 by ohio state university press

who provides the capital for chinese growth the public or the private sector we focus on the role of the government in the provision of investment in china through the medium of a dynamic stochastic general equilibrium model of the economy in which the form of the production function reflects this governmental role using indirect inference we estimate and test for the elasticity of substitution between government and nongovernment capital in both constant elasticity of substitution ces and cobb douglas technologies the results underscore the strong substitution relationship between government and nongovernment capital from 1949 supporting ces rather than the cobb douglas technology they also show that the orientation of public investment changed after the start of the socialist market economy in 1992 government capital became more complementary to nongovernment capital as it focused more on infrastructure and withdrew from industrial production intervening only in times of crisis for stabilization purposes indirectly via the state banks

optimal economic dispatch and risk management of thermal power plants in deregulated markets this paper presents a methodology for the valuation optimization market margin and credit risk management of gas fired power plants and associated tolling contracts term structure models for the power and gas forward curves are employed to facilitate hedging and risk adjustment and for improved forecasting of short term prices the model for the power forward curve is capable of reproducing the important phenomena often observed in power markets including spot price spikes and spike clustering negative prices and the empirically observed volatility term structures of power and gas forward prices as well as the correlation term structure between these forward curves the method solves the stochastic dynamic optimization problem that arises from the inclusion of the various operational constraints of gas fired power plants including minimum uptime and downtime requirements ramp rate restrictions and costs variable output and efficiency rates and minimum generation levels the model involves the so

new keynesian models durable goods and collateral constraints abstract econometric evidence suggests that in response to monetary policy shocks durable and non durable spending co move positively and durable spending exhibits a much larger sensitivity to the shocks a standard two sector new keynesian model with perfect financial markets is at odds with these facts the introduction of a borrowing constraint where durables play the role of collateral assets helps in reconciling the model with the empirical evidence

a long commodity cycle model of the world economy over a century and a half making bricks with little straw abstract this paper explores the world business cycle using unfiltered data from 1870 and looks for a theory that could account for the long wave commodity cycle in the world economy we build a simple dsge model that includes a long time to build constraint in the commodity sector we find that this model can produce long cycles in output and commodity prices as introduced by kontradieff 1925 and schumpeter 1934 our findings show that these long business cycles are produced by the long gestation of commodity capacity which causes very large swings in commodity prices

tracing the causes of the banking crisis we add the bernanke gertler gilchrist model to a modified version of the smets wouters model of the u s in order to explore the causes of the banking crisis the innovation of this article is estimating the model using unfiltered data allowing for non stationary shocks in order to replicate how the model predicts the crisis we find that traditional shocks account for most of the fluctuations in macroeconomic variables the non stationarity of the productivity shock plays a key role crises occur when there is a run of bad shocks based on this sample they occur on average once every 64 years and when they occur around 10 are accompanied by financial crisis financial shocks on their own even when extreme do not cause crises provided the government acts swiftly to counteract such a shock as happened in this sample

housing market heterogeneity in a monetary union this paper studies the implications of cross country housing market heterogeneity in a monetary union for both shock transmission and welfare i develop a two country new keynesian general equilibrium model with housing and collateral constraints to explore this issue the conventional wisdom is that welfare would be higher in a monetary union if mortgage markets were homogeneous this paper shows instead that welfare is higher only when homogenization does not result in higher aggregate volatility because of financial accelerator effects or does not redistribute too much wealth from borrowers to savers

honey the currency union effect on trade hasn t blown up as the value of real bilateral trade between countries i and j at time t cu is a dummy variable which is unity if i and j sharethe same currency at time t z is a vector of controls given by an augmentedgravity model c are the associate nuisance coefficients and is a hopefully well behaved residual my chief finding was that was large and robust mypoint estimate was 1 2 implying that currency union is associated with atripling since exp 1 2 3 of trade in his paper in this issue volker nitsch provides three pieces of value added first he finds and corrects a number of data errors in my original data set second he shows that adding extra controls to my empirical setup disaggregating bycurrency unions and adjusting for missing data affects the results he concludesthat the effect of currency union on trade is smaller than my original estimates has not been reliably estimated and may be zero

uncertainty management in the unit commitment problem uncertainty in power systems operations has been traditionally managed by multistage decision making and operating reserve requirements a familiar example of multistage decisions is day ahead unit commitment and real time economic dispatch an alternate approach for managing uncertainty is a stochastic formulation which allows the explicit modeling of the sources of uncertainty this paper compares stochastic and reserve methods and evaluates the benefits of a combined approach for the efficient management of uncertainty in the unit commitment problem numerical studies show that unit commitment solutions obtained for the combined approach are robust and superior with respect to the traditional approach in terms of both economics and reliability metrics

