a new decision rule for lateral transshipments in inventory systems this paper deals with a single echelon inventory system consisting of a number of parallel local warehouses facing compound poisson demand there are standard holding and backorder costs as well as ordering costs at all warehouses normally the warehouses replenish from an outside supplier however lateral transshipments between the warehouses are also possible such transshipments take no time but incur additional costs when a demand occurs at a warehouse the question is whether the whole demand or part of it should be covered by a lateral transshipment from another warehouse given a set of alternative decisions our decision rule minimizes the expected costs under the assumption that no further transshipments will take place this rule is then used repeatedly as a heuristic a simulation study illustrates how the suggested technique performs under different conditions

optimal policies for a capacitated two echelon inventory system this paper demonstrates optimal policies for capacitated serial multiechelon production inventory systems extending the clark and scarf 1960 model to include installations with production capacity limits we demonstrate that a modified echelon base stock policy is optimal in a two stage system when there is a smaller capacity at the downstream facility this is shown by decomposing the dynamic programming value function into value functions dependent upon individual echelon stock variables we show that the optimal structure holds for both stationary and nonstationary stochastic customer demand finite horizon and infinite horizon results are included under discounted cost and average cost criteria

money income prices and interest rates including data from the 1980s sharply weakens the postwar time series evidence indicating significant relationships between money however defined and nominal income or between money and either real income or prices separately focusing on data from 1970 onward destroys this evidence altogether evidence indicating cointegration of real income and real money balances with due allowance for the effect of interest rates also deteriorates when the sample extends through the 1980s a positive finding is that the spread between the commercial paper rate and the treasury bill rate consistently contains highly significant information about future movements in real income copyright 1992 by american economic association

a periodic review production planning model with uncertain capacity and uncertain demand optimality of extended myopic policies increasing product complexity manufacturing environment complexity and an increased emphasis on product quality are all factors leading to uncertainties in production processes these uncertainties are in the form of unplanned machine maintenance varying production yields and rework among others in planning for production an adequate model must incorporate these uncertainties into the representation of the production process this paper treats the aggregate planning problem for a single product with random demand and random capacity in the single period problem random capacity does not affect the optimal policy but results in a unimodal nonconvex cost function in the multiple period and infinite horizon settings order up to policies that are dependent on the distribution of capacity are shown to be optimal in spite of a nonconvex cost in the infinite horizon setting an intuitive description of the situation leads to the notion of a class of extended myopic policies requiring the consideration o

the structure of periodic review policies in the presence of random yield this work provides a comprehensive analysis of a general periodic review production inventory model with random variable yield existence of an order point whose value does not depend on yield being random is proved in the single period case without specifying the yield model and using a very general cost structure when yield is a random multiple of lot size the nonorder up to optimal policy is characterized for a finite horizon model the finite horizon value functions are shown to converge to the solution of an infinite horizon functional equation and the infinite horizon order point is shown to be no smaller than when yield is certain

structural changes and the us money demand function previous literature on the stability of the us money demand function suggests mixed results in this article we study the stability of the money demand function from the standpoint of structural changes in the function we first investigate if a stable money demand function can be found for the us for the period from the first quarter of 1959 to the fourth quarter of 2000 the results show that a stable long run money demand function does not exist for the sample period under consideration we then estimate unknown structural break points in the variables of the money demand function using bai and perron s 1998 method and test if there is a stable relationship in each sub sample period of the break points the results show that a stable relationship exists for each sub sample period the estimated income elasticity and interest rate semi elasticity are relatively smaller than ball s 2001 estimates but consistent with his argument

existence of coordinating transshipment prices in a two location inventory model we consider a two location production inventory model where each location makes production decisions and is subject to uncertain capacity each location optimizes its own profits transshipment at a cost is allowed from one location to another we focus on the question of whether one can globally set a pair of coordinating transshipment prices i e payments that each party has to make to the other for the transshipped goods that induce the local decision makers to make inventory and transshipment decisions that are globally optimal a recent paper suggests for a special case of our model that there always exists a unique pair of coordinating transshipment prices we demonstrate through a counterexample that this statement is not correct and derive sufficient and necessary conditions under which it would hold we show that in some conditions coordinating prices may exist for only a narrow range of problem parameters and explore conditions when this can happen finally we study the effects of demand and capacity variability on the magnitude of coordinating transshipment prices

