optimal time based consolidation policy with price sensitive demand abstract we consider a single item inventory system where shipments are consolidated to reduce the transportation cost using a time based consolidation policy and develop a mathematical model to obtain the optimal price replenishment quantity and dispatch cycle to maximize the total profit the long run average profit is computed and the optimality properties are obtained using the optimality properties we develop an efficient algorithm to obtain the optimal values of price replenishment quantity and dispatch cycle for the proposed policy we then extend our results to consider quantity discount of unit dispatch cost in order to compare the performances of the proposed policy with the optimal quantity based policy extensive numerical experiments are conducted and the total profit and the customer waiting time that represents quality of service are compared we also propose the quantity time based policy which is a hybrid approach and the numerical results show that additional profit can be obtained without sacrificing quality of service

optimal pricing and lot sizing under conditions of perishability finite production and partial backordering and lost sale abstract perishable products constitute a sizable component of inventories common questions in a production and selling situation involving a perishable or a non perishable product are what should be the price and what should be the size of the replenishment when demand for the product is price sensitive pricing and lot sizing decisions are interdependent similarly when a product is highly perishable the demand may need to be backlogged to avoid costs due to deterioration i e perishability and backlogging are complementary conditions in this paper we consider the pricing and lot sizing problem for a perishable good under finite production exponential decay and partial backordering and lost sale the backlogging phenomenon in the literature is often modeled using backordering and lost sale costs these cost parameters however are not easy to estimate in practice in this paper we use a new approach to model backlogging of demand in this approach customers are viewed to be impatient the backlogging option gets used only when it is economic to do so we extend the analysis presented for a perishable product to the case in which the product is non perishable

pricing and scheduling decisions with leadtime flexibility this paper studies a problem faced by a manufacturer who has the ability to set prices to influence demand reject orders and set leadtimes or due dates for accepted orders we present decision models that integrate pricing and production decisions for the cases where the manufacturer charges the same price or different prices to different customers through numerical analyses we present insights regarding the benefits of price customization leadtime and inventory flexibilities in various demand environments

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

an economic order quantity model with partial backordering and all units discount abstract the classic economic order quantity model assumes that the unit purchasing cost is not based on the order quantity in practice a supplier may offer purchasers an all units discount we develop a model and solution procedure for the eoq with all unit discounts and partial backordering at a constant rate we show and illustrate with a numerical example how that model can be used to find the solution for the eoq with discount and full backordering a multi factor experiment is used to gain insights into the improvement in performance of the proposed procedure relative to using the basic eoq or the eoq with full backordering and to identify the model parameters that have the greatest impact on the model s performance

specialization transactions technologies and money growth this paper develops a differentiated product model with endogenous specialization in which either money or a costly alternative transactions technology can be used for market purchases we discuss the real effects of monetary growth in this model which differ from those in standard cash in advance models and the implied interest sensitivity of money demand in general equilibrium

partial backlogging inventory lot size models for deteriorating items with fluctuating demand under inflation abstract in this paper the traditional inventory lot size model is extended to allow not only for general partial backlogging rate but also for inflation the assumptions of equal cycle length and constant shortage length imposed in the model developed by moon et al moon i giri b c ko b 2005 economic order quantity models for ameliorating deteriorating items under inflation and time discounting european journal of operational research 162 3 773 785 are also relaxed for any given number of replenishment cycles the existence of a unique optimal replenishment schedule is proved and further the convexity of the total cost function of the inventory system in the number of replenishments is established the theoretical results here amend those in yang et al yang h l teng j t chern m s 2001 deterministic inventory lot size models under inflation with shortages and deterioration for fluctuating demand naval research logistics 48 2 144 158 and provide the solution to those two counterexamples by skouri and papachristos skouri k papachristos s 2002 note on deterministic inventory lot size models under inflation with shortages and deterioration for fluctuating demand by yang et al naval research logistics 49 5 527 529 finally we propose an algorithm to find the solution and obtain some managerial results by using sensitivity analyses

money as the mechanism of exchange abstract the existence and use of money remained an embarrassing puzzle for monetary analysis we observe over man s history that social groups without generally accepted media of exchange exhibit poor survival characteristics most social groups do not use assets or commodities at random in the execution of exchanges one observes that a small subset of assets is dominantly used in transactions these transaction dominating assets are usually referred to as money the literature contains many suggestive attempts to explain the emergence and role of money the classic writers made passing references in somewhat pictorial language to the extension markets and increasing labor productivity induced by the use of a general medium of exchange this idea has never been systematically developed however karl brunner 1971