incorporating fuel constraints and electricity spot prices into the stochastic unit commitment problem the electric power industry is going through deregulation as a result the load on the generating units of a utility is becoming increasingly unpredictable furthermore electric utilities may need to buy power or sell their production to a power pool that serves as a spot market for electricity these trading activities expose utilities to volatile electricity prices in this paper we present a stochastic model for the unit commitment that incorporates power trading into the picture our model also accounts for fuel constraints and prices that may vary with electricity prices and demand the resulting model is a mixed integer program that is solved using lagrangian relaxation and bender s decomposition using this solution approach we solve problems with 729 demand scenarios on a single processor to within 0 1 of the optimal solution in less than 10 minutes our numerical results indicate that significant savings can be achieved when the spot market is entered into the problem and when stochastic policy is adopted instead of a deterministic one

a characterization of ramsey equilibrium abstract consider a perfect foresight equilibrium model with a single capital good a borrowing constraint and many infinitely lived households with fixed but different discount factors the steady state capital stock is held by the most patient household quart j econ 95 1980 375 382 econ j 38 1928 543 559 an example shows the total capital can exhibit an equilibrium cycle in contrast to the stability property of the one household case in the example only the most patient household saves and his income deceases in capital we give a condition implying income is increasing in capital and use it to show any equilibrium converges to the steady state

slow information diffusion and the inertial behavior of durable consumption this paper studies the aggregate dynamics of durable and nondurable consumption under slow information diffusion sid due to noisy observations and learning within the permanent income framework we show that sid can significantly improve the model s predictions on the joint behavior of income durable consumption and nondurable consumption at the aggregate level specifically we find that sid can significantly improve the model s predictions for i smoothness in durable and nondurable consumption ii autocorrelation of durable consumption and iii contemporaneous correlation between durable and nondurable consumption furthermore we discuss that incorporating a fixed cost into our sid model does a better job of reproducing the infrequent adjustments of durable consumption at the individual level and the slow adjustments at the aggregate level

a bayesian approach to optimal monetary policy with parameter and model uncertainty abstract this paper undertakes a bayesian analysis of optimal monetary policy for the u k we estimate a suite of monetary policy models that include both forward and backward looking representations as well as large and small scale models we find an optimal simple taylor type rule that accounts for both model and parameter uncertainty for the most part backward looking models are highly fault tolerant with respect to policies optimized for forward looking representations while forward looking models have low fault tolerance with respect to policies optimized for backward looking representations in addition backward looking models often have lower posterior probabilities than forward looking models bayesian policies therefore have characteristics suitable for inflation and output stabilization in forward looking models

optimal monetary policy with durable consumption goods abstract we document that the durable goods sector is much more interest sensitive than the nondurables sector and then investigate the implications of these sectoral differences for monetary policy we formulate a two sector general equilibrium model that is calibrated both to match the sectoral responses to a monetary shock derived from our empirical var and to imply an empirically realistic degree of sectoral output volatility and comovement while the social welfare function involves sector specific output gaps and inflation rates the performance of the optimal policy rule can be closely approximated by a simple rule that targets a weighted average of aggregate wage and price inflation in contrast a rule that stabilizes a more narrow measure of final goods price inflation performs poorly in terms of social welfare

valuation and optimal operation of electric power plants in competitive markets we present an algorithm for the valuation and optimal operation of hydroelectric and thermal power generators in deregulated electricity markets real options theory is used to derive nonlinear partial integro differential equations pides for the valuation and optimal operating strategies of both types of facilities the equations are designed to incorporate a wide class of spot price models that can exhibit the same time dependent mean reverting dynamics and price spikes as those observed in most electricity markets particular attention is paid to the operational characteristics of real power generators for thermal power plants these characteristics include variable start up times and costs control response time lags minimum generating levels nonlinear output functions and structural limitations on ramp rates for hydroelectric units head effects and environmental constraints are addressed we illustrate the models with numerical examples of a pump storage facility and a thermal power plant this pide framework can achieve high levels of computational speed and accuracy while incorporating a wide range of spot price dynamics and operational characteristics

a stochastic programming approach to power portfolio optimization we consider a power portfolio optimization model that is intended as a decision aid for scheduling and hedging dash in the wholesale power market our multiscale model integrates the unit commitment model with financial decision making by including the forwards and spot market activity within the scheduling decision model the methodology is based on a multiscale stochastic programming model that selects portfolio positions that perform well on a variety of scenarios generated through statistical modeling and optimization when compared with several commonly used fixed mix policies our experiments demonstrate that the dash model provides significant advantages

