the effect of supply uncertainty in price setting newsvendor models abstract we consider a price setting newsvendor model in which a firm needs to make joint inventory and pricing decisions before the selling season the supply process is uncertain such that the received quantity is the product of the order quantity and a random yield rate two cost structures are investigated the in house production case in which the firm pays for the input quantity and the procurement case in which the firm pays for the quantity received only our objective is to investigate the effect of yield randomness on optimal decisions and expected profit by using the theory of stochastic comparisons we find that under both cost structures a less variable yield rate leads to a lower optimal price and a higher expected profit moreover we show that in the in house production case a stochastically larger yield rate also results in a lower optimal price and a higher profit but this is not true in the procurement case examples show that the effect of supply uncertainty on optimal order quantity is not universal

optimal supply diversification under general supply risks we analyze a planning model for a firm or public organization that needs to cover uncertain demand for a given item by procuring supplies from multiple sources the necessity to employ multiple suppliers arises from the fact that when an order is placed with any of the suppliers only a random fraction of the order size is usable the model considers a single demand season with a given demand distribution where all supplies need to be ordered simultaneously before the start of the season the suppliers differ from one another in terms of their yield distributions their procurement costs and capacity levels the planning model determines which of the potential suppliers are to be retained and what size order is to be placed with each we consider two versions of the planning model in the first the service constraint model scm the orders must be such that the available supply of usable units covers the random demand during the season with at least a given probability in the second version of the model the total cost model tcm the orders are determined so as to minimize the aggregate of procurement costs and end of the season inventory and shortage costs in the classical inventory model with a single fully reliable supplier these two models are known to be equivalent but the equivalency breaks down under multiple suppliers with unreliable yields for both the service constraint and total cost models we develop a highly efficient procedure that generates the optimal set of suppliers as well as the optimal orders to be assigned to each most importantly these procedures generate a variety of important qualitative insights for example regarding which sets of suppliers allow for a feasible solution both when they have ample supply and when they are capacitated and how various model parameters influence the selected set of suppliers the aggregate order size and the optimal cost values

does it matter how monetary policy is implemented abstract in the u s existing monetary base measures add an adjustment factor for changes in reserve requirement ratios to high powered money implicitly the monetary base assumes that the economic effects of changes in reserve requirements are identical to those due to changes in high powered money theory however does not generally support the prediction that the two policy tools will have the same economic effects structural vars are estimated to compare the short run paths of inflation and output growth under two different types of policy shocks in doing so this analysis gives one a measure of the costs associated with this implicit equivalence assumption the evidence is consistent with the hypothesis that the federal reserve at least partially offsets reserve requirement changes with open market operations and the hypothesis that dynamic explanations of macroeconomic variables are improved by separating reserve requirement changes from other monetary policy moves

the information value of the fomc policy directive under the new operating procedures the federal reserve s federal open market committee fomc meets every one to two months to determine its monetary policy objectives over the near term at the conclusion of each meeting the fomc issues a policy directive to the system s account manager at the new york federal reserve bank specifying short run money growth targets and a federal funds interest rate tolerance range the policy directive is not disclosed to the public until after the next meeting when a new directive becomes effective in an earlier paper o brien 1981 evidence was presented suggesting that immediate disclosure of the fomc policy directives over the period january 1976 june 1979 would have improved the accuracy of market expectations of near term interest rate levels by no more than minor amounts in this paper we examine the information value of the fomc policy directives in predicting near term levels of interest rates urder the federal reserve s revised operating procedures adopted in late october 1979 but modified in late 1982 in the next section the interest rate information value of the fomc policy directive is discussed in terms of a simple money demand and supply model

a note on discount rate policy and the variability of discount window borrowing abstract the purpose of this note is to evaluate the appropriate discount rate policy rules consistent with minimization of the variability of borrowing at the federal reserve discount window in the context of goodfriend s 1983 model of the bank borrowing decision it is demonstrated that either a penalty rate or a subsidy rate policy will produce minimized variability of borrowing so long as the subsidy rate adjusts point for point to changes in the value of the federal funds rate these policy rules are compatible with a policy procedure designed to target borrowed or non borrowed reserves if the fed does not adhere to one of these specific rules minimization of borrowing variability requires an open market procedure in which the fed pegs the federal funds rate

a note on interest on required reserves as an instrument of monetary control abstract the purpose of this paper is to evaluate the potential role of interest on required reserves as a monetary control instrument it is found that an increase in the interest rate paid on reserves held at the federal reserve has counteracting effects on the variability of the money stock hence there is an optimal setting for the interest rate on required reserves that theoretically may include or lie anywhere between the extreme cases of no interest payment and the payment of interest at the maximum feasible level