endogenous transfer institutions in overlapping generations abstract we characterize the set of equilibrium transfers between overlapping generations when transfer institutions are endogenous in stationary economies pareto improving transfers require institutions cost as much to construct as they convey even if less costly institutions exist that make the same transfer if institutions can be built upon they may cost less and convey more but transfers may become excessive interpreting such institutions as social security we introduce private saving with time social security crowds out savings still the potential to save limits any excess transfer endogenous costly to create gold money institutions are examined and the role of compulsion in evolving to costless to create fiat currency detailed

deteriorating inventory model with quantity discount pricing and partial backordering inventory models with quantity discount pricing and partial backordering although common in practice have received very little attention from researchers the objective of this study is to develop a deterministic inventory model with quantity discount pricing and partial backordering when the product in stock deteriorates with time most retailers make pricing decisions of their products at certain times of the year and these decisions affect demand in this study the demand rate is assumed to decrease as price for the product increases unlike traditional inventory models that seek to minimize cost the objective of this study is to maximize profit the findings of this study are particularly relevant to retailers of deteriorating products in a competitive environment a numerical example is given to illustrate the theory

optimal stopping and restarting production times for an eoq model with deteriorating items and time dependent partial backlogging abstract yan and cheng j operational res soc 49 1998 1288 1295 presented a general production inventory model with production rate product demand rate and deterioration rate all considered as functions of the time their model allows for shortages and partial backlogging of the unsatisfied demand at a constant rate in this paper we extend the results of yan and cheng to cover the case where the backlogging rate is a time dependent function and we propose an algorithm for the solution of this problem we also propose some conditions which we believe to be necessary for the validity for some of yan s and cheng s statements the paper closes with numerical examples which cover each one of the cases considered in the paper

economic organization with limited communication this paper presents formal stylized representations of communication accounting systems oral assignment portable object written message and telecommunication systems are considered the environments that allow this formalization are characterized by spatial separation private information and a need to keep track of past actions transfers and shocks in environments that have spatial separation and private information beneficial multilateral arrangements can depend critically on agents ability to communicate to one another values of contemporary shocks and to keep track of histories of past transfers or past announced shocks this paper formalizes this idea and focuses on com

inventory returns and special sales in a lot size system with constant rate of deterioration abstract the problem of returning or of selling the inventory excess to optimal stock level is considered for deteriorating items two inventory models viz the infinite and the finite horizon models are developed in which the deterioration is assumed to be a constant fraction of the on hand inventory both the models are developed under the assumptions of instantaneous delivery and no shortages when there is no deterioration the developed models are related to the corresponding inventory models for non deteriorating items examples are given to illustrate the derived results

liquidity quality production cost and welfare in a search model of money this paper examines a search model of money with divisible commodities of high and low quality while keeping the assumptions of indivisible money and unit inventory constraint with no direct barter and a higher fixed cost of producing high relative to low quality an increase in the money stock encourages the production of high quality output by trading off the larger trading opportunities against the significance of higher fixed cost as long as the fixed cost differential between high and low quality is sufficiently small relative to the utility gain from high quality consumption the quality improvement outweighs the negative effect of higher money stocks on aggregate production and hence implies higher welfare the most important function of money is its role as a medium of exchange wicksell 1906 1967 p 17 defined a general medium of exchange to be an object which is habitually and without hesitation taken by anybody in exchange for any commodity the main challenge facing monetary theory is to construct a model which permits the object s role in exchange to be endogenous 1 kiyotaki and wright 1991 1993 seems to be the first fully coherent model which specifies the environment and equilibrium concept in a way that does not force at the outset the assumption on which objects will play a special role in trade the kiyotaki wright model departs from the physical environment of the standard general equilibrium model through the assumption that trading histories are private information the medium of exchange role of money is obtained as an outcome of nash equilibrium together with some bargaining rule in pairwise random meetings however the standard kiyotaki wright model yields an undesirable welfare implication that an increase in the money stock eventually leads to a decrease in welfare because of a decrease in the number of agents who get to consume in a given period the same welfare property is obtained in the models with divisible commodities such as trejos and wright 1995 and shi 1995 2 this property has been regarded as the outcome of the original kiyotaki wright assumptions of indivisible money and the inventory constraint agents can only carry one object either commodity or money at a time despite simplifying the distribution of money holdings these assumptions impose the restriction that agents are not allowed to produce while they hold money