risk constrained generation asset arbitrage in power systems a competitive generating company genco can maximize its payoff by optimizing its generation assets this paper considers the genco s arbitrage problem using stochastic price based unit commitment while considering the associated risks the genco may consider arbitrage opportunities in purchases from qualifying facilities qfs as well as simultaneous trades with spot markets for energy ancillary services fuel and emission allowance the tradeoff between maximizing expected payoffs and minimizing risks due to market price uncertainties is modeled explicitly by including the expected downside risk as a constraint the downside risk is defined as the unfulfilled profit the monte carlo simulation is applied to generate scenarios and scenario reduction techniques are applied to reduce the number of scenarios while maintaining a good approximation of the exact solution the proposed case studies illustrate the significance of arbitrage in multi commodity markets and the importance of considering the uncertainty of market prices

currency unions and trade the effect is large the impact of a common currency on trade can be grossly mismeasured if countries that belong to currency unions are systematically different from those that do not and if the relationship between trade and its observable determinants is complex i argue that such complications are plausible and likely to distort the empirical results of a recent economic policy paper by andrew rose issue 30 2000 pp 7 45 using techniques designed to be robust in this situation i find that the effects of common currency on international trade are considerably less dramatic and much less precisely estimated copyright cepr ces msh 2001

limited information estimation and evaluation of dsge models we advance the proposition that dynamic stochastic general equilibrium dsge models should not only be estimated and evaluated with full information methods these require that the complete system of equations be specified properly some limited information analysis which focuses upon specific equations is therefore likely to be a useful complement to full system analysis two major problems occur when implementing limited information methods these are the presence of forward looking expectations in the system as well as unobservable non stationary variables we present methods for dealing with both of these difficulties and illustrate the interaction between full and limited information methods using a well known model copyright 2009 john wiley sons ltd

is housing collateral important to the business cycle evidence from china abstract this paper investigates whether housing collateral is important to the business cycle in china we develop two models one without housing collateral as benchmark and one variant allowing for it indirect inference procedure tests these two models compatibility with the data we find that the benchmark model passes the test while the collateral model is strongly rejected according to the benchmark model shocks from the housing market have limited impact on the chinese business cycle by contrast the exogenous spending shock from government and net exports the monetary policy shock and the goods sector cost productivity shock all in turn most likely connected to world business cycle shocks especially the global financial crisis are found to be the main drivers

one money one market the effect of common currencies on trade currency unions their dramatic effect on international trade a gravity model is used to assess the separate effects of exchange rate volatility and currency unions on international trade the panel data bilateral observations for five years during 1970 90 covering 186 countries includes 300 observations in which both countries use the same currency i find a large positive effect of a currency union on international trade and a small negative effect of exchange rate volatility even after controlling for a host of features including the endogenous nature of the exchange rate regime these effects statistically significant imply that two countries sharing the same currency trade three times as much as they would with different currencies currency unions like the european emu may thus lead to a large increase in international trade with all that that entails andrew rose

how much nominal rigidity is there in the us economy testing a new keynesian dsge model using indirect inference we evaluate the smets wouters new keynesian model of the us postwar period using indirect inference the bootstrap and a var representation of the data we find that the model is strongly rejected while an alternative new classical version of the model fares no better adding limited nominal rigidity to it produces a weighted model version closest to the data but on data from 1984 onwards the great moderation the best model version is one with a high degree of nominal rigidity close to new keynesian our results are robust to a variety of methodological and numerical issues

housing collateral and the monetary transmission mechanism in this paper we quantify the effects of the recent increase in the housing loan to value ratio ltv on the monetary transmission mechanism we set up a two sector dynamic stochastic general equilibrium model with collateral constraints and production of goods and housing using bayesian methods we quantify the component of the monetary transmission mechanism that is generated by housing collateral we find that this component is substantial and strongly increasing in the ltv we conclude that in order to properly understand the monetary transmission mechanism we need to take into account the effects of housing related collateral constraints and their changing nature

risk constrained self scheduling of a thermal power producer this paper addresses the self scheduling problem of a price taker power producer it focuses on risk modeling emphasizing the tradeoff existing between maximum profit and minimum risk the paper analyzes a self scheduling model that considers simultaneously profit and risk this model is formulated as a mixed integer quadratic programming problem which is solved using commercially available software relevant results from a realistic case study are discussed

the role of energy prices in the great recession a two sector model with unfiltered data we investigate the role of energy shocks during the great recession we study the behaviour of the uk energy and non energy intensive sectors firms in a real business cycle rbc model using unfiltered data the model is econometrically estimated and tested by indirect inference output contraction during the great recession was largely caused by energy price and sector specific productivity shocks all of which are non stationary and hence tend to dominate the sample variance decomposition we also found that the channel by which the energy price shock reduces output in the model is via the terms of trade these fall permanently when world energy prices increase and as substitutes for energy inputs are strictly limited there are few reactions via production channels therefore there is no other way to balance the deteriorating current account than through lower domestic absorption