operational flexibility and financial hedging complements or substitutes we consider a firm that invests in capacity under demand uncertainty and thus faces two related but distinct types of risk mismatch between capacity and demand and profit variability whereas mismatch risk can be mitigated with greater operational flexibility profit variability can be reduced through financial hedging we show that the relationship between these two risk mitigating strategies depends on the type of flexibility product flexibility and financial hedging tend to be complements substitutes i e product flexibility tends to increase decrease the value of financial hedging and vice versa financial hedging tends to increase decrease the value of product flexibility when product demands are positively negatively correlated in contrast to product flexibility postponement flexibility is a substitute to financial hedging as intuitively expected although our analytical results assume perfect flexibility and perfect hedging and rely on a linear approximation of the value of hedging we validate their robustness in an extensive numerical study

the federal reserve s new operating procedures a post mortem abstract although money stock targeting has been the strategic focus of federal reserve policy since the mid 1970 s operating policy the tactics whereby the longer run strategy is implemented over short term intervals has been changed by the federal reserve at least twice over this period a particularly dramatic change in operating policy was announced by the federal reserve in october 1979 this paper provides empirical evidence that settles questions about the nature of this change and suggests that the new operating procedures may have contributed to the heightened interest rate volatility experienced over the 1979 to 1982 period

pricing and the news vendor problem a review with extensions in the newsvendor problem a decision maker facing random demand for a perishable product decides how much of it to stock for a single selling period this simple problem with its intuitively appealing solution is a crucial building block of stochastic inventory theory which comprises a vast literature focusing on operational efficiency typically in this literature market parameters such as demand and selling price are exogenous however incorporating these factors into the mode l can provide an excellent vehicle for examining how operational problems interact with marketing issues to influence decision making at the firm level in this paper we examine an extension of the newsvendor problem in which stocking quantity and selling price are set simultaneously we provide a comprehensive review that synthesizes existing results for the single period problem and develop additional results to enrich the existing knowledge base we also review and develop insight into a dynamic inventory extension of this problem and motivate the applicability of such models

u s treasury bill forward and futures prices for the period 1976 87 forward rates on u s t bills averaged more than 30 basis points above the comparable futures market rates since risk is common to both rates i argue that this difference can be explained by the substitutability of different maturity t bills for money consistent with this hypothesis i find that this difference depends positively on interest rates and the spread between the federal funds and 3 month t bill rates and negatively on the ratio of short term governments to broadly defined money also significant shifts occurred in the relationship in october 1979 and august 1982 coinciding with changes in federal reserve operating procedures copyright 1994 by ohio state university press

joint inventory replenishment and pricing control for systems with uncertain yield and demand we study the joint inventory replenishment and pricing problem for production systems with random demand and yield more specifically we analyze the following single item periodic review model demands in consecutive periods are independent random variables and their distributions are price sensitive the production yield is uncertain so that the quantity received from a replenishment is a random variable whose distribution depends on the production quantity stockouts are fully backlogged our problem is to characterize the optimal dynamic policy that simultaneously determines the production quantity and the price for each period to maximize the total discounted profit we show that the optimal replenishment policy is of a threshold type i e it is optimal to produce if and only if the starting inventory in a period is below a threshold value and that both the optimal production quantity and the optimal price in each period are decreasing in the starting inventory we further study the operational e

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

price and order postponement in a decentralized newsvendor model with multiplicative and price dependent demand we analyze the effect of price and order postponement in a decentralized newsvendor model with multiplicative and price dependent demand wherein the manufacturer sets the wholesale price and possibly offers a buyback rate and the retailer determines the order quantity and retail price such postponement strategies can be used by the retailer by delaying his operational decisions order quantity and retail price until after demand uncertainty is observed we show how the equilibrium values of the contract parameters and profits are affected by i vertical competition ii type of contract wholesale price only or buyback iii demand distribution iv form of the expected demand function and v the timing of the retailer s operational decisions although in most cases postponement is quite beneficial for the channel members we show that for some model parameters due to vertical competition the expected value of perfect information about demand for price postponement and order postponement may be negative for the channel and even surprisingly for both members we also show that when a buyback option is offered neither order postponement nor price postponement has an effect on the equilibrium wholesale price profit allocation ratio between the manufacturer and the retailer and channel efficiency and that the equilibrium wholesale price expected retail price profit allocation ratio between the manufacturer and the retailer and channel efficiency in the model with buyback options under either order or price postponement further coincide with their counterparts in the corresponding deterministic model

the vanishing liquidity effect of money on interest analysis and implications for policy this paper seeks to re examine the effects of money on interest rates the earlier literature on this topic determined fairly well the pattern of response of interest rates to changes in money growth the notable studies of cagan 1972 cagan and gandolfi 1969 and gibson 1970 served to establish the professions stylized pattern as presented in section i section ii presents new evidence on the subject and finds that the old empirical generalizations no longer hold specifically the results suggest that the initial liquidity effect of faster money growth is likely to be offset within the month following the monetary policy change sections iii and iv investigate the reasons for the changing pattern of monetary effects on interest rates and discuss the policy implications of the new pattern

