optimal lot size model for deteriorating items with demand rate dependent on displayed stock level dsl and partial backordering in this paper we consider the problem of determining the lot size of a single deteriorating item with the demand rate dependent on displayed stock level selling price of an item and frequency of advertisement in the popular electronic and print media also through the sales representatives shortages if any are allowed and partially backlogged with a variable rate which depends on the duration of waiting time upto the arrival of next lot here the transportation cost for replenishing the goods is considered explicitly and the storage capacity of the showroom shop is assumed to be limited finite according to the relative size of the stock level dependency demand parameters and the storage capacity of the showroom shop different scenarios with sub scenarios have been mentioned and solved with the help of grg generalised reduced gradient method and the computational procedure the convexity analysis is done by showing the average profit function in each case as pseudo concave to illustrate the results and its significant features a numerical example is given finally to study the effect of changes of demand parameters deterioration backlogging parameters and mark up rate on the maximum initial stock level shortage level frequency of advertisement per cycle along with the maximum average profit are presented numerically

a money demand equation for brazil abstract the estimates for the money demand equation reported below are based on quarterly time series for brazil for the 1966 i 1979 iv period they show that the long run income elasticity of the demand for money is roughly unitary and the rate of interest does affect the demand for money exclusion of the latter variable therefore leads to biased estimates of the coefficients of the money demand equation the empirical evidence also points out that the rate of inflation affects the demand for money only to the extent that it is necessary to change nominal cash balances to adjust cash holdings to their desired level either nominal interest rates capture the expected inflation rates or goods inventories are not an important alternative to holding money in brazil

a deterministic inventory model for deteriorating items with stock dependent demand rate abstract a deterministic inventory model is developed by assuming that the demand rate is stock dependent and the items deteriorate at a constant rate the expression for the average net profit over one production run is derived and its optimization with respect to the decision variables q initial stock and t duration of a production cycle is carried out this leads to two highly nonlinear equations which are solved by using a subroutine neqnf in imsl math library in cyber 180 480a computer system the optimal solution so derived is compared with that for the no deterioration 0 case sensitivity of the optimal solution to changes in parameter values is examined several aspects of the functional form for the demand rate are considered in a separate section finally the salient features of the problem and its solution are discussed in brief

labor costs and manufactured exports in developing countries an econometric analysis abstract policies addressing the effects of labor market distortions on exports have not relied upon empirical evidence on the impact of labor costs using an econometric model this paper analyses the effect of labor costs on manufactured exports in 20 less developed countries concluding that labor costs significantly affect manufactured exports the explanatory power of manufacturing capacity is significant in all the countries and in the majority of them export elasticities with respect to export prices and to the price of imported intermediates are also significant pooling cross section and time series data the effect of labor market distortions on manufactured exports is analyzed the conclusion is that the effect of labor market distortions is significant and negative supporting the idea that deregulating the labor market is essential to promote exports

interpreting an error correction model partial adjustment forward looking behaviour and dynamic international money demand an error correction model is derived from a stochastic dynamic programming problem incorporating rational expectations a parametric restriction is derived that allows a test for the theoretical proposition that the optimal strategy behind the error correction from entails the failure to asymptotically close the gap between the choice variable and the growing target this is accomplished by nesting a partial adjustment model with forward looking expectations within the error correction paradigm the counterintuitive behaviour embodied in the error correction model is not supported by the data in the context of a cross country comparison of cash balances relationships

a note on eoq models for deteriorating items under stock dependent selling rate abstract in 1995 padmanabhan and vrat presented inventory models for deteriorating items with stock dependent selling rate and derived the profit functions without backlogging and with complete backlogging first this paper develops the necessary and sufficient conditions of the existence and uniqueness of the optimal solutions of the profit per unit time functions without backlogging and with complete backlogging second this paper explains that it is appropriate to use the newton raphson method to find the optimal solutions of the profit functions per unit time in both situations modelled

an inventory model for deteriorating items with stock dependent consumption rate and shortages under inflation and time discounting this paper derives an inventory model for deteriorating items with stock dependent consumption rate and shortages under inflation and time discounting over a finite planning horizon we show that the total cost function is convex with the convexity a simple solution algorithm is presented to determine the optimal order quantity and the optimal interval of the total cost function the results are discussed with a numerical example and particular cases of the model are discussed in brief a sensitivity analysis of the optimal solution with respect to the parameters of the system is carried out