commitment of electric power generators under stochastic market prices a formulation for the commitment of electric power generators under a deregulated electricity market is proposed the problem is expressed as a stochastic optimization problem in which expected profits are maximized while meeting demand and standard operating constraints under an assumption of perfect competition when an electric power producer has the option of trading electricity at market prices a unit commitment schedule can be obtained by optimizing the self commitment of each unit separately subject to stochastic prices three certainty equivalent formulations of the stochastic self commitment problem are provided the procedures involve application of dynamic programming statistical analysis and asymptotic probability computations the price of electricity is represented by a stochastic model depending on demand generating unit reliabilities and temperature fluctuations we use several approximation methods normal edgeworth series expansion and monte carlo simulation for computing the required probability distributions numerical examples are provided for a market consisting of 150 generating units

house prices borrowing constraints and monetary policy in the business cycle i develop a general equilibrium model with sticky prices credit constraints nominal loans and asset prices changes in asset prices modify agents borrowing capacity through collateral value changes in nominal prices affect real repayments through debt deflation monetary policy shocks move asset and nominal prices in the same direction and are amplified and propagated over time the financial accelerator is not constant across shocks nominal debt stabilises supply shocks making the economy less volatile when the central bank controls the interest rate i discuss the role of equity debt indexation and household and firm leverage in the propagation mechanism finally i find that monetary policy should not target asset prices as a means of reducing output and inflation volatility

how important is the credit channel an empirical study of the us banking crisis we examine whether by adding a credit channel to the standard new keynesian model we can account better for the behaviour of us macroeconomic data up to and including the banking crisis we use the method of indirect inference which evaluates statistically how far a model s simulated behaviour mimics the behaviour of the data we find that the model with credit dominates the standard model by a substantial margin credit shocks are the main contributor to the variation in the output gap during the crisis

the transmission of monetary policy through redistributions and durable purchases this paper studies a redistribution channel for the transmission of monetary policy using a tractable olg setting in which the government is a net debtor we show that standard open market operations omo conducted by central banks have signi cant revaluation eects that alter the level and distribution of wealth in the economy and the real interest rate expansionary omo generate a negative wealth eect the private sector as a whole is a net creditor to the government increasing households incen tives to save for retirement and pushing down the real interest rate this in turn leads to a substitution towards durables generating a temporary boom in the durable good sector with search and matching frictions a form of productive investment is added to the model and the fall in interest rates causes an increase in labour demand raising aggregate employment the mechanism can mimic the empirical responses of key macroeconomic variables to monetary policy interventions the model shows that dierent monetary interventions e g omo versus helicopter drops can have sharply dierent eects on activity

five facts about prices a reevaluation of menu cost models are price decreases 3 the frequency of price increases covaries strongly with inflation whereas the frequency of price decreases and the size of price increases and price decreases do not 4 the frequency of price change is highly seasonal it is highest in the first quarter and then declines 5 we find no evidence of upwardsloping hazard functions of price changes for individual products we show that the first second and third facts are consistent with a benchmark menu cost model whereas the fourth and fifth facts are not

optimization of electricity retailer s contract portfolio subject to risk preferences when an electricity retailer faces volume risk in meeting load and spot price risk in purchasing from the wholesale market conventional risk management optimization methods can be quite inefficient for the management of an electricity contract portfolio in this context we develop a multistage stochastic optimization approach which accounts for the uncertainties of both electricity prices and loads and which permits the specification of conditional value at risk requirements to optimize hedging across intermediate stages in the planning horizons our experimental results based on real data from nordpool suggest that the modeling of price and load correlations is particularly important the sensitivity analysis is extended to characterize the behavior of retailers with different risk attitudes thus we observe that a risk neutral retailer is more susceptible to price related than load related uncertainties in terms of the expected cost of satisfying the load and that a risk averse retailer is especially sensitive to the drivers of the forward risk premium

income and wealth heterogeneity in the macroeconomy how do movements in the distribution of income and wealth affect the macroeconomy we analyze this question using a calibrated version of the stochastic growth model with partially uninsurable idiosyncratic risk and movements in aggregate productivity our main finding is that in the stationary stochastic equilibrium the behavior of the macroeconomic aggregates can be almost perfectly described using only the mean of the wealth distribution this result is robust to substantial changes in both parameter values and model specification our benchmark model whose only difference from the representative agent framework is the existence of uninsurable idiosyncratic risk displays far less cross sectional dispersion and skewness in wealth than u s data however an extension that relies on a small amount of heterogeneity in thrift does succeed in replicating the key features of the wealth data furthermore this extension features aggregate time series that depart significantly from permanent income behavior