federal reserve operating procedures a survey and evaluation of the historical record since october 1979 comment william poole has produced another thoughtful and thought provoking paper two major conclusions emerge from his work first the instability of growth in m1b since october 1979 can be attributed largely to a reluctance by the federal reserve to permit wide enough swings in the federal funds rate second to correct this problem and to promote greater stability in financial markets and the economy the fed ought to replace lagged with contemporaneous reserve accounting and reform the discount window they should then begin to hit a nonborrowed base or reserves target that grows at a steady rate i will organize my comments around these two conclusions i will not comment directly on the other excellent paper in this session by ralph c bryant i will refer to some of bryant s empirical work though in my discussion of the poole paper poole attributes the continued extensive volatility of m1b growth since october 1979 to efforts by the federal reserve to smooth interest rates he concedes that the fed really has let go the federal funds rate to a very considerable extent but he believes that variability in m1b growth over tonger periods is due primarily to the important role accorded interest rates in federal reserve policy making italics mine he cites four reasons for believing that the post october 1979 targeting procedures qualitatively are not very different from the federal funds targeting procedure followed earlier of the four the most interesting and empirically verifiable is that in nearly one third of the weeks since october 1979 the federal funds rate has averaged within 100 basis points of either the bottom or the top of the widened target range during these weeks the constraint on the funds rate might have prevented the fed from hitting its nonborrowed reserves target poole in fact accepts this view uncritically

resource flexibility with responsive pricing this article studies two types of flexibility used by firms to better respond to uncertain market conditions resource flexibility and responsive pricing we consider a situation in which a single flexible resource can be used to satisfy two distinct demand classes while the resource capacity must be decided based on uncertain demand functions the resource allocation as well as the pricing decision are made based on the realized demand functions we characterize the effects of two key drivers of flexibility demand variability and demand correlation assuming normally distributed demand curve intercepts demand variability creates opportunity costs and with fixed prices decreases the firm s profit we show that with the additional flexibility gained from responsive pricing the firm can maximize the benefits of favorable demand conditions and mitigate the effects of poor demand conditions ultimately profiting from variability positive demand correlation on the other hand remains undesirable under responsive pricing the optimal capacity of the flexible resource is always increasing in both demand variability and demand correlation this contrasts with the scenarios based on fixed prices highlighting the crucial difference that responsive pricing makes in the management of flexible resources we further quantify the value of flexibility for the firm and its customers by considering as a benchmark a firm relying on two dedicated resources the value of flexibility is most significant if the demand levels are highly variable and negatively correlated in such cases the firm benefits from demand variability due to responsive pricing while facing limited demand risk due to resource flexibility finally we endogenize the input price of the flexible resource by considering the pricing decision of the resource supplier

moving to opportunity in boston early results of a randomized mobility experiment this paper examines the short run impacts of a change in residential neighborhood on the well being of low income families using evidence from a program in which eligibility for a housing voucher was determined by random lottery we examine the experiences of households at the boston site of moving to opportunity mto a demonstration program in five cities families in high poverty public housing projects applied to mto and were assigned by lottery to one of three groups experimental offered mobility counseling and a section 8 subsidy valid only in a census tract with a poverty rate of less than 10 percent section 8 comparison offered a geographically unrestricted section 8 subsidy or control offered no new assistance but continued to be eligible for public housing our quantitative analyses of program impacts uses data on 540 families from a baseline survey at program enrollment a follow up survey administered l to 3 5 years after random assignment and state administrative data on earnings and welfare receipt 48 percent of the experimental group and 62 percent of the section 8 comparison group moved through the mto program one to three years after program entry families in both treatment groups were more likely to be residing in neighborhoods with low poverty rates and high education levels than were families in the control group however while members of the experimental group were much more likely to be residing in suburban communities than were those in the section 8 group the lower program take up rate among the experimental group resulted in more families remaining in the most distressed communities households in both treatment groups experienced improvements in multiple measures of well being relative to the control group including increased safety improved health among household heads and fewer behavior problems among boys experimental group children were also less likely to be a victim of a personal crime to be injured or to experience an asthma attack there are no significant impacts of either mto treatment on the employment earnings or welfare receipt of household heads in the first three years after random assignment

on low frequency estimates of long run relationships in macroeconomics abstract a number of recent studies have attempted to test propositions concerning long run economic relationships by means of frequency domain time series techniques that concentrate attention on low frequency comovements of variables the present paper emphasizes that many of these propositions involve expectational relationships that are not inherently related to specific frequencies or periodicities thus the association of low frequency time series test statistics with long run economic propositions is not generally warranted that such an association can be misleading is demonstrated by analysis of examples taken from notable papers by geweke lucas and summers