optimal fiscal and monetary policy in an economy without capital abstract this paper is concerned with the structure and time consistency of optimal fiscal and monetary policy in an economy without capital in a dynamic context optimal taxation means distributing tax distortions over time in a welfare maximizing way for a barter economy our main finding is that with debt commitments of sufficiently rich maturity structure an optimal policy if one exists is time consistent in a monetary economy the idea of optimal taxation must be broadened to include an inflation tax and we find that time consistency does not carry over an optimal inflation tax requires commitment by rules in a sense that has no counterpart in the dynamic theory of ordinary excise taxes the reason time consistency fails in a monetary economy is that nominal assets should from a welfare maximizing point of view always be taxed away via an immediate inflation in a kind of capital levy this emerges as a new possibility when money is introduced into an economy without capital

joint pricing and inventory control for non instantaneous deteriorating items with partial backlogging and time and price dependent demand abstract in this paper a joint pricing and inventory control for non instantaneous deteriorating items is developed we adopt a price and time dependent demand function shortages is allowed and partially backlogged the major objective is to determine the optimal selling price the optimal replenishment schedule and the optimal order quantity simultaneously such that the total profit is maximized we first show that for any given selling price optimal replenishment schedule exists and unique then we show that the total profit is a concave function of price next we present a simple algorithm to find the optimal solution finally we solve a numerical example to illustrate the solution procedure and the algorithm

a century of evolution from harris s basic lot size model survey and research agenda abstract determining the economic lot size has always represented one of the most important issues in production planning this problem has long attracted the attention of researchers and several models have been developed to meet requirements at minimum cost in this paper we explore and discuss the evolution of these models during one hundred years of history starting from the basic model developed by harris in 1913 up to today following harris s work a number of researchers have devised extensions that incorporate additional considerations the evolution of eoq theory strongly reflects the development of industrial systems over the past century here we outline all the research areas faced in the past by conducting a holistic analysis of 219 selected journal papers and trying to give a comprehensive view of past work on the eoq problem finally a new research agenda is proposed and discussed

what would yale do if it were taxable corrected january 2016 the distinctive financial goals and constraints of ultra high net worth individuals together with their aggregate growth in assets have led to the emergence of new institutional investing which includes the best practices from institutional investors but also incorporates the critical element of tax management the authors design new institutional asset allocations that incorporate traditional investment metrics in a tax aware setting specifically they show how risk and after tax returns need to be combined from inception when seeking an optimal after tax asset allocation diversification is especially important for taxable investors because low asset class correlations can facilitate the inclusion of attractive but tax inefficient asset classes in a tax aware allocation

on an eoq model for perishable items under stock dependent selling rate and time dependent partial backlogging by dye and ouyang in 2005 dye and ouyang proposed an eoq model for perishable items under stock dependent selling rate and time dependent partial backlogging and then established the unique optimal solution to the problem when building up inventory is not profitable however they did not provide the optimal solution to the problem when building up inventory is profitable in this note we establish an appropriate model in which building up inventory is profitable and then provide an algorithm to find the optimal solution to the problem a numerical example is used to illustrate the proposed model

a comparison between two pricing and lot sizing models with partial backlogging and deteriorated items abstract recently abad 2003 optimal pricing and lot sizing under conditions of perishability finite production and partial backordering and lost sale european journal of operational research 144 677 685 studied the pricing and lot sizing problem for a perishable good under finite production exponential decay partial backordering and lost sale in this article we extend his model by adding not only the backlogging cost but also the cost of lost goodwill we then analytically compare the net profits per unit time between abad s 2003 model and goyal and giri s 2003 the production inventory problem of a product with time varying demand production and deterioration rates european journal of operational research 147 549 557 model in abad s model the cycle starts with an instant production to accumulate stocks then stops production to use up stocks and finally restarts production to meet the unsatisfied demands by contrast in goyal and giri s model the cycle begins with a period of shortages then starts production until accumulated inventory reaches certain level and finally stops production and uses up inventory our theoretical results show that there is no dominant one between these two models furthermore we provide certain conditions under which one model has more net profit per unit time than the other finally we give several numerical examples to illustrate the results

the deterministic eoq and epq with partial backordering at a rate that is linearly dependent on the time to delivery abstract our original models for the eoq and epq with partial backordering assumed that the backordering rate is a constant in this paper we extend those models to allow to increase linearly as the time until delivery decreases we show how those previous models can be adapted to find the optimal decision variable values for this new assumption and develop for each model type a condition that the initial value of must meet for partial backordering to be optimal

perishable inventory theory a review this paper reviews the relevant literature on the problem of determining suitable ordering policies for both fixed life perishable inventory and inventory subject to continuous exponential decay we consider both deterministic and stochastic demand for single and multiple products both optimal and sub optimal order policies are discussed in addition a brief review of the application of these models to blood bank management is included the review concludes with a discussion of some of the interesting open research questions in the area