institutions in international relations understanding the effects of the gatt and the wto on world trade the general agreement on tariffs and trade gatt and the world trade organization wto have been touted as premier examples of international institutions but few studies have offered empirical proof this article comprehensively evaluates the effects of the gatt wto and other trade agreements since world war ii our analysis is organized around two factors institutional standing and institutional embeddedness we show that many countries had rights and obligations or institutional standing in the gatt wto even though they were not formal members of the agreement we also expand the analysis to include a range of other commercial agreements that were embedded with the gatt wto using data on dyadic trade since 1946 we demonstrate that the gatt wto substantially increased trade for countries with institutional standing and that other embedded agreements had similarly positive effects moreover our evidence suggests that international trade agreements have complemented rather than undercut each other an earlier version of this article was presented at the 99th annual meeting of the american political science association philadelphia august 28 31 2003 we thank tim buthe joanne gowa miles kahler andrew rose arthur stein richard steinberg and seminar participants at stanford university the university of chicago pipes the university of california los angeles the university of california san diego and the university of virginia for many helpful comments we especially thank claire adida ashley conner moonhawk kim erin krampetz james morrison mike nardis natan sachs rachel rubinfeld and jessica weeks for excellent research assistance we are grateful for financial support from the national science foundation career grant ses 0548285 to tomz the stanford center for international development and the vice provost for undergraduate education at stanford

resolving the public sector wage premium puzzle by indirect inference this paper investigates the public sector wage premium pswp in the uk using a microfounded economic model and indirect inference ii to answer the question whether there is public sector wage p

monetary policy and asset prices with belief driven fluctuations abstract we present a heterogeneous agents new keynesian model subject to a cost channel of monetary policy transmission constant turnover between long time traders and newcomers in market activities combined with restricted trading opportunities introduces a feedback from the stock market to real activity making stock prices non redundant for the business cycle we show that strict inflation targeting can lead to equilibrium indeterminacy even if the policy rule satisfies the taylor principle a belief driven shock to stock price generates relative volatilities of key financial variables which are very close to what is observed in u s data this result hints to the possibility that the financial instability witnessed since the mid to late 1990s was the result of waves of rational exuberance and pessimism in financial markets our analysis suggests that a mild response to stock prices in the central bank s policy rule can restore equilibrium determinacy and therefore rule out non fundamental volatility

sticky price models and durable goods the inclusion of a durable goods sector in sticky price models has strong and unexpected implications even if most prices are flexible a small durable goods sector with sticky prices may be sufficient to make aggregate output react to monetary policy as though most prices were sticky in contrast flexibly priced durables with sufficiently long service lives can undo the implications of standard sticky price models in a limiting case flexibly priced durables cause monetary policy to have no effect on aggregate output our analysis suggests that durable goods prices are the most relevant data for calibrating price rigidity jel e21 e23 e31 e52

self commitment of combined cycle units under electricity price uncertainty day ahead energy market clearing relies on a deterministic equivalent model with a limited time horizon which may lead to inefficient scheduling of generating units from the point of view of generators for this reason generators may wish to assume the risk of self committing their units with the hope of securing greater profits this phenomenon may reduce the room for economic signals in the day ahead market in this paper we investigate the influence of risk aversion and price volatility on the decision of generators to self commit units we present a stochastic programming model for self committing combined cycle units under price uncertainty with a conditional value at risk criterion we use benders decomposition to solve the problem and present results on a case study to draw conclusions

offer stack optimization in electricity pool markets we consider a generator making offers of energy into an electricity pool market for a given time period it must submit an offer stack consisting of a fixed number of quantities of energy and prices at which it wants these quantities dispatched we assume that the generator cannot offer enough power to substantially affect the market price so the optimal response would be to offer energy at marginal cost however the market rules do not permit an arbitrary function so the problem is to find an offer stack approximating marginal cost in a way that maximizes its profit we give optimality conditions for this problem and derive an optimization procedure based on dynamic programming this procedure is illustrated by applying it to several examples with different costs of production

a profit based unit commitment ga for the competitive environment as the electrical industry restructures many of the traditional algorithms for controlling generating units need modification or replacement previously utilized to schedule generation units in a manner that minimizes costs while meeting all demand the unit commitment uc algorithm must be updated a uc algorithm that maximizes profit will play an essential role in developing successful bidding strategies for the competitive generator simply bidding to win contracts is insufficient bidding strategies must result in contracts that on average cover the total generation costs no longer guaranteed to be the only electricity supplier a generation company s share of the demand will be more difficult to predict than in the past removing the obligation to serve softens the demand constraint in this paper the authors provide a price profit based uc formulation which considers the softer demand constraint and allocates fixed and transitional costs to the scheduled hours the authors describe a genetic algorithm solution to this new uc problem and present results for an illustrative example