the sudan demand for international reserve a case of a labour exporting country an empirical analysis of the demand for international reserves in the sudan is presented based on the error correction model this model is parametrically rich enough to allow the division of the effects into long run influences short term adjustments and proportional equilibrium impacts beside addressing conventional issues in reserve demand literature the model explicitly incorporates the impact on reserve demand of remittances transferred by sudanese nationals working abroad and the impact due to money market disequilibrium the demand function is found to be stable and characterized by constant returns to scale copyright 1990 by the london school of economics and political science

inventory models with inventory level dependent demand a comprehensive review and unifying theory marketing researchers and practitioners have long recognized the demand of many retail items is proportional to the amount of inventory displayed recently two distinct types of inventory control models reflecting this relationship have appeared in the literature models in which the demand rate of an item is a function of the initial inventory level and those in which it is dependent on the instantaneous inventory level we present a comprehensive overview of this literature and demonstrate the equivalence of the two types of models through the use of a simple periodic review model an alternative approach to sensitivity analysis for inventory models with inventory level dependent demand is also presented

an inventory model for deteriorating items with stock dependent demand rate abstract this paper discusses an inventory model with an inventory level dependent demand rate followed by a constant demand rate for items deteriorating at a constant rate where the terminal condition of zero inventory at the end of the scheduling period has been relaxed sensitivity of the decision variables to changes in the parameter values is examined and the effects of these changes on the optimal policy are discussed in brief

a production inventory model in an imperfect production process abstract the paper develops a model to determine the optimal product reliability and production rate that achieves the biggest total integrated profit for an imperfect manufacturing process the basic assumption of the classical economic manufacturing quantity emq model is that all manufacturing items are of perfect quality the assumption is not true in practice most of the production system produces perfect and imperfect quality items in some cases the imperfect quality non conforming items are reworked at a cost to restore its quality to the original one rework cost may be reduced by improvements in product reliability i e decreasing in product reliability parameter lower value of product reliability parameter results in increase development cost of production and also smaller quantity of nonconforming products the unit production cost is a function of product reliability parameter and production rate as a result higher development cost increases unit production cost the problem of optimal planning work and rework processes belongs to the broad field of production inventory model which deals with all kinds of reuse processes in supply chains these processes aim to recover defective product items in such a way that they meet the quality level of good item the benefits from imperfect quality items are regaining the material and value added on defective items and improving the environment protection in this point of view a model is introduced here to guide a firm industry in addressing variable product reliability factor variable unit production cost and dynamic production rate for time varying demand the paper provides an optimal control formulation of the problem and develops necessary and sufficient conditions for optimality of the dynamic variables in this purpose the euler lagrange method is used to obtain optimal solutions for product reliability parameter and dynamic production rate finally numerical examples are given to illustrate the proposed model

an inventory model with both stock dependent demand rate and stock dependent holding cost rate abstract in this paper we develop an inventory model under a stock dependent demand rate and stock dependent holding cost rate with relaxed terminal conditions shortages are allowed and partially backlogged in the model the purpose of this study is to determine the optimal order quantity and the ending inventory level such that the total profit per unit time is maximized for the retailer we first establish a proper model for a mathematical formulation then we develop several theoretical results and provide the decision maker with an algorithm to determine the optimal solution finally numerical examples are provided to illustrate the solution procedure and a sensitivity analysis of the optimal solution with respect to major parameters is carried out

the search for a stable money demand function a survey of the post 1973 literature phe question of whether the demnand function for money is stable is one of the most important recurring issues in the theory and application of macroeconomic policy what is being sought in a stable demand function is a set of necessary conditions for money to exert a predictable influence on the economy so that the central bank s control of the money supply can be a useful instrument of economic policy as such the notion of a stable demand function appears to involve three key elements e g john t boorman 1976 p 317 and david e w laidler 1977 pp 34 35 first the demand for money relation should be highly predictable in a statistical sense as measured by the usual goodness of fit statistics precision of estimated coefficients and presumably its ability to forecast accurately out of sample second a stable demand function for money has relatively few arguments a relationship that requires knowledge about a large number of variables in order to pin it down is in effect not predictable finally the variables that appear as arguments in the function should represent significant links to spending and economic activity in the real sector in sum a stable demand function for money means that the quantity of money is predictably related to a small set of key variables linking money to the real sector of the economy the importance of a stable money demand function for monetary policy can be illustrated with the standard is lm model in which interest rates and gnp are the endogenous variables in this context a stable demand function for money translates into a well defined relationship between money interest rates and gnp