optimal production and inventory policy for multiple products under resource constraints we show that a modified base stock policy is optimal for multiproduct infinite horizon production inventory systems where demand for the products is random and the products share a finite resource every period we characterize the optimal policy for the case of homogeneous products because of the difficulty in computing the optimal base stock levels for the heterogeneous case we propose a heuristic that is simple enough for practical applications we present numerical results that suggest that the heuristic yields near optimal solutions

another look at long run money demand abstract this paper investigates the long run demand for m1 in the postwar united states previous studies based on data ending in the late 1980s are inconclusive about the parameters of postwar money demand this paper obtains precise estimates of these parameters by extending the data through 1996 the income elasticity of money demand is approximately 0 5 and the interest semi elasticity is approximately 0 05 these parameters are significantly smaller in absolute value than the corresponding parameters for the prewar period a caveat is that the analysis assumes there is no trend in money demand resulting from technological change

a three stage model for a decentralized distribution system of retailers we present and study a three stage model of a decentralized distribution system consisting ofn retailers each of whom faces a stochastic demand for an identical product in the first stage before the demand is realized each retailer independently orders her initial inventory in the second stage after the demand is realized each retailer decides how much of her residual supply demand she wants to share with the other retailers in the third stage residual inventories are transshipped to meet residual demands and an additional profit is allocated our model is an extension of the two stage model of anupindi et al abz 2001 which implicitly assumes that all residuals enter the transshipment stage we show however that allocation rules in the third stage based on dual solutions which were used in the abz model may induce the retailers to hold back some of their residual supply demand in general we study the effect of implementing various allocations rules in the third stage on the values of the residual supply demand the retailers are willing to share with others in the second stage and the trade off involved in achieving an optimal solution for the corresponding centralized system

stability of the money demand function in asian developing countries previous studies that estimated the money demand function in asian developing countries either employed traditional estimation techniques or recently popularized cointegration technique while the first group suffers from spurious regression problems the second group interpreted their finding of cointegration as a sign of stability of estimated parameters this study after incorporating the cusum and cusumsq tests into cointegration analysis shows that in some asian countries even though real m1 or m2 monetary aggregates are cointegrated with their determinants the estimated parameters are unstable

optimal joint replenishment and transshipment policies in a multi period inventory system with lost sales mismatch between supply and demand when the uncertainty of the demand is high and the supply lead time is relatively long such as seasonal good markets can result in high overstocking and understocking costs in this paper we propose transshipment as a powerful mechanism to mitigate the mismatch between the supply and demand we consider a finite horizon multi period inventory system where in each period two retailers have the option to replenish their inventory from a supplier if there is any supply or via transshipment from the other retailer each retailer observes nonnegative stochastic demand with general distribution in each period and incurs overstocking understocking costs as well as costs for replenishment and transshipment that may be time dependent we study a stochastic control problem where the objective is to determine the optimal joint replenishment and transshipment policies so as to minimize the total expected cost over the season we characterize the structure of the optimal policy a

joint inventory and markdown management for perishable goods with strategic consumer behavior in this paper we formulate and analyze a novel model on a firm s dynamic inventory and markdown decisions for perishable goods we consider a dynamic stochastic setting where every period consists of two phases clearance phase and regular sales phase in the clearance phase the firm decides how much to order for regular sales as well as whether to markdown some or all of the leftover inventory from the previous period that will be disposed otherwise since strategic consumers may buy the product during clearance sales for future consumption markdown may cannibalize future sales at regular price hence the firm needs to make a trade off between product spoilage and intertemporal demand substitution we show that the firm should either put all of the leftover inventory on discount or dispose all of it and the choice depends on the amount of leftover inventory from the previous period in particular the firm should introduce markdown when the amount of leftover inventory is higher than a certain th

the demand for m1 in the u s a 1960 1988 estimated u s m1 demand functions appear unstable regularly breaking down over 1960 1988 e g missing money great velocity decline m1 explosion we propose a money demand function whose arguments include inflation real income long term bond yield and risk t bill interest rates and learning curve weighted yields on newly introduced instruments in m1 and non transactions m2 the model is estimated in dynamic error correction form it is constant and with an equation standard error of 0 4 variance dominates most previous models estimating alternative specifications explains earlier breakdowns showing the model s distinctive features to be important in accounting for the data

a capacitated production inventory model with periodic demand for a single product single stage capacitated production inventory model with stochastic periodic cyclic demand we find the optimal policy and characterize some of its properties we study the finite horizon the discounted infinite horizon and the infinite horizon average cases a simulation based optimization method is provided to compute the optimal parameters based on a numerical study several insights into the model are also provided