the impact of heat waves on electricity spot markets abstract thermoelectric power plants depend on cooling water drawn from water bodies low river run off and or high water temperatures limit a plant s production capacity this problem may intensify with climate change our study quantifies the impact of forced capacity reductions on market prices production costs consumer and producer surplus as well as emissions by means of a bottom up power generation system model first we simulate the german electricity spot market during the heat wave of 2006 then we conduct a sensitivity study that accounts for future climatic and technological conditions we find an average price increase of 11 during the heat wave 2006 which is even more pronounced during times of peak demand production costs accumulate to an additional but moderate 16 m due to the price increase producers gain from the heat wave whereas consumers disproportionately bear the costs carbon emissions in the german electricity sector increase during the heat wave the price and cost effects are more pronounced and increase significantly if assumptions on heat sensitive demand hydropower capacity net exports and capacity reductions are tightened these are potential additional effects of climate change hence if mitigation fails or is postponed globally the impacts on the current energy system are very likely to rise increases in feed in from renewable resources and demand side management can counter the effects to a considerable degree countries with a shift toward a renewable energy supply can be expected to be much less susceptible to cooling water scarcity than those with a high share of nuclear and coal fired power plants

endogenous money or sticky prices abstract what explains the correlations between nominal and real variables in the postwar us data are these correlations indicative of significant nominal rigidity or do they simply reflect the particular way that monetary policymakers react to developments in the real economy to answer these questions this paper uses maximum likelihood to estimate a model of endogenous money this model allows but does not require nominal prices to be sticky the results show that nominal price rigidity over and above endogenous money plays a role in accounting for key features of the data

a fuzzy optimization approach to dynamic economic dispatch considering uncertainties in this paper the authors propose a fuzzy optimization approach to dynamic economic dispatch considering the uncertainties in deregulated energy and reserve markets the methodology was developed from the viewpoint of a generation company wishing to maximize its own profit and to hedge its risks as a participant in the energy market and 10 min spinning reserve market the uncertainties in the current paper were represented with fuzzy numbers and consist of the demand and reserves required in each market prices cleared in each market and the probability that reserves are called upon in actual operation the energy and reserve markets were coordinated by the generator ramp rate limits the optimal amounts of power and reserve were determined by solving the optimization problem two reserve payment methods payment for power delivered and payment for reserve allocated were investigated in this paper

a stochastic programming model for a day ahead electricity market with real time reserve shortage pricing we present a multi period stochastic mixed integer programming model for power generation scheduling in a day ahead electricity market the model considers various scenarios and integrates the idea of reserve shortage pricing in real time instead of including all the possible scenarios we parsimoniously select a certain number of scenarios to limit the size of the model as realistic size models are still intractable for exact methods we propose a heuristic solution methodology based on scenario rolling that is capable of finding good quality feasible solutions within reasonable computation time

coordination between medium term generation planning and short term operation in electricity markets this paper analyzes the coordination between medium term generation planning and short term operation in electricity markets this coordination is particularly important from a practical point of view in order to guarantee that certain aspects of the operation that arise in the medium term level are explicitly taken into account limited energy resources and obligatory use resources three different approaches are proposed in order to guarantee that short term decisions made by a generation company are consistent with its operation objectives formulated from a medium term perspective these approaches make use of technical and economic signals to coordinate both time scopes primal information dual information and resource valuation functions this paper presents the main advantages and drawbacks of the three approaches and applies them to a case study that uses a conjectural variation based representation of the market

coordinating fuel inventory and electric power generation under uncertainty the authors discuss the problem of hedging between the natural gas and electric power markets based on multiple forecasts for natural gas prices natural gas demand and electricity prices a stochastic optimization model advises a decision maker on when to buy or sell natural gas and when to transform gas into electricity for relatively small models branch and bound solves the problem to optimality larger models are solved using benders decomposition and lagrangian relaxation they apply their approach to the system of an electric utility and succeed in solving problems with 50000 binary variables in less than 4 min to within 1 16 of the optimal value