analysis of an inventory system with exponential partial backordering abstract in this paper we study an inventory model with partial backlogging where unsatisfied demand is partially backlogged according to an exponential function in this model the total cost is the sum of the order cost the holding cost the backorder cost which includes a fixed cost and a cost proportional to the length of time for which the backorder exists and the cost of lost sales a general approach for finding the optimal policy is developed numerical examples are used to illustrate how the approach works

having your cake and eating it too the before and after tax efficiencies of an extended equity mandate this article shows that extended mandates are especially effective for investors subject to taxes not only is the portfolio more efficiently positioned from a before tax perspective but it also offers significant after tax benefits from both increased loss harvesting and tax arbitrage between tax rates on long and short positions

advertising strategies for new product diffusion in emerging markets propositions and analysis abstract we develop advertising strategies for a firm which has a new product for which demand exists in an emerging market however the primary channels for distribution of the firm s product do not exist because either the market has not been opened up or the firm has not entered the market therefore the consumers use the secondary channels in other markets the current research seeks to answer questions such as i is it beneficial to advertise for the product before the market opens ii what should be the difference in advertising before and after the market opens iii what is the effect of various parameters such as the likelihood of product adoption for the primary and secondary channels market potential and coefficient of innovation and imitation on the optimal advertising policies the above problem is relevant for the situation faced by japanese electronics goods manufacturers before they entered the indian market or a company which has regional presence in one part of a country say urban and gets access to another part later e g rural the problem is modeled as an optimal control problem relevant propositions are developed for optimal normative advertising policy numerical examples are provided to illustrate key policy results

an optimal r q policy in a stochastic inventory system with all units quantity discount and limited sharable resource abstract this paper is concerned with the single item inventory system with resource constraint and all units quantity discount under continuous review where demand is stochastic and discrete in most actual inventory systems the resource available for inventory management is limited and the system is able to confront the resource shortage by charging more costs considering the resource constraint as a soft constraint beside a quantity discount opportunity makes the model more practical an optimization problem is formulated for finding an optimal r q policy for the problem in which the per unit resource usage depends on unit purchasing price the properties of the cost function are investigated and then an algorithm based on a one dimensional search procedure is proposed for finding an optimal r q policy which minimizes the expected system costs and converges to a global optimum based on the properties of the partially conditioned cost functions the presented algorithm is modified such that its search path to optimal policy is changed experimental results show that the performance of the modified version of the presented algorithm is much better than the original algorithm in various environments of test problems

joint inventory allocation and pricing decisions for perishable products abstract we jointly determine the price and the inventory allocation for a perishable product with a predetermined lifetime we assume that the price of the product increases as the time when it perishes approaches as in the airline industry demand for the product is price sensitive to maximize the expected revenue we developed a discrete time dynamic programming model to obtain the optimal prices and the optimal inventory allocations for the product with a two period lifetime we then proposed three heuristics when the lifetime is longer than two periods the computational results showed that the expected revenues from the proposed heuristics were very close to that of the optimal solution we extended these results to i the case where the price for the product consistently decreases and ii the case where the price for the product first increases and later decreases

money barter and costly information acquisition abstract endogenous information structure is analyzed in a search model of production and exchange under qualitative uncertainty by allowing agents to invest in an inspection technology at a fixed cost where incurring a higher cost permits quality to be recognized with higher probability in any equilibria where agents acquire information some bad commodities are always produced the information acquisition promotes production and exchange of good commodities as the information problem becomes severe money can improve welfare by economizing on information costs in the optimal monetary equilibrium agents adopt trading strategies which contribute to the saving of information costs

integrating deterioration and lifetime constraints in production and supply chain planning a survey abstract items with short lifetimes that are subject to deterioration are important in the business world research has a long tradition in integrating deterioration and value loss effects into mathematical models for inventory planning and control where such effects are understood as a general loss or shrinkage of inventory however there has been little work in the modeling of lifetime restrictions of items to prevent wastage and disposals especially in a dynamic planning context globalization and other trends extend the consideration of single companies to whole supply chains implying increased coordination and information needs this is important as planning decisions impact lead times and thus the quality of items in the whole supply chain products that exceed their useful lifetime can impose high costs due to inventory loss or the need to rework them this implies increased utilization of scarce resources e g machine time metals and or energy thereby increasing co 2 levels we survey the state of the art regarding depreciation effects and the modeling of lifetime constraints as well as a classification of models following business planning functions of the value chain a critical evaluation of approaches and their limitations is provided highlighting directions for future research