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

cointegration and structural change an application to the u s demand for money wankeun oh i perform the cointegration tests for the trivariate model of real monetary aggregates real personal income and short term interest rate i find the existence of a long run relationship among these three variables to check the stability of a long run money demand relationship i implement a rank constancy test and cusum test the test results show that real mi is relatively more stable than other aggregates but structural change occurred during the 1970s and early 1980s this is consistent with prior research on money demand jel e41 i introduction incorporating structural change when performing tests on the properties of stochastic processes is important because structural breaks may cause misspecification problems most tests of structural change consider the stability of the parameters over time tests for structural breaks and parameter stability have been studied extensively a partial list includes chow 1966 brown et al 1975 harvey and collier 1977 king 1987 ploberger et al 1989 in the context of unit root processes perron 1989 showed that the presence of a one time change in the level or slope of the trend function can severely distort the results of unit root tests and it is natural to ask how structural change can distort the results of cointegration tests 1 traditional tests of parameter stability ask if the parameters of the model are constant in contrast quintos 1993 proposed a test for stability of the long run relationship s in a cointegrating regression the test is based on johansen s 1988 framework and the test statistic is simply the weighted sum of the likelihood ratio test as given in johansen 1988 quintos s rank test is very different from the traditional cusum and chow tests for parameter stability because her rank test checks for stability of the cointegrating relationship between variables in other words the rank test checks whether cointegration holds for the full period the traditional cusum and chow tests assume that cointegration holds for the full period or does not hold for the full period and tests simply whether the cointegration vector changes for example if there is cointegration from 1960 1990 between revenues and expenditures with cointegrating vector 1 1 then the cusum and chow tests check whether the cointegra ting vector 1 1 is stable throughout the period the rank constancy test checks whether the cointegration rank is stable throughout the period not whether the cointegrating vector is stable at 1 1 in other words the rank test will check whether for example there is cointegration from 1960 1980 and no cointegration from 1980 onward the chow and cusum tests are not designed to check for this the structural stability of money demand relationships has been the issue of a substantial number of empirical studies 2 in general structural stability means stability of the underlying behavioral equations 3 this term includes parameter stability and stability of functional form friedman s 1990 research on the money demand function assumes that a long run equilibrium relationship exists between real money balances real income or real wealth and the opportunity cost of holding real money balances recently there has been strong evidence of cointegration between real income real money balances and a nominal interest rate for instance engle and granger 1987 dickey et al 1991 hafer and jansen 1991 hoffman and rasche 1991 mehra 1993 miller 1991 fischer and nicoletti 1993 and baba et al 1992 report on cointegration among variables in u s aggregate money demand jain and moon 1994 report on cointegration in u s sectoral money demand yashiv 1994 and engsted 1993 on money demand in a high inflation country and hoffman et al 1995 report on international money demand comparison this article asks if long run money demand relationship is stable and if so for which measure of money is it stable over time

australasian money demand stability application of structural break tests estimates of the demand for money provide important foundations for monetary policy setting but if the estimation technique does not explicitly account for structural changes then such estimates will be biased this paper presents an investigation into the level and stability of money demand m1 for australia and new zealand over the 1960 2009 period and demonstrates that both countries experienced regime shifts australia also experienced an intercept shift application of four time series methods provide consistent results with 1984 and 1998 break dates cusum and cusumsq stability tests reveal that m1 demand functions were unstable over the 1984 to 1998 period for both countries although tests for stability are not rejected thereafter

long run income and interest elasticities of money demand in the united states econometric techniques designed to accommodate nonstationary data are used to reexamine the stability of interest and income elasticities of money demand in the united states estimates based on postwar monthly data reveal a stable relationship between m1 velocity and various measures of interest rates that proxy the opportunity cost of holding money balances tests for the existence of cointegration and methods used to estimate the income and interest elasticities are based on procedures prescribed by soren johansen 1988 corresponding error correction estimates offer insight as to the dynamics of the process that maintains the equilibrium relation between velocity and interest rates copyright 1991 by mit press