the 1979 federal reserve policy shift some evidence using causality tests on 6 october 1979 the fomc announced a shift from federal funds rate ffr to nonborrowed reserves nbr targeting the sequence of events preceding this major policy change are well known and require only a brief recounting here prior to the 1979 announcement the fomc implemented monetary policy by confining the ffr to a narrow band about 50 to 100 basis points in width any tendency for the rate to move outside this range was countered by providing more or fewer nbr to the banking system the underlying assumption upon which this strategy was based was that money demand was stable the fed could then control the money stock by altering interest rates thereby moving the public along a fixed money demand function during the mid 1970s however various events in the money market e g income and supply shocks financial innovation and portfolio readjustments lessened the stability of money demand and brought the twin objectives of monetary control and financial market stability into frequent conflict the record shows that these conflicts were usually resolved in favor of interest rate stability rather than monetary control the consequence of ffr targeting was inflation attempts to maintain a stable ffr at the operating level in the face of money demand shifts forced the central bank to exceed its money growth targets for periods long enough to increase nominal aggregate demand in the economy with the adoption of the nbr strategy the fed attempted to achieve better control over inflation by short circuiting the endogenous influences of spending on the growth of the money stock in contrast to the pre 1979 policy spending shocks would now be reflected in ffr movements which would to some extent generate pressures to return money growth to its desired path subsequent to the announced policy shift there was much doubt about whether the federal reserve was successfully executing a nbr plan the gist of this skepticism centers on the belief that the new procedures were technically flawed specifically that reserves targeting when combined with lagged reserve accounting and borrowings projection errors resulted in short run accommodation increased interest rate and money growth volatility

a real model of the world business cycle abstract in this paper a stochastic two country log linear infinite horizon model is used to analyze the generation and transmission of economic fluctuations across countries it is argued that following a country specific supply disturbance production interdependence and unitary elasticities in consumption and production are sufficient to generate comovements in aggregate economic activity investment and trade that are persistent over time and positively correlated across countries however the empirical analysis carried out for the usa japan germany and uk for the 1960 82 period suggests that common shocks rather than trade links are responsible for this pattern of comovements

federal reserve interest rate targeting rational expectations and the term structure abstract the amount of information in the yield curve for forecasting future changes in short rates varies with the maturity of the rates involved indeed spreads between certain long and short rates appear unrelated to future changes in the short rate contrary to the rational expectations hypothesis of the term structure this paper estimates a daily model of federal reserve interest rate targeting behavior which accompanied by the maintained hypothesis of rational expectations explains the varying predictive ability of the yield curve and elucidates the link between fed policy and the term structure

technical note a risk averse newsvendor model under the cvar criterion the classical risk neutral newsvendor problem is to decide the order quantity that maximizes the one period expected profit in this note we consider a risk averse newsvendor with stochastic price dependent demand we adopt conditional value at risk cvar a risk measure commonly used in finance as the decision criterion the aim of our study is to investigate the optimal pricing and ordering decisions in such a setting for both additive and multiplicative demand models we provide sufficient conditions for the uniqueness and existence of the optimal policy comparative statics show the monotonicity properties and other characteristics of the optimal pricing and ordering decisions we also compare our results with those of the newsvendor with a risk neutral attitude and a general utility function

federal reserve control of the money stock comment it is widely believed that the money stock of the united states somehow defined should play a central role in the conduct of federal reserve monetary policy in particular it is believed that the federal reserve should publicly announce a target time path for the money stock and then try to make the actual stock follow that path closely the analytical basis for this approach to federal reserve policy however is seriously deficient unfortunately moreover debate about this approach seldom focuses on the important controversial issues about which views can justifiably differ instead the debate often becomes mired in confusion and false issues one important source of confusion is an inadequate analysis of the operating procedures through which the federal reserve implements its policy from one short run period to the next a second source is a widespread misperception of the economic processes determining the money stock most noneconomists and even many economists seem to believe that the federal reserve can straightforwardly cause the money stock to follow a target path closely month by month provided only that the federal reserve conscientiously tries to do so a third source of confusion is a poor understanding of the two stage decision process implicit in the

the banking industry under uncertain monetary policy abstract the optimal loan decisions of banks are shown to be dependent on the banks rational forecast of the future federal funds rate which in turn is related to the policy rule used by the fed consequently a change in the policy of the fed will alter the reduced form model of the banking industry this result brings into question the fed s ability to predict and control the money stock under the procedure adopted by the fed between october 1979 and september 1982