are labour markets in the new member states sufficiently flexible for emu abstract new member states nms coming from central planning are often advised against early euro adoption because of their rigid labour markets but are labour markets so rigid in these countries we argue in this paper that this is not the case labour market institutions are no more rigid than among current emu members whilst wage bargaining institutions are actually better equipped for microeconomic wage flexibility than in the eu 15 nms also achieved substantial reallocation of jobs and workers in the transition to markets display relatively large job turnover rates and are reducing their regional mismatch the view that nms have rigid labour markets is fuelled by the low job content of growth in the region but there is evidence that the latter is related to productivity enhancing job destruction in the aftermath of prolonged labour hoarding reduced form employment equations estimated in this paper also suggest that tight fiscal policies rather than being harmful to job creation may actually improve the employment performance of the region our interpretation of this result is that loose fiscal policies weaken the confidence of investors and crowd out private employment growth through generous pay rises to civil servants

can public spending boost private consumption this paper analyses the effects on private consumption from an increase in productive and unproductive public spending a new keynesian model incorporating price and wage rigidities monetary policy and various fiscal rules is developed and estimated using bayesian techniques to capture the key cyclical characteristics of the us economy we find that price and wage rigidities along with a positive shock to the part of public spending that is productive are suficient to boost private consumption moreover we show that this initial positive reaction of private consumption is adequate to create a positive present value consumption multiplier for more than five years finally we show that our main results remain robust to changes in the monetary rule and the various methods of deficit financing

priors from general equilibrium models for vars abstract this paper uses a simple new keynesian dynamic stochastic general equilibrium model as a prior for a vector autoregression shows that the resulting model is competitive with standard benchmarks in terms of forecasting and can be used for policy analysis jel classification c11 c32 c53 key words bayesian analysis dsge models forecasting vector autoregressions 1 introduction dynamic stochastic general equilibrium dsge models are popular nowadays in macroeconomics they are taught in virtually every economics ph d program and represent a predominant share of publications in the field yet when it comes to policy making these models are scarcely used at least from a quantitative point of view the main quantitative workhorse for policy making at the federal reserve system is frb us a macro econometric model built in the cowles foundation tradition a style of macroeconomics that is no longer taught in many ph d programs 1 in their decision process fed policy makers rely heavily on forecasting they want to know the expected path of inflation in the next few quarters and by how much a 50 basis point increase in the federal funds rate would affect that path frb us offers answers to these questions answers that many macroeconomists would regard with suspicion given both the lucas 1976 critique and the fact that in general the restrictions imposed by cowles foundation models are at odds with dynamic general equilibrium macroeconomics sims 1980 general equilibrium models on the other hand have a hard time providing alternative answers the fact that these models are perceived to do badly in terms of forecasting as they are scarcely parameterized is perhaps one of the reasons why they are not at the forefront of policy making while progress is being made in the development of dsge models that deliver acceptable forecasts e g smets and wouters 2003 this paper proposes an approach that combines a stylized general equilibrium model with a vector autoregression var to obtain a specification that both forecasts well and is usable for policy analysis specifically the approach involves using prior information coming from a dsge model in the estimation of a vector autoregression loosely speaking this prior can be thought of as the result of the following exercise i simulate time series data from the dsge model ii fit a var to these data in practice we replace the sample moments of the simulated data by population moments computed from the dsge model solution since the dsge model depends on unknown structural parameters we use a hierarchical prior in our analysis by placing a distribution on the dsge model parameters a tightness parameter controls the weight of the dsge model prior relative to the weight of the actual sample markov chain monte carlo methods are used to generate draws from the joint posterior distribution of the var and dsge model parameters the paper shows that the approach makes even a fairly stylized new keynesian dsge model competitive with standard benchmarks in terms of forecasting real output growth inflation and the nominal interest rate the three variables that are of most interest to policy makers 2 up to this point our procedure borrows from the work of dejong ingram and whiteman 1993 and ingram and whiteman 1994 who are the first to use priors from dsge models for vars ingram and whiteman showed that prior information from the bare bones stochastic growth model of king plosser and rebelo 1988 is helpful in forecasting real economic activity such as output consumption investment and hours worked in addition to documenting the forecasting performance of a trivariate var with a prior derived from a monetary dsge model this paper makes two contributions that significantly extend the earlier work first we show formally how posterior inference for the var parameters can be translated into posterior inference for dsge model parameters

on the fit of new keynesian models this article provides new tools for the evaluation of dynamic stochastic general equilibrium dsge models and applies them to a large scale new keynesian model we approximate the dsge model by a vector autoregression and then systematically relax the implied cross equation restrictions and document how the model fit changes we also compare the dsge model s impulse responses to structural shocks with those obtained after relaxing its restrictions we find that the degree of misspecification in this large scale dsge model is no longer so large as to prevent its use in day to day policy analysis yet is not small enough to be ignored