optimal joint inventory and transshipment control under uncertain capacity in this paper we address the optimal joint control of inventory and transshipment for a firm that produces in two locations and faces capacity uncertainty capacity uncertainty e g due to downtime quality problems yield etc is a common feature of many production systems but its effects have not been explored in the context of a firm that has multiple production facilities we first characterize the optimal production and transshipment policies and show that uncertain capacity leads the firm to ration the inventory that is available for transshipment to the other location and characterize the structure of this rationing policy then we characterize the optimal production policies at both locations which are defined by state dependent produce up to thresholds we also describe sensitivity of the optimal production and transshipment policies to problem parameters and in particular explain how uncertain capacity can lead to counterintuitive behavior such as produce up to limits decreasing for locations that face stochastically higher demand we finally explore through a numerical study when the optimal policy is most likely to yield significant benefits compared to simple policies

economic policies and demand for money evidence from canada this study identifies canadian fiscal and monetary policy regime changes that could influence the services of money it is argued that if these policy regime changes were not incorporated in the estimation of demand for real balances the resulting estimate would be biased and unstable using canadian monthly data for the january 1975 to june 2001 period the paper estimates a standard demand for money m1 function with and without these policy regime changes it was found the demand for money in canada is stable over the short and long run periods when these policy regime changes are incorporated and the estimated coefficients have correct signs

the reincarnation of keynesian economics this paper discusses the reemergence of keynesian economics during the past decade it highlights the substantial differences between new keynesian economics and the convictions of early keynesians in particular it points out that new keynesians have adopted many views that were once considered monetarist or classical it concludes that the term keynesian may have outlived its usefulness this abstract was borrowed from another version of this item this abstract was borrowed from another version of this item

short run money demand abstract the conventional wisdom holds that the short run demand for money is unstable this paper challenges the conventional view by finding a stable demand for m1 in u s data from 1959 through 1993 the approach follows previous work in interpreting long run money demand as a cointegrating relation and it uses goldfeld s partial adjustment model to interpret short run dynamics the key innovation is the choice of the interest rate in the money demand function most previous work uses a short term market rate but this paper uses the average return on near monies the savings accounts and money market mutual funds that are close substitutes for m1 this choice helps rationalize the behavior of money demand in particular the increase in the volatility of velocity after 1980 is explained by increased volatility in the returns on near monies

the case for a financial approach to money demand the distribution of money across households is much more similar to the distribution of financial assets than to that of consumption levels even controlling for life cycle effects this is a puzzle for theories which directly link money demand to consumption such as cash in advance cia money in the utility function miuf or shopping time models this paper shows that the joint distribution of money and nancial assets can be explained by an incomplete market model when frictions are introduced into financial markets money demand is modeled as a portfolio choice with a fixed transaction cost in financial markets

an efficient and incentive compatible dynamic auction for multiple complements this article proposes an efficient and incentive compatible dynamic auction for selling multiple complementary goods the seller has reserve prices the auctioneer announces a current price for every bundle of goods and a supply set of goods every bidder responds with a set of goods demanded at these prices and the auctioneer adjusts prices we prove that even when bidders can exercise their market power strategically this dynamic auction always induces them to bid truthfully resulting in an efficient allocation its supporting walrasian equilibrium price for every bundle of goods and a generalized vickrey clarke groves payment for every bidder

time varying parameter error correction models the demand for money in venezuela 1983 i 1994 iv the possibility of using time varying parameter models in the context of error correction models is studied empirically as an application a money demand relationship m1 for venezuela is estimated from 1983 to 1994 within a cointegrated var framework first the stochastic properties of the series are analysed studying each corresponding order of integration second the existence of a long run stable relation between the variables involved has been investigated and then the cointegration relation and the short run adjustment mechanism estimated as both relations are identified in the context of constant parameters a stability analysis is performed finally the technique of kalman filtering is used to estimate a model that permits the short run parameters to vary while the parameters of the long run relation are kept constant