diversification under supply uncertainty supply chain management is becoming an increasingly important issue especially when in most industries the cost of materials purchased comprises 40 60 of the total sales revenue despite the benefits cited for single sourcing in the popular literature there is enough evidence of industries having two three sources for most parts in this paper we address the operational issue of quantity allocation between two uncertain suppliers and its effects on the inventory policies of the buyer based on the type of delivery contract a buyer has with the suppliers we suggest three models for the supply process model i is a one delivery contract with all of the order quantity delivered either in the current period with probability or in the next period with probability 1 model ii is also a one delivery contract with a random fraction of the order quantity delivered in the current period the portion of the order quantity not delivered is cancelled model iii is similar to model ii with the remaining quantity delivered in the next period we derive the optimal ordering policies that minimize the total ordering holding and penalty costs with backlogging we show that the optimal ordering policy in period n for each of these models is as follows for x a n order nothing for vi n x a n use only one supplier and for x vi n order from both suppliers for the limiting case in the single period version of model i we derive conditions under which one would continue ordering from one or the other or both suppliers for model ii we give sufficient conditions for not using the second more expensive supplier when the demand and yield distributions have some special form for the single period version of models ii and iii with equal marginal ordering costs we show that the optimal order quantities follow a ratio rule when demand is exponential and yields are either normal or gamma distributed

role of risk aversion in price postponement under supply random yield price postponement is an effective mechanism to hedge against the adverse effect of supply random yield however its effectiveness and the resulting production decisions have not been studied for

the policy evaluation problem and the demand for money abstract this paper applies the lucas policy evaluation proposition to the money demand function we find some support for the hypothesis that the decrease in serial correlation of interest rates since the fed policy change in 1979 has resulted in an increase in the estimated elasticity of money demand

the relation between money growth variability and the variability of money about target abstract an increase in the speed at which the fed returns the money stock to its targeted path following a stochastic shock can cause a lower variance of money about the targeted level while causing a greater variance of the growth rate of the money stock

dynamic monetary control and interest rate stabilization abstract interest rate stabilization results in an instrument shortage that complicates monetary control by introducing strategic considerations into the trading desk s decision problem the paper demonstrates that when expected future open market operations influence current bank and depositor behavior an instrument shortage is necessary and sufficient for the commitment policy to be time inconsistent and for the discretionary policy to be suboptimal i e worse than the commitment policy the moving average component of the commitment policy is of higher order than the discretionary policy under either regime the expected value of the representative bank is increasing in the trading desk s emphasis on interest rate stability

infinite horizon strategies for replenishment systems with a general pool of suppliers we consider a general infinite horizon inventory control model that combines demand and supply risks and the firm s ability to mitigate the supply risks by diversifying its procurement orders among a set of n potential suppliers supply risks arise because only a random percentage of any given replenishment order is delivered as useable units the suppliers are characterized by the price they charge and the distribution of their yield factor assuming unsatisfied demand is backlogged the firm incurs as in standard inventory models three types of costs i procurement costs ii inventory carrying costs for units carried over from one period to the next and iii backlogging costs we establish the existence of an optimal stationary policy under both the long run discounted and average cost criteria and characterize its structure assuming each period s inventory level distribution can be approximated as a normal we develop an efficient solution method identifying additional structural properties finally we identify a simple class of heuristic policies that come close to being optimal

first time home ownership in the family life course a west german dutch comparison the transition to first time home ownership is made at increasingly younger ages in both west germany and the netherlands this trend is stronger in the netherlands than in germany however there are also marked differences between the two countries in the extent to which first time home ownership is connected with events in the family life course marriage and childbirth and the availability of resources from the parental family these differences can be understood in terms of differences in house prices housing policy subsidies and other regulations and other differences in the legal and financial systems

monetary policy lessons of recent inflation and disinflation by 1975 most economists agreed that the money demand function in the united states was reasonably stable and could serve as a reliable basis for the formulation of monetary policy those suspicious of monetarism were on the defensive in the light of the apparently inexorable increase of m1 velocity of about three percent per year with deviations of only a few tenths of a percent experience with rising money growth and rising inflation through 1980 only confirmed monetarist views as figure 1 shows all this had changed by 1986 with disinflation in the 1980s m1 velocity departed convincingly from its 1953 79 trend the money demand function seems to have fallen apart and is apparently not a reliable basis for monetary policy after all consequently the first major section following this introduction is devoted to the decline of velocity after 1981 and the demise of the standard money demand function some authors including i believe benjamin friedman conclude that this evidence leaves us so uncertain about the nature of money demand that policymakers cannot rely at all on any presumed money demand regularities in contrast my working hypothesis is that the money demand continues to be a stable function of relatively few variables but that the interest elasticity of money demand is substantially higher than previously thought others have sought money demand explanations in terms of regime shifts but that literature will not be discussed here events have not been kind to keynesian monetary policy positions either keynesians tend to concentrate on interest rates especially real interest rates as the best guide to the effects of monetary policy on the economy the real rate is discussed