liquidity constraints and intertemporal consumer optimization theory and evidence from durable goods this paper develops and tests the implications of optimal consumption behavior with borrowing constraints the theory shows that liquidity constraints imply a distinctive intertemporal relationship between durable and nondurable goods consumption binding liquidity constraints appear as part of an error correction term derived from the long run cointegrating relationship between durables and nondurables when liquidity constraints are binding the error correction term will have predictive power for the future change in nondurable consumption empirical tests of the implications using aggregate data support the hypothesis that liquidity constraints rather than rule of thumb behavior best explain the excess sensitivity of consumption to predictable changes in income copyright 1995 by ohio state university press

how important are the international financial market imperfections for the foreign exchange rate dynamics a study of the sterling exchange rate the uk has been a net debtor over the past two decades and the sterling exchange rates are sensitive to any chaos that might occur in the financial market this paper examines the importance of the international financial imperfections in the sterling exchange rate dynamics we build a small open economy dsge model with the constrained international financial institutions that intermediate capital flows and derive tractable analytical solutions the constraint works to introduce a wedge between lending and borrowing rates which compensates financiers for their currency risk taking the model has been estimated by using a simulation based indirect inference approach which provides a natural framework for testing the hypothesis implied by the model we find that the model cannot be rejected by the uk data shocks to financial forces are the main driving forces behind the large and sudden depreciation of the sterling exchange rates in the aftermath of the collapse of lehman brothers and the brexit vote furthermore the optimal policy rules have been proposed

stabilisation policy rational expectations and price level versus inflation targeting a survey we survey literature comparing inflation targeting it and price level targeting pt as macroeconomic stabilisation policies our focus is on new keynesian models and areas that have seen significant developments since ambler s 2009 price level targeting and stabilisation policy a survey journal of economic surveys 23 5 974 997 survey optimal monetary policy the zero lower bound financial frictions and transition costs of adopting a pt regime ambler s conclusion that pt improves social welfare in new keynesian models is fairly robust but we note an interesting split in the literature pt consistently outperforms it in models where policymakers commit to simple taylor type rules but results in favour of pt when policymakers minimise loss functions are overturned with small deviations from the baseline model since the beneficial effects of pt appear to hang on the joint assumption that agents are rational and the economy new keynesian we discuss survey and experimental evidence on rational expectations and the applied macro literature on the empirical performance of new keynesian models overall the evidence is not clear cut but we note that new keynesian models can pass formal statistical tests against macro data and that models with rational expectations outperform those with behavioural expectations i e heuristics in direct statistical tests we therefore argue that policymakers should continue to pay attention to pt

risk constrained bidding strategy with stochastic unit commitment this paper develops optimal bidding strategies based on hourly unit commitment in a generation company genco that participates in energy and ancillary services markets the price based unit commitment problem with uncertain market prices is modeled as a stochastic mixed integer linear program the market price uncertainty is modeled using the scenario approach monte carlo simulation is applied to generate scenarios scenario reduction techniques are applied to reduce the size of the stochastic price based unit commitment problem and postprocessing is applied based on marginal cost of committed units to refine bidding curves the financial risk associated with market price uncertainty is modeled using expected downside risk which is incorporated explicitly as a constraint in the problem accordingly the proposed method provides a closed loop solution to devising specific strategies for risk based bidding in a genco illustrative examples show the impact of market price uncertainty on genco s hourly commitment schedule and discuss the way gencos could decrease financial risks by managing expected payoffs

the efficient estimation of econometric models with rational expectations the efficient estimation of econometric models with rational expectations by the substitution method usually entails the use of a non linear simultaneous equations estimator and hence is not very attractive computationally it is shown that for a wide class of problems efficient estimates can also be obtained with standard estimation methods if instead an errors in variables approach is used for many other problems although not providing fully efficient estimates because rationality is not imposed the errors in variables method will still have a strong appeal because otherwise it uses all of the structural information in the model unlike the substitution method when an incomplete information set is used it guarantees consistent estimates and it is easy to compute

consumption and capital market imperfections an international comparison the excess sensitivity of consumption to current income fluctuations is higher in countries where consumers borrow less low levels of consumer debt can result either from capital market imperfections or from a low demand for loans the evidence suggests that the former view is more appropriate than the latter and thus supports the hypothesis that excess sensitivity may be attributed to liquidity constraints rather than to other factors copyright 1989 by american economic association

multimarket optimal bidding for a power producer this paper considers a profit maximizing thermal producer that participates in a sequence of spot markets namely day ahead automatic generation control agc and balancing markets the producer behaves as a price taker in both the day ahead market and the agc market but as a potential price maker in the volatile balancing market the paper provides a stochastic programming methodology to determine the optimal bidding strategies for the day ahead market uncertainty sources include prices for the day ahead and agc markets and balancing market linear price variations with the production of the thermal producer results from a realistic case study are reported and analyzed conclusions are duly drawn