inventory models with ramp type demand rate partial backlogging and weibull deterioration rate in this paper an inventory model with general ramp type demand rate time dependent weibull deterioration rate and partial backlogging of unsatisfied demand is considered the model is studied under the following different replenishment policies a starting with no shortages and b starting with shortages the model is fairly general as the demand rate up to the time point of its stabilization is a general function of time the backlogging rate is any non increasing function of the waiting time up to the next replenishment the optimal replenishment policy for the model is derived for both the above mentioned policies

capacity allocation and scheduling in supply chains we consider a multiple product supply chain where a manufacturer receives orders from several distributors if the orders cannot all be met from available production capacity then the manufacturer allocates that capacity and a set of resubmittable orders among the distributors the distributors may share their allocated capacity among themselves before submitting revised orders finally the manufacturer schedules the revised orders to minimize its cost we consider three practical coordination issues first we estimate the benefit to the manufacturer from considering scheduling costs and constraints in making capacity and order allocation decisions second we estimate the additional profit that the distributors achieve when they share their allocated capacity third we estimate the value of coordination between the manufacturer and the distributors our work is among the first to consider all three issues simultaneously we model scheduling costs and constraints within the manufacturer s capacity allocation problem we model the distributors capacity sharing problem as a cooperative game that has properties that are unique within cooperative game theory finally we develop optimal algorithms for all the models defined by the three coordination issues our exact evaluation of decisions about the appropriate coordination level improves managers ability to make those decisions

review of inventory systems with deterioration since 2001 abstract this paper presents an up to date review of the advances made in the field of inventory control of perishable items deteriorating inventory the last extensive review on this topic dates back to 2001 goyal s k and giri b c recent trends in modeling of deteriorating inventory european journal of operational research 134 1 16 since then over two hundred articles on this subject have been published in the major journals on inventory control indicating the need for a new review we use the classification of goyal and giri based on shelf life characteristics and demand characteristics contributions are highlighted by discussing main system characteristics including price discounts backordering or lost sales single or multiple items one or two warehouses single or multi echelon average cost or discounted cash flow and payment delay

monetary economics a review essay in this essay i define money to be whatever objects serve as generally acceptable media of exchange and i define monetary economics to be the study of the causes and economic consequences of the monetization of exchange that is of the use of media of exchange these definitions lead me to specify the distinctive objectives of monetary economics to be to understand 1 the monetization of exchange and its relation to the technologies of production and of exchange 2 the form that money takes and especially the viability of fiat money 3 the determination and significance of the real value of units of money and 4 the relation between the nominal quantity of money and aggregate economic activity the essay tries to acquaint the reader with the contents of the recently published handbook of monetary economic as they relate to these objectives of monetary economics and offer some critical thoughts on selected unsettled issues in monetary economics that my reading of the handbook suggested this abstract was borrowed from another version of this item

a joint optimal pricing rebate value and lot sizing model delayed incentives in the form of mail in cash rebates are very popular among manufacturers and more recently among retailers one of the main advantages of rebates is that while they increase demand a small proportion of consumers redeem them in this paper we formulate and solve models for jointly determining the optimal price rebate face value and the optimal order quantity for a price and rebate sensitive deterministic demand the models show that under realistic conditions offering rebates can have significant pricing and inventory policy implications and can lead to a significant increase in profit

optimal price and order size under partial backordering incorporating shortage backorder and lost sale costs abstract in this paper we consider the pricing and lot sizing problem for a product subject to general rate of deterioration and partial backordering we use impatience functions to model backlogging of demand we show that even when lost sale and backorder costs are present the problem is well posed in the reduced space we provide an iterative procedure for solving the overall problem we describe structural properties of the solution for the new model and comment on the recent work incorporating backorder cost we illustrate the solution procedure for the new model with examples

determining optimal selling price and lot size with a varying rate of deterioration and exponential partial backlogging in this paper a deterministic inventory model for deteriorating items with price dependent demand is developed the demand and deterioration rates are continuous and differentiable function of price and time respectively in addition we allow for shortages and the unsatisfied demand is partially backlogged at a negative exponential rate with the waiting time under these assumptions for any given selling price we first develop the criterion for the optimal solution for the replenishment schedule and prove that the optimal replenishment policy not only exists but also is unique if the criterion is not satisfied the inventory system should not be operated next we show that the total profit per unit time is a concave function of price when the replenishment schedule is given we then provide a simple algorithm to find the optimal selling price and replenishment schedule for the proposed model finally we use numerical examples to illustrate the algorithm

the welfare cost of inflation in a cash in advance economy with costly credit the paper presents a modification of the lucas stokey 1983 cash in advance economy in which the representative consumer decides based on relative prices which goods to buy with cash and which with costly credit an explicit baumol 1952 condition emerges that guides this consumer choice deriving and estimating a closed form welfare cost function in an example economy the paper shows that the welfare cost of inflation depends on the margins of substitution the consumer avoids inflation through costly credit and faces higher welfare costs of inflation than in standard cash in advance economies