do exchange rate changes have symmetric or asymmetric effects on the demand for money in turkey as a result of the research conducted by nobel laureate robert mundell 1963 most studies estimating the demand for money today do include the exchange rate in their specification to account for currency substitution previous studies that did this for the turkish demand for money assumed that exchange rate changes do have symmetric effects on the demand for money in turkey in this article we question this assumption by using the nonlinear ardl approach we show that indeed exchange rate changes do have short run and long run asymmetric effects on the m1 demand for money introducing nonlinearity also yields a stable money demand

economic policy uncertainty and demand for money in australia abstractthe demand for money has received a great deal of attention in the empirical literature this literature however has emphasized factors such as interest rate income inflation rate and e

an error correction approach to money demand the case of sudan abstract an empirical analysis of money demand behavior in sudan is presented based on the dynamic error correction model a theoretical basis for the model is offered which allows an explicit parameterized division of effects into long run influences short term adjustments and proportional equilibrium conditions we refute previous claims that income and price effects may be abnormally high in sudan in part by accounting for both foreign exchange and inflationary influences

an optimal replenishment policy for non instantaneous deteriorating items with stock dependent demand and partial backlogging abstract in this study we consider a problem of determining the optimal replenishment policy for non instantaneous deteriorating items with stock dependent demand in the model shortages are allowed and the backlogging rate is variable and dependent on the waiting time for the next replenishment the necessary and sufficient conditions of the existence and uniqueness of the optimal solution are shown as the special cases the results for the models with instantaneous or non instantaneous deterioration rate and with or without shortages are derived further we analytically identify the best circumstance among these special cases based on the minimum total relevant cost per unit time sensitivity analysis of the optimal solution with respect to major parameters is carried out finally four numerical examples are presented to demonstrate the developed model and the solution procedure

asset substitution money demand and the inflation process in brazil various domestic financial assets in brazil have provided relatively liquid nonmonetary alternatives monthly money demand estimates which include domestic asset opportunity costs and take account of t bill repurchase agreements in a dynamic error correction model demonstrate the importance of domestic substitutes in explaining money holdings money demand appears responsive and stable moreover t bills and indexed bonds have acted as an alternative to central bank liabilities as a source of finance for government deficits evidence indicates that the initial financing of government deficits through bonds bills and other nonmonetary liabilities may explain why money lags price shocks rather than vice versa copyright 1989 by ohio state university press

an optimal production inventory model for deteriorating items with multiple market demand the global markets of today offer more selling opportunities to the deteriorating items manufacturers but also pose new challenges in production and inventory planning from a production management standpoint opportunities to exploit the difference in the timing of the selling season between geographically dispersed markets for deteriorating items are important to improving a firm s profitability in this paper we examined the above issue with an insightful production inventory model of a deteriorating items manufacturer selling goods to multiple markets with different selling seasons we also provided a solution procedure to find the optimal replenishment schedule for raw materials and the optimal production plan for finished products a numerical example was then used to illustrate the model and the solution procedure finally sensitivity analysis of the optimal solution with respect to major parameters was carried out

an eoq model with state dependent demand rate we present an eoq type model in which the demand rate is a function of the inventory level the demand functions and holding cost functions considered are quite general in particular we focus on two types of demand rate functions a piecewise constant function and a family of exponential functions the paper includes analysis of the problem optimization and sensitivity analysis we also extend the model by adding randomness to the order sizes

a re examination of the demand for money in small developing economies this paper re examines the money demand function in three small open economies of asia korea pakistan and singapore in addition to using the relatively new procedure of error correction modelling the roles of variables such as a the expected change in the exchange rate b foregin interest rates and c foreign exchange risks on money demand are examined in testing the importance of these variables in the money demand function special attention is paid to testing the assumptions of the classical linear regression model the sample period for each country spans from 1973 1 through 1990 1 the empirical results suggest that the error correction specification performs very well in addition to the traditional variables the results suggest that at least some measure of foreign monetary developments appear to have some significant effect on money demand behaviour in these small developing economies