a theory based state dependent phillips curve and its estimation to explain the existing empirical irregularity about the slope of a phillips curve this article provides a model of imperfect competition to short that the slope of a phillips curve is shock dependent we empirically apply a state space markov switching model to examine the impact of inflation surprise on the unemployment gap resulting in the state dependent phillips curve fitting quite well our empirical evidence indicates that an unexpected monetary expansion does produce effects in reducing unemployment rates and that supply shocks should not be ignored in estimating the phillips curve because they dominate demand shocks in several nonoil shock periods jel c51 e24 e52 i introduction it is well known that a downward sloping short run phillips curve implies a trade off between the inflation rate and unemployment rate however empirical findings point out that the slope of the phillips curve depends on the selected sample periods 1 does any theoretical model explain the changes in the slope of a short run phillips curve as displayed in the data can we find empirical support for our model that implies a slope changeable phillips curve to answer these questions this article provides a theoretical model implying that the slope of the phillips curve is shock dependent we then apply a state space markov switching model to investigate the empirical support of the theoretical model although a stable negative short run phillips curve is crucial for producing inflation forecasts in policy making institutions there is no general consensus about the negative slope of the phillips curve in empirical literature 2 one of the explanations to the previous empirical irregularity as suggested by king and watson 1994 is that the relationship between unemployment and inflation is shock dependent which means that the slope of a phillips curve relies on the dominance of the demand or supply shocks therefore the conventional single equation regression based on the state independent framework is not appropriate apart from neglecting the state dependent characteristic of the phillips curve there are several other drawbacks for conventional empirical studies when investigating the phillips curve first many articles assume that forecast errors of inflation are homoscedastic which is challenged in the literature the homoscedastic assumption is debatable because several studies such as engle 1983 jansen 1989 evans 1991 and brunner and hess 1993 point out significant heteroscedasticity in the u s inflation rate arch or garch type models provide estimates of how the conditional variance of inflation varies over time within a given structure and therefore they ignore the possibility of structural changes caused by changing regimes a markov switching heteroscedasticity model is an alternative that allows regime changes in the variance structure instead of applying arch type models to estimate the time varying conditional variance of inflation within a given structure this article takes into account the influence of regime changes on inflation s variance we apply the state dependent conditional heteroscedasticity approach provided by brunner and hess 1993 and evans and wachtel 1993 to estimate the forecasting errors of inflation the second drawback is a constant natural rate assumption the unemployment gap is the difference between the unemployment rate and the natural rate conventional literature assumes a constant natural rate which is challenged theoretically and empirically as stated by gordon 1997 the existence of unionization unemployment insurance programs and labor force demographics leads to a highly persistent unemployment rate we therefore assume that the unobservable natural rate is time varying and behaves in accordance with the hysteresis of unemployment rates 3 recent empirical works of a regime switching approach on the phillips curve have focused on whether the relationship between inflation and unemployment rates is nonlinear as in ferri et al

stochastic trends and economic fluctuations in a large open economy abstract this study examines the role of stochastic trends in real exchange rates and foreign output in explaining economic fluctuations in the united states while many of the results are consistent with recent closed economy studies the evidence shows that external shocks have significant short run effects on economic fluctuations even in a large country a real appreciation of the dollar leads to permanent decreases in net exports and temporary decreases in output permanent shocks to real exchange rates have surprisingly large effects on output over the course of the normal business cycle

nonlinear equilibrium correction in u s real money balances 1869 1997 several theoretical models of money demand imply nonlinear functional forms for the aggregate demand for money characterized by smooth adjustment toward long run equilibrium in this paper we propose a nonlinear equilibrium correction model of u s money demand that is shown to be stable over the sample period from 1869 to 1997

sweep programs the fall of m1 and rebirth of the medium of exchange this paper investigates the effect of sweep programs on m1 using dynamic simulations of money demand over 1994 2000 the postsample period constitutes when sweep programs have been in effect all models generate predictions systematically above reported m1 using data on newly initiated programs test findings indicate that sweeps account for the overprediction within the conventional money demand model with a long term interest rate we construct a medium of exchange measure m1s equal to m1 plus estimated holdings of sweep balances m1s velocity compares favorably with that of broader aggregates evidence indicates cointegration within m1s money demand

the demand for broad money in the uk does credit matter empirical work based on portfolio theories of the demand for money traditionally treat the quantity of money demanded as the outcome of a decision to allocate a fixed amount of wealth by contrast this paper argues that people commonly hold money at the same time that they borrow thus changes in gross wealth will cause changes in the quantity of money people wish to hold this suggests that empirical work in the demand for broad money should pay attention to the cost of credit we estimate the demand for broad money in the uk 1969q1 1994q4 using the recently developed time series techniques of dols and fpls our findings show that the cost of credit variables are important determinants of the demand for real m4 in the uk in contrast to the recent empirical literature our results provide strong evidence for the hypothesis that interest rates have a short and long term causal impact on real money demand in the uk