an approximation to the continuous review inventory model with perishable items and lead times a continuous review perishable inventory model based on approximations to the expected outdating the expected shortage quantity and the expected inventory level is developed to determine a best q r ordering policy under a positive order leadtime when the total expected average cost per unit time is minimized the approximation method is simple and verified by a comparison with the weiss model the results reveal that the mean absolute deviation from the optimal total expected average cost per unit time is only 0 58 this paper also compares the proposed model to the conventional model with no perishability a value is given to the item lifetime indicating when an approximate answer approaches closely to the conventional ordering policy finally a simulation model written in simscript ii 5 is used to validate the approximate results

competitive strategies for two firms with asymmetric production cost structures we model joint production marketing strategies for two firms with asymmetric production cost structures in competition the first firm called the production smoother faces a convex production cost and a linear inventory holding cost the second firm called the order taker faces a linear production cost and holds no inventory each firm is assumed to vary continuously over time both its production rate and its price in view of an unstable surge pattern of demand the underlying theoretical motivation is to investigate the temporal nature of the equilibrium policies of two competing firms one operating at or near capacity the production smoother and one operating significantly below capacity the order taker we characterize and compare the equilibrium strategies of the two competing firms among our results we show that if the duopolistic production smoother finds it optimal to hold inventory then he will begin the season by building up inventory continue by drawing down inventory until i

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

an integrated production inventory model with imperfect production processes and weibull distribution deterioration under inflation abstract this study develops an integrated production and inventory model from the perspectives of both the manufacturer and the retailer the model assumes a varying rate of deterioration partial backordering inflation imperfect production processes and multiple deliveries the elapsed time until the production process shift is assumed to be arbitrarily distributed the discounted cash flow and classical optimization technique are used to derive the optimal solution a numerical example including the sensitivity analysis is given to validate the results of the production inventory model the integrated decision results in lower optimal joint cost compared with an independent decision by the manufacturer and the retailer

the tax benefits of separating alpha from beta long only active investment strategies have an inherent flaw investors pay capital gains taxes on market related gains as well as on the alpha created by separating alpha and beta taxes can be r

commodity money under private information abstract private information is introduced into the kiyotaki wright model of commodity money in terms of qualitative uncertainty concerning the good which would be the unique medium of exchange under complete information producers are allowed to produce high or low quality versions of that good and people may not always recognize its quality it is shown that commodities that suffer from qualitative uncertainty may still be used as the medium of exchange when the private information problem is not too severe this is so despite the fact that in some equilibria there is necessarily some low quality commodity money in circulation when the information problem is so severe that the good of uncertain quality cannot be the unique money there can exist an equilibrium with dual commodity monies of which one is the good subject to qualitative uncertainty

pricing and manufacturing decisions when demand is a function of prices in multiple periods in most deterministic manufacturing decision models demand is either known or induced by pricing decisions in the period that the demand is experienced however in more realistic market scenarios consumers make purchase decisions with respect to price not only in the current period but also in past and future periods we model a joint manufacturing pricing decision problem accounting for that portion of demand realized in each period that is induced by the interaction of pricing decisions in the current period and in previous periods we formulate a mathematical programming model and develop solution techniques we identify structural properties of our models and develop closed form solutions and effective heuristics for various special cases of our models finally we conduct extensive computational experiments to quantify the effectiveness of our heuristics and to develop managerial insights

tax management loss harvesting and hifo accounting virtually all companies and individuals are faced with the management of taxable assets to manage these assets efficiently investors need to be aware of the impact of taxes on investment returns in the study we report in this article we quantified the benefits of loss harvesting and highest in first out hifo accounting by using monte carlo simulations and investigated the robustness of these strategies in various markets and with various cash flows and tax rates we concluded that a market with high stock specific risk low average return and high dividend yield provides more opportunities to harvest losses in addition a steady stream of contributions refreshes a portfolio and allows the benefits of loss harvesting to remain strong over time conversely withdrawals reduce the advantages of realizing losses our findings show that no matter what market environment occurs in the future managing a portfolio in a tax efficient manner gives substantially better after tax performance than a simple i