an optimal procurement policy for items with an inventory level dependent demand rate and fixed lifetime abstract this paper investigates an optimal procurement policy for items with an inventory level dependent demand rate and fixed lifetime the demand rate is assumed to be a function of current inventory level and each unit has its fixed expiry date so any units which remain unused by their expiry date are considered outdated and must be disposed of for the system presented a mathematical model and solution methodology were developed sensitivity of the decision variables to changes in the parameter values is examined and future research needs are discussed in brief

a two echelon inventory distribution system with power demand pattern and backorders abstract this paper addresses the implications of considering power demand pattern and backorders in the one warehouse n retailer problem specifically we assume that items at the retailers are withdrawn from the inventory following a power pattern the objective function consists of the sum of ordering holding and backordering costs at all installations this objective function depends on the class of inventory policies that we choose for the formulation of the problem in general obtaining the cost function is an arduous task since the average inventory at the warehouse could be difficult to determine however if we apply single cycle policies the computation of the total average cost becomes possible under these assumptions we show that the one warehouse n retailer system with power demand pattern and backorders can be formulated as a mixed non linear programming problem

stack them high let em fly lot sizing policies when inventories stimulate demand in some retail contexts stocking large quantities of inventory may not only improve service levels but can also stimulate demand for products having demand rates that increase with inventory levels we analyze the effect of stocking decisions on firm profitability to develop managerial insights regarding the structure of the optimal inventory policy and to understand how this policy differs from traditional approaches when inventories stimulate demand iteratively applying the standard economic order quantity eoq model by setting the demand rate parameter equal to the observed average demand rate in prior cycles yields an equilibrium order quantity that is robust to demand parameter misestimation but is suboptimal the profit maximizing policy orders larger quantities and can replenish inventory even before on hand stock fully depletes using an extension of a standard inventory dependent demand model from the literature we first provide a convenient characterization of products that require early replenishment we demonstrate that the optimal cycle time is largely governed by the conventional trade off between ordering and holding costs whereas the reorder point relates to a promotions oriented cost benefit perspective we show that the optimal policy yields significantly higher profits than cost based inventory policies underscoring the importance of profit driven inventory management

another visit to the cagan model of money demand the latest russian experience abstract this paper investigates empirically the cagan style money demand function for russia during the recent hyperinflation era 1992 1994 using the johansen multivariate cointegration test results indicate that rate of change of exchange rate currency depreciation is required in the demand function for real m2 and real currency in order to obtain a stationary long run relationship error correction model results show that there exists a bidirectional causality between real money balances and determinants of real money demand including currency depreciation exchange rate sensitivity of the demand for money indicates currency substitution

exchange rate sensitivity of the demand for money in developing countries there is consensus among researches that under the present floating exchange rate system although developing countries peg their exchange rate to a major currency they cannot avoid fluctuation in their effective exchange rates as long as major currencies fluctuate against one another few authors have investigated the effects of changes in effective exchange rates of developing countries on their imports exports trade balance demand for international reserves inflation etc in this paper we try to inestigate the effects of effective exchange rates of developing countries on their demand for money previous authors who have estimated a money demand function inclusive of an exchange rate variable bilateral or effective have restricted themselves to industrial countries only by using quarterly data over the 1973 85 period it is shown that in most developing countries while the short run effcts of depreciation could be in either direction its long run effects are negative indicating that deprecia

a critical assessment of supply demand models of agricultural trade we offer a critical assessment of static deterministic reduced form supply demand sd models of agricultural trade a commonly used and well documented model has significant limitations no explicit treatment of factor mobility between farm and nonfarm sectors nonzero profits in some sectors no substitutability among feedstuffs in livestock sectors violation of the law of one price small marketing margins for some commodities and incomplete coverage of the agricultural sector such limitations have significant impacts on the magnitude and direction of projected world price and welfare changes we believe agricultural policy analysis should first focus on the remediation of these limitations before proceeding to more complex issues like dynamics and uncertainty