the stability of long run money demand in five industrial countries abstract this study provides strong evidence for the stability of long run demand functions for narrowly defined money m1 in five industrial countries u s japan canada u k and west germany using post war quarterly data evidence of stability is examined using two different estimation techniques and through a formal test of parameter constancy designed specifically for cointegrating vectors in the majority of these countries the key to stability is the imposition of a unitary long run income elasticity that is rarely rejected by the data

a money demand function with output uncertainty monetary uncertainty and financial innovations in a general equilibrium framework incorporating the money in the utility function approach we show that output uncertainty and monetary uncertainty as well as output interest rates and financial innovations affect money demand the estimated long run relationships are consistent with our postulated relation but not with the conventional one our model delivers a high income elasticity consistent with cross sectional evidence and helps resolve m1 demand puzzles the model estimated in dynamic error correction form exhibits a good level of stability and forecastability providing little support for the recent de emphasis of monetary aggregates due to the instability of money demand

monetary shocks in the g 6 countries is there a puzzle les auteurs cherchent a clarifier la dynamique du mecanisme de transmission de la politique monetaire l identification des chocs de politique monetaire est au coeur de ce genre d analyse divers chercheurs ont reussi recemment a isoler de tels chocs en imposant des restrictions de suridentification a des modeles vectoriels autoregressifs var

u s narrow money for the twenty first century i introduction though money retains its fundamental role in a market economy money measures have been noticeably de emphasized within the conduct of u s monetary policy the federal open market committee fomc stopped reporting annual growth objectives for monetary aggregates although it states that money supply still has value for gauging economic conditions board of governors 2000 however a growing body of research calls for returning monetary aggregates to a more prominent role within monetary policy meltzer 1998 asserts that the view of persistent money growth as being the source of inflation is again widely accepted perhaps more firmly held by some central bank governors now than at any time in the twentieth century nelson 2002 provides evidence that base money has a significant effect on output relative to potential in the united states and united kingdom even after controlling for the short term real interest rate nelson 2003 argues that money growth governs the mean and dynamics of inflation in present day new keynesian models leeper and roush 2003 find evidence of an essential role for m2 within the transmission of monetary policy even after controlling for the nominal interest rate 1 this article focuses on the role of sweep programs in properly measuring narrow money in a sweep program banks move a portion of funds from customer demand deposits dds or other checkable deposits ocds into instruments with zero statutory reserve requirements we examine the effects of two types of sweep programs in the united states retail sweep programs and commercial demand deposit sweep programs narrow transactions based money historically has played a key role in the conduct of monetary policy as hafer and wheelock 2001 explain m1 served as the measure of money within the st louis model although monetarists had long been divided over whether a narrow or broad aggregate was the preferable target for monetary policy the fomc appeared to focus on m1 during the 1970s and early 1980s publishing their target ranges for money growth in terms of m1 hafer and wheelock 2001 though state that deviations in m1 velocity from its upward trend beginning in the early 1980s caused instability within the st louis model hoffman and rasche 1991 and hoffman et al 1995 place dummy variables in their vector error correction mechanisms to capture observed shifts in m1 velocity what attention remains on the money supply seems to be focused on broad rather than narrow aggregates but the broad aggregates have not escaped difficulties duca 2000 and hafer and wheelock 2001 document a deviation of m2 velocity from its long run trend in the early 1990s sometimes characterized as the missing m2 episode duca and vanhoose 2004 state that one response was to replace m2 with mzm consistent with the view that heightened substitution between small time deposits and mutual funds other than money market mutual funds mmmfs largely accounted for the instability in m2 velocity but as they go on to discuss m2 and mzm velocity encountered problems in the early 2000s plunging in ways not in line with opportunity cost variables duca and van hoose 2004 state that broader aggregates may have become more vulnerable to portfolio substitution involving stock and mutual funds other than mmmf narrow money has also been used extensively in examining money demand a sizable body of research has emerged that empirically investigates the demand for m1 especially using cointegration techniques hoffman and rasche 1991 hoffman et al 1995 dutkowsky and atesoglu 2001 and ball 2001 provide evidence of a stable long run money demand equation using m1 ball 2002 generates further support with m1 and establishes a correspondence between the partial adjustment formulation and the vector error correction model yet research and policy making using narrow money is currently being hampered by the lack of an accurate measure of transactions based money