joint pricing and ordering policy for two echelon imperfect production inventory model with two cycles abstract this study deals with an imperfect epq economic production quantity price dependent inventory model over two types of cycles in the first cycle the retailer sells only good product with actual price and in the second he sells the products with a discount price in the production run time the non conforming items are produced at a random rate and they are reworked after the regular production run time and the reworked items are almost perfect as good as original quality items the retailer starts the second cycle when a certain percent of good items are left to him after the completion of regular production the retailer continues simultaneously two cycles up to which both types of the products are available to him now our objective is to find out optimal ordering lot size and optimal price for which the profit of the integrated model is maximum also we check the best strategy of retailer for the time of starting second cycle a numerical example is provided to illustrate the behavior and application of the model

a comparison among various partial backlogging inventory lot size models for deteriorating items on the basis of maximum profit abstract during the past few years there are many researches that deal with different inventory shortage models for deteriorating items and then use minimizing cost as objective to find the optimal replenishment policy over a finite planning horizon in contrast to the other articles we here use maximizing profit as the objective to find the optimal replenishment policy we consider the case of partial backlogging for deteriorating items with four different inventory models not only the opportunity cost due to lost sale but also the purchase cost is taken into account we then make an appropriate comparison among these four alternatives finally some numerical examples are provided

modeling customer impatience in a newsboy problem with time sensitive shortages abstract customers across all stages of the supply chain often respond negatively to inventory shortages one approach to modeling customer responses to shortages in the inventory control literature is time dependent partial backlogging partial backlogging refers to the case in which a customer will backorder shortages with some probability or will otherwise solicit the supplier s competitors to fulfill outstanding shortages if the backorder rate i e the probability that a customer elects to backorder shortages is assumed to be dependent on the supplier s backorder replenishment lead time then shortages are said to be represented as time dependent partial backlogging this paper explores various backorder rate functions in a single period stochastic inventory problem in an effort to characterize a diversity of customer responses to shortages we use concepts from utility theory to formally classify customers in terms of their willingness to wait for the supplier to replenish shortages under mild assumptions we verify the existence of a unique optimal solution that corresponds to each customer type sensitivity analysis experiments are conducted in order to compare the optimal actions associated with each customer type under a variety of conditions additionally we introduce the notion of expected value of customer patience information evcpi and then conduct additional sensitivity analyses to determine the most and least opportune conditions for distinguishing between customer behaviors

deterministic inventory model for deteriorating items with capacity constraint and time proportional backlogging rate in this paper a deterministic inventory model for deteriorating items with two warehouses is developed a rented warehouse is used when the ordering quantity exceeds the limited capacity of the owned warehouse and it is assumed that deterioration rates of items in the two warehouses may be different in addition we allow for shortages in the owned warehouse and assume that the backlogging demand rate is dependent on the duration of the stockout we obtain the condition when to rent the warehouse and provide simple solution procedures for finding the maximum total profit per unit time further we use a numerical example to illustrate the model and conclude the paper with suggestions for possible future research

an inventory model with partial backordering and unit backorder cost linearly increasing with the waiting time as the implementation of jit practice becomes increasingly popular each echelon in a supply chain tends to carry fewer inventories and thus the whole supply chain is made more vulnerable to lost sales and or backorders the purpose of this paper is to recast the inventory model to be more relevant to current situations where the penalty cost for a shortage occurrence at a downstream stage in a supply chain is continually transmitted to the upstream stages the supplier in this case at the upstream of the supply chain is responsible for all the downstream shortages due to the chain reaction of its backlog the current paper proposes a model in which the backorder cost per unit time is a linearly increasing function of shortage time and it claims that the optimal policy for the supplier is setting the optimal shortage time per inventory cycle to minimize its total relevant cost in a jit environment

optimal lot size for a production inventory system with partial backlogging and mixture of dispatching policies abstract in this paper we study a production inventory model for a single product where shortages are partially backlogged both the backorder cost and the lost sale cost depend on a fixed cost and a cost proportional to the shortage time we assume a mixture between the dispatching policies known as lifo last in first out and fifo first in first out in the discipline of service to fill the backlogged demand by using a sequential optimization procedure we determine in a closed form the optimal production policies and the optimal profit for all the possible cases obtained from the developed model we show how this new model generalizes several inventory models proposed in the literature finally numerical results are presented to analyze the sensitivity of the optimal policies with respect to changes in some parameters of the system

an inventory model with generalized type demand deterioration and backorder rates abstract this study is motivated by the paper of skouri et al skouri konstantaras papachristos ganas european journal of operational research 192 1 2009 79 92 we extend their inventory model from ramp type demand rate and weibull deterioration rate to arbitrary demand rate and arbitrary deterioration rate in the consideration of partial backorder we demonstrate that the optimal solution is actually independent of demand that is for a finite time horizon any attempt at tackling targeted inventory models under ramp type or any other types of the demand becomes redundant our analytical approach dramatically simplifies the solution procedure