an elasticity approach to the newsvendor with price sensitive demand we introduce a measure of elasticity of stochastic demand called the elasticity of the lost sales rate which offers a unifying perspective on the well known newsvendor with pricing problem this new concept provides a framework to characterize structural results for coordinated and uncoordinated pricing and inventory strategies concavity and submodularity of the profit function as well as sensitivity properties of the optimal inventory and price policies are characterized by monotonicity conditions or bounds on the elasticity of the lost sales rate these elasticity conditions are satisfied by most relevant demand models in the marketing and operations literature our results unify and complement previous work on price setting newsvendor models and provide a new tool for researchers modeling stochastic price sensitive demand in other contexts

combined pricing and inventory control under uncertainty this paper addresses the simultaneous determination of pricing and inventory replenishment strategies in the face of demand uncertainty more specifically we analyze the following single item periodic review model demands in consecutive periods are independent but their distributions depend on the item s price in accordance with general stochastic demand functions the price charged in any given period can be specified dynamically as a function of the state of the system a replenishment order may be placed at the beginning of some or all of the periods stockouts are fully backlogged we address both finite and infinite horizon models with the objective of maximizing total expected discounted profit or its time average value assuming that prices can either be adjusted arbitrarily upward or downward or that they can only be decreased we characterize the structure of an optimal combined pricing and inventory strategy for all of the above types of models we also develop an efficient value iteration method to compute these optimal strategies finally we report on an extensive numerical study that characterizes various qualitative properties of the optimal strategies and corresponding optimal profit values

responsive pricing under supply uncertainty consider a retailer orders a seasonal product from a supplier and sells the product over a selling season while the product demand is known to be a linear function of price the supply yield is uncertain and is distributed according to a general discrete probability distribution this paper presents a two stage stochastic model for analyzing two pricing policies no responsive pricing and responsive pricing under the no responsive pricing policy the retailer would determine the order quantity and the retail price before the supply yield is realized under the responsive pricing policy the retailer would specify the order quantity first and then decide on the retail price after observing the realized supply yield therefore the responsive pricing policy enables the retailer to use pricing as a response mechanism for managing uncertain supply our analysis suggests that the retailer would always obtain a higher expected profit under the responsive pricing policy in addition to examining the impact of yield distribution and system parameters on the optimal order quantities retail prices and profits under these two pricing policies we analyze two issues arising from responsive pricing the first issue deals with the case in which the retailer can place an emergency order with an alternative source after observing the realized yield while the second issue deals with a situation in which the retailer has to allocate his order among multiple suppliers

entrance exit and exclusion labour market flows of foreign born adults in swedish divided cities international migrants often occupy subordinate positions inthe labour market or are excluded from it based on unique longitudinaldata this article investigates the socioeconomic mobility ofthe f

ethnic enclaves and the economic success of immigrants evidence from a natural experiment recent immigrants tend to locate in ethnic enclaves within metropolitan areas the economic consequence of living in such enclaves is still an unresolved issue we use an immigrant policy initiative in sweden when government authorities distributed refugee immigrants across locales in a way that may be considered exogenous this policy initiative provides a unique natural experiment which allows us to estimate the causal effect on labor market outcomes of living in enclaves we find substantive evidence of sorting across locations when sorting is taken into account living in enclaves improves labor market outcomes for instance the earnings gain associated with a standard deviation increase in ethnic concentration is in the order of four to five percent

neighbourhood effects and city effects the entry of newly arrived immigrants into the labour market an important debate in current research and policy focuses on the role of urban residential segregation on the social mobility of immigrants much focus has been on neighbourhood effects and on h

intermediate monetary targets and macroeconomic fluctuations it is investigated whether the choice of intermediate target has altered macroeconomic fluctuations and whether the observed changes are consistent with predictions from economic theory since implications from the theoretical literature focus on the effects of structural disturbances an empirical analysis must identify these effects the structural vector autoregressive var technique estimates structural disturbances using restrictions from standard macroeconomic theory based on descriptions of actual targeting procedures by insiders to federal reserve policy decisions the intermediate target for the united states is identified as the interest rate from 1951 to 1969 and money from 1970 to 1986 var models are estimated over each subsample to assess whether the estimated structural disturbances cause endogenous variables to behave as economic theory predicts tests are also performed to assess whether or not the targeting rule affects the variance of endogenous variables attributable to structural sh

selecting a portfolio of suppliers under demand and supply risks we analyze a planning model for a firm or public organization that needs to cover uncertain demand for a given item by procuring supplies from multiple sources each source faces a random yield factor with a general probability distribution the model considers a single demand season all supplies need to be ordered before the start of the season the planning problem amounts to selecting which of the given set of suppliers to retain and how much to order from each so as to minimize total procurement costs while ensuring that the uncertain demand is met with a given probability the total procurement costs consist of variable costs that are proportional to the total quantity delivered by the suppliers and a fixed cost for each participating supplier incurred irrespective of his supply level each potential supplier is characterized by a given fixed cost and a given distribution of his random yield factor the yield factors at different suppliers are assumed to be independent of the season s demand which is described by a general probability distribution determining the optimal set of suppliers the aggregate order and its allocation among the suppliers on the basis of the exact shortfall probability is prohibitively difficult we have therefore developed two approximations for the shortfall probability although both approximations are shown to be highly accurate the first based on a large deviations technique ldt has the advantage of resulting in a rigorous upper bound for the required total order and associated costs the second approximation is based on a central limit theorem clt and is shown to be asymptotically accurate whereas the order quantities determined by this method are asymptotically optimal as the number of suppliers grows most importantly this clt based approximation permits many important qualitative insights