optimal and approximate policies in multiperiod multilocation inventory models with transshipments this paper examines the effects on the optimal ordering policy and its cost of allowing for interactions among retail outlets specifically transshipments are allowed as recourse actions occurring after demands are realized but before they must be satisfied the resultant savings in holding and shortage costs are balanced against the costs of transshipment a base stock ordering policy is optimal for this model if the final period base stock order up to point is nonnegative then it will be the base stock order up to point for all periods unfortunately it can be found analytically only for two special cases where either the cost parameters are equal at every outlet or there are only two outlets these two special cases are used to validate a heuristic solution technique employing monte carlo integration which is then compared to an easily calculated base policy in order to gauge the contribution of this model the additional savings from using this heuristic policy are significant particularly for problems with many retail outlets and low transshipment costs

inventory sharing and rationing in decentralized dealer networks an increasing number of manufacturers have started to pursue a strategy that promotes inventory sharing among the dealers in their distribution network in this paper we analyze a decentralized dealer network in which each independent dealer is given the flexibility to share his inventory we model inventory sharing as a multiple demand classes problem in which each dealer faces his own customer demand with high priority and inventory sharing requests from other dealers with low priority assuming that each dealer uses a base stock and threshold rationing policy for his inventory stocking and inventory sharing decisions we explicitly model the interactions between the dealers through inventory sharing and obtain aclosed form cost function for each dealer based on the steady state distribution of the inventory levels at the two dealers we then provide a detailed supermodularity analysis of the inventory sharing and inventory rationing game in which each dealer has a two dimensional strategy set stocking level and rationing level we show that the full sharing game in which dealers precommit to sharing all of their on hand inventory and the fixed sharing level game in which dealers precommit to sharing a portion of their on hand inventory are supermodular and thus a pure strategy nash equilibrium is guaranteed to exist for the rationing game in which dealers precommit to their stocking levels we show that there exists a dominant strategy equilibrium on the dealers sharing rationing levels finally a comprehensive computational study is conducted to highlight the impact of the manufacturer s incentives subsidies and or transshipment fees on the dealers sharing behavior

lessons on monetary policy from the 1980s t he half decade running from mid 1982 to mid 1987 was a pretty good era for u s monetary policy as these things go a sharp easing of policy beginning some time around midyear 1982 helped set in motion a recovery from the most severe business downturn the united states had experienced since the 1930s a downturn that tight monetary policy earlier on had deliberately brought about in order to slow the alarming acceleration of prices the recovery that ensued developed into a sustained expansion that continued without interruption through the end of 1987 thereby setting a new record for the longest recorded business expansion in u s peacetime experience a fiscal policy based on unprecedentedly large and continually growing structural budget deficits was a major factor underlying this record length expansion but at least monetary policy did not stand in the way just as importantly the severe 1981 82 recession served its intended purpose of substantially restoring price stability and even after five years of expansion inflation remained modest by recent historical standards at least as judged by these outcomes for the standard objectives of macroeconomic policy u s monetary policy was a distinct success during these years economists hoping to say something useful about monetary policy have had a tougher time the quantitative relationships connecting income and price movements to the growth of familiar monetary aggregates including especially the m1 measure of the money stock that had been the chief focus of monetary policy during 1979 82 utterly fell apart during this period moreover the collapse of these long standing

production and inventory control for a make to stock calibrate to order system with dedicated and shared resources consider a firm that produces multiple products on dedicated production lines stage 1 which are further customized calibrated on a shared resource stage 2 common to all products the dedicated production lines and the shared resource for calibration face capacity uncertainties the firm holds inventory of products that are not yet calibrated and carries out calibration when an order is received we analyze a multiperiod inventory model for two products and derive the optimal production policy at stage 1 as well as the optimal allocation of the shared resource to demands at stage 2 for the shared resource because of its capacity uncertainty not only the total planned production quantities matter but also the sequence in which the products are processed we characterize the optimal allocation of the shared resource and show that the optimal policy keeps the ending inventories of products as close to a so called target path as possible for the dedicated production lines because of their capacit