the return of the liquidity effect a study of the short run relation between money growth and interest rates in this article i use band pass filters to investigate the short run relationship between money growth and interest rates i find a negative correlation between short run movements in money growth and interest rates which i interpret as evidence that the liquidity effect dominates the anticipated inflation effect

technical note optimal product pricing and component production quantities for an assembly system under supply uncertainty we consider an assemble to order system where one of the components faces uncertainty in the supply process in which the actual available quantity is equal to some random fraction of the production quantity demand is assumed to be price dependent we analyze how the supply uncertainty of one component affects the product pricing and production quantities of all the components under the assembly structure we show that it is profitable for the firm to assemble the product only if the product price exceeds a certain threshold this price threshold increases as the unit cost of each component or the degree of variability of the supply reliability distribution increases but it is independent of the underlying demand function and demand distribution also the optimal product price decreases as supply uncertainty decreases we further show that under deterministic demand the components can be managed independently such that the production quantity or unit cost of the component with supply uncertainty does not affect the optimal production quantity of the other components as long as it is profitable to assemble the product however when demand is stochastic the optimal production quantity of each component depends on the supply reliability distribution as well as the unit costs of the other components for a fixed product price the optimal production quantities of the components are smaller when the unit product price is low and they are higher when the unit product price is high as compared to the case with no supply uncertainty

coordinating inventory control and pricing strategies with random demand and fixed ordering cost the finite horizon case we analyze a finite horizon single product periodic review model in which pricing and production inventory decisions are made simultaneously demands in different periods are random variables that are independent of each other and their distributions depend on the product price pricing and ordering decisions are made at the beginning of each period and all shortages are backlogged ordering cost includes both a fixed cost and a variable cost proportional to the amount ordered the objective is to find an inventory policy and a pricing strategy maximizing expected profit over the finite horizon we show that when the demand model is additive the profit to go functions arek concave and hence an s s p policy is optimal in such a policy the period inventory is managed based on the classical s s policy and price is determined based on the inventory position at the beginning of each period for more general demand functions i e multiplicative plus additive functions we demonstrate that the profit to go function is not necessarilyk concave and an s s p policy is not necessarily optimal we introduce a new concept the symmetrick concave functions and apply it to provide a characterization of the optimal policy

1979 1982 rules or discretion in monetary policy gregory hoelscher what determined m1 growth from november 1979 through october 1982 a reaction function is developed and tested which ascribes the level of ml to two fed motives one is the fed s desire to hit its money growth targets the other is to carry out a counter cyclical short run monetary policy both motives are found to be significant during the period this evidence is consistent with the contention of some economists that the period was not a valid test of monetarist policy rules i introduction in october of 1979 the federal reserve system announced that it would use a new operating procedure that would allow it to place strong emphasis on controlling ml this policy shift from an interest rate target regime to a non borrowed reserves target regime was widely considered as tacit acceptance of the monetarist doctrine monetarists had been calling for a policy of stable gradually declining and pre announced money growth paths the change in operating procedure was designed to give the fed greater control over ml and to dramatize the fed s commitment to slowing money growth and inflation at the time many expected the new operating policy to result in a more stable money growth path at the expense of some short term interest rate variability the rate of inflation fell from 13 3 percent in 1979 to 3 9 percent in 1982 but the variability of both short term interest rates and of money growth increased substantially ore importantly the economy slipped into a brief recession in early 1980 and a longer and much more severe one in late 1981 by october 1982 the fed announced that it would de emphasize ml as a target variable but would continue to monitor the broader monetary aggregates thus a three year monetarist inspired experiment came to an end benjamin friedman 1984 and bryant 1983 argue that the events of 1979 82 demonstrate that monetarism as a policy guide is inadequate other economists disagree with these criticisms milton friedman 1984 mccallum 1984 and poole 1982 blame the high variance of monthly or quarterly growth rates in m1 for the poor post 1979 performance of the economy this paper assesses formally the determinants of m1 growth during the 1979 82 period if the fed was attempting to use m1 to fine tune the real sector then the argument that the 1979 82 period was not a valid test of the monetarist approach to monetary policy is that much stronger on the other hand if changes in m1 cannot be explained by fine tuning motives then perhaps the period does represent a test of monetarist policies the next section discusses the reaction function used in the paper section iii describes the data and the test results the evidence is consistent with the hypothesis that the money growth targets and either of two measures of real economic performance the unemployment rate and industrial production were significant determinants of fed policy during the late 1979 to late 1982 period section iv contains conclusions ii methodology the empirical tests use a reaction function the use of a reaction function does not imply that the federal reserve board or the open market committee explicitly acts in accordance with the function the reaction function is instead an as if assumption the fed is assumed to act as if it minimizes a loss function reaction functions have been estimated by a large number of authors barth sickles and wiest 1982 summarize many of the papers published in 1978 and earlier they report that unemployment and to a lesser extent inflation were most commonly cited as significant determinants of federal reserve policy during various portions of the 1952 77 period more recent papers by abrams froyen and waud 1980 levy 1981 allen and smith 1983 bradley 1984 witte 1984a 1984b and bradley and potter 1986 have extended the literature by including additional variables and time periods in the analysis

technical note price setting newsvendor problems with uncertain supply and risk aversion the price setting newsvendor problem which models the economic trade offs associated with uncertain demand of a perishable product is fundamental to supply chain analysis however in settings such as agriculture there is significant economic risk associated with supply uncertainty we analyze how risk aversion and the source of uncertainty demand and or supply affect tractability and optimal decisions we find that concavity of the objective function is preserved under the introduction of risk aversion if the source of uncertainty is demand but it is not necessarily preserved if the source of uncertainty is supply we identify a structural difference that explains this result and show that this difference can lead to opposing directional effects of risk aversion on optimal decisions

price versus production postponement capacity and competition this article presents a comparative analysis of possible postponement strategies in a two stage decision model where firms make three decisions capacity investment production inventory quantity and price typically investments are made while the demand curve is uncertain the strategies differ in the timing of the operational decisions relative to the realization of uncertainty we show how competition uncertainty and the timing of operational decisions influence the strategic investment decision of the firm and its value in contrast to production postponement price postponement makes the investment and production inventory decisions relatively insensitive to uncertainty this suggests that managers can make optimal capacity decisions by deterministic reasoning if they have some price flexibility under price postponement additional postponement of production has relatively small incremental value therefore it may be worthwhile to consider flexible ex post pricing before production postponement reengineering while more postponement increases firm value it is counterintuitive that this also makes the optimal capacity decision more sensitive to uncertainty we highlight the different impact of more timely information which leads to higher investment and inventories and of reduced demand uncertainty which decreases investment and inventories our analysis suggests appropriateness conditions for simple make to stock and make to order strategies we also present technical sufficiency and uniqueness conditions under price postponement these results extend to oligopolistic and perfect competition for which pure equilibria are derived interestingly the relative value of operational postponement techniques seems to increase as the industry becomes more competitive

trade interdependence and the international business cycle a stochastic general equilibrium model of the world economy is developed to analyze the contribution of trade interdependence to international business cycles we test some of the implications of the model using data from ten major industrial countries and a variety of detrending techniques to calculate the cyclical component of output we find that the significance of trade in the transmission of economic disturbances across countries is not robust to the choice of the detrending method in general the role of trade interdependence is moderate and seem to have been stronger in the period before 1973

long and short term interest rates in a risky world abstract the paper develops and tests a general equilibrium model in which variability or risk affects the choice of portfolios our measures of variability include only the variability of unanticipated growth in monetary and non monetary aggregates and our tests use data ending with the change in federal reserve procedures in october 1979 we find that increased variability of unanticipated money growth raises demands for debt and money and reduces the demand for real capital interest rates on both short and long term debt rise by a risk premium we estimate the size of the risk premium before and after the october 1979 change and we show that the change in federal reserve procedures moved the economy to a less efficient point

integrating dynamic pricing and replenishment decisions under supply capacity uncertainty this paper examines an integrated decision making process regarding pricing for uncertain demand and sourcing from uncertain supply which are often studied separately in the literature our analysis of the integrated system suggests that the base stock list price policy fails to achieve optimality even under deterministic demand instead the optimal policy is characterized by two critical values a reorder point and a target safety stock under this policy a positive order is issued if and only if the inventory level is below the reorder point when this happens the optimal order and price are coordinated to achieve a constant target safety stock which aims at hedging the demand uncertainty we further investigate the profit improvement obtained from deploying dynamic pricing as opposed to static pricing our results indicate that either supply limit or supply uncertainty may induce a significant benefit from dynamic pricing and the compound effect of supply limit and uncertainty can be much more pronounced than the individual effects whether or not the supply capacity is limited has a major implication on the value of dynamic pricing under unlimited supply dynamic pricing is more valuable when procurement cost is high or when demand is more sensitive to price with limited supply however the capacity restriction tends to be relaxed reducing the value of dynamic pricing