an evaluation of friedman s monetary instability hypothesis in this article i examine what i call milton friedman s monetary instability hypothesis drawing on friedman s work i argue that there are two main components to this view the first component is the idea that deviations between the public s demand for money and the supply of money are an important source of economic fluctuations the second component of this view is that these deviations are primarily caused by fluctuations in the supply of money rather than the demand for money each of these components can be tested independently to do so i estimate an otherwise standard new keynesian model amended to include a money demand function consistent with friedman s work and a money growth rule for a period from 1875 to 1963 this structural model allows me to separately identify shocks to the money supply and shocks to money demand i then use variance decompositions to assess the relative importance of shocks to the supply and demand for money i find that shocks to the monetary base can account for up to 28 of the fluctuations in output whereas money demand shocks can account for less than 1 of such fluctuations this provides support for friedman s view

nonstationary stochastic seasonality and the german m2 money demand function abstract in this paper nonstationary stochastic seasonality is investigated to model the german m2 money demand function using quarterly data for the period from 1960 to 1996 empirical evidence is found in favour of a stable long run m2 money demand function relying on seasonally unadjusted data while it is not possible to establish a stable long run relationship using seasonally adjusted times series the seasonal error correction model exhibits satisfactory properties and fits the data quite well however it shows parameter nonconstancy especially in the middle of the 1970s and at the beginning of the 1990 s when major monetary regime changes took place

the time varying performance of the long run demand for money in the united states george s tavlas this article investigates the issues of the stability and predictability and interestsensitivity of money demand over 1870 1997 two different estimation methodologies are used random coefficient rc modeling and vector error correction vec modeling the former procedure allows the profiles of the coefficients to be traced over time and relaxes several restrictions routinely imposed in applied work the results indicate that different estimation methodologies using different data periods and frequencies yield estimates of some of the coefficients of the long run demand for money that fall within a fairly narrow range the results also suggest that specification errors have had an important influence on the time profile of the interest elasticity of money demand and that there is a tendency for the interest elasticity to decline in absolute value as interest rates decline jel c20 e47 i introduction this article reinvestigates the issues of the stability predictability and interestsensitivity of the long run demand for money in the united states 1 the model used is closely based on that used by friedman and schwartz 1982 the data are also those of friedman and schwartz extended by bordo et al 1997 and us to include more recent observations while the data frequency is annual rather than averaged over business cycle phases as used by friedman and schwartz 2 two very different methodologies are used to examine the issue of money demand behavior vector error correction vec modeling and random coefficient rc modeling the former approach is aimed at addressing problems of spurious correlation produced by integrated variables and dynamic misspecification due to inadequate lag structures and attempts to integrate short run dynamics with departures from long run equilibrium relationships the underlying philosophy of this approach is the general to specific methodology popularized by hend ry and his associates e g hendry and ericsson 1991 ericsson et al 1998 the rc approach developed by swamy and tinsley 1980 swamy and tavlas 1992 1995 2000 and christou et al 1996 1998 is aimed at dealing with four major specification problems discussed in section ii that often arise in econometric estimation we use it to shed light on such issues as the stability and predictability of money demand and whether the demand for money was more interest sensitive during the 1930s great depression than in other periods and indeed whether a liquidity trap existed in the 1930s the remainder of this article is divided into three sections section ii discusses the basic money demand specification the data and the vec and rc estimation procedures section iii presents the estimation results both the vec and rc models are estimated using annual data covering 1870 1989 and postsample forecasts are generated over 1990 1997 the models are then reestimated over earlier periods to test how well they forecast in a variety of circumstances including the great depression years for as goldfeld 1992 623 put it in his survey of the money demand literature ultimately of course such models need to stand the forward test of time that is they need to continue to hold outside the period of estimation 3 an aim of the article is to inquire whether two different empirical methodologies can provide a stable long run demand for money function that can perform well in prediction if so this should provide some reassurance about the empirical properties of that function section iv concl udes ii the model data and estimation procedures a basic friedman schwartz specification friedman and schwartz 1982 posited the following money demand function 1 ln m sub t alpha sub 0 alpha sub 1 r sub t alpha sub 2 ln y sub t alpha sub 3 g sub yt u sub t where m

a semi markov model with holdout transshipment policy and phase type exponential lead time in this paper a semi markov decision model of a two location inventory system with holdout transshipment policy is reviewed under the assumption of phase type exponential replenishment lead time rather than exponential lead time the phase type exponential lead time more closely approximates fixed lead time as the number of phases increases unlike past research in this area which has concentrated on the simple transshipment policies of complete pooling or no pooling the research presented in this paper endeavors to develop an understanding of a more general class of transshipment policy in addition we propose an effective method to approximate the dynamic holdout transshipment policy