replenish up to inventory control policy with random replenishment intervals abstract the multi period inventory problems have been studied under two main assumptions continuous review assumption where an order can be made at any time depending on inventory position and periodic review assumption where an order can be initiated only at discrete time epochs in this study we analyze a multi period inventory problem that falls under neither of these two assumptions in the case we consider there are periodic replenishments but the replenishment intervals are taken to be i i d random variables this setting represents the real life cases where a supplier visits a retailer with random inter arrival times and the retailer replenishes his inventories based on a replenish up to level inventory control policy we also assume that only a certain fraction of unmet demand is backordered and the rest of it is lost in this setting under general distribution between replenishment epochs we show the concavity of the expected profit function and give the condition that must hold for the optimal replenish up to level we also present the specific solutions and analysis under two different distributions namely uniform and exponential distributions together with some numerical examples

an empirical evaluation of tax loss harvesting alpha advances in financial technology have made tax loss harvesting more feasible for retail investors than such strategies were in the past we evaluated the magnitude of this tax alpha with the use

anticipated inflation and the capital stock in a cash in advance economy abstract an economy is constructed in which the steady state capital stock is inversely related to the rate of inflation as a result that is directly opposite the usual conclusion

monetary policy and bank regulations in an economy with financial innovations this is a study of financial innovations and moves towards the cashless society in a general equilibrium cash in advance model it is assumed that a subset of goods cash goods and check goods

joint pricing and replenishment policy for deteriorating inventory with declining market abstract this study deals with a deteriorating inventory model where demand decreases linearly with time and cost of items planning horizon is assumed to be finite the replenishment cycles are constant and shortages are partially back ordered the net profit maximizing ordering policy and price are determined for different degree of partial back ordering the reduction in revenue resulted from lost sale is expressed in the lost sale shortage penalty in the total cost formulation a solution method based on nonlinear programming code and the hessian matrix guarantees global optimality of the solution a numerical example is provided to illustrate the theory

joint pricing and inventory policies for make to stock products with deterministic price sensitive demand abstract in this paper we focus on a firm selling a single make to stock product to price sensitive end customers we develop an integrated operations marketing model that can help determine the relevant profit maximizing decision variable values for two pricing policies that the firm might follow price as a decision variable which is advocated by academicians and mark up pricing used by most practitioners we first consider an eoq based model with price and order quantity as independent decision variables we then develop an analogous model where price is a mark up over operating costs per unit and order quantity becomes the sole decision variable we are able to ascertain the optimal decision variable values for each model for log linear and linear demand functions we prove that for such profit maximizing models the optimal batch size is not necessarily monotone increasing in set up cost interestingly our numerical analytical evidence suggests that from a profit perspective it is better for managers to be aggressive on price rather than reducing price too much especially for highly price sensitive and non linear demand moreover we establish that in general the profit penalty for not including inventory costs in determining the optimal batch size or ignoring the batch size optimization issue in a mark up price model is not significant only when the set up cost is quite high and or the firm faces non linear demand from highly price sensitive end consumers does it become crucial for managers to determine the exact optimal batch size and base the mark up price on the entire unit operating cost not only the unit variable production cost

an inventory model for perishable items in a lot size system with quantity discounts abstract an inventory model continuous in units and time is developed for perishable items in a lot size system that allows partially backlogging and partially lost saling the model is developed under deterministic demand instantaneous delivery with quantity discounts and any well behaved probability distribution for the time to perishables an example is given to illustrate the model

the impact of dynamic pricing on the economic order decision this paper analyzes the impact of dynamic pricing on the single product economic order decision of a monopolist retailer items are procured from an external supplier according to the economic order quantity eoq model and are sold to customers on a single market without competition following the simple monopolist pricing problem coordinated decision making of optimal pricing and ordering is influenced by operating costs including ordering and inventory holding costs and the demand rate obtained from a price response function the retailer is allowed to vary the selling price either in a fixed number of discrete points in time or continuously while constant and continuous pricing have received much attention in the literature problems with a limited number of price changes are rather rare this paper illustrates the benefit of dynamically changing prices to achieve operational efficiency in the eoq model that is to trigger high demand rates when inventories are high we provide structural properties of the optimal time instants when the price should be changed taking into account costs for changes in price it provides numerical guidance on number timing and size of price changes during an order cycle numerical examples show that the benefits of dynamic pricing in an eoq framework can be achieved with only a few price changes and that products being unprofitable under static pricing may become profitable under dynamic pricing

a survey of deterministic models for the eoq and epq with partial backordering models for the basic deterministic eoq or epq problem with partial backordering or backlogging make all the assumptions of the classic eoq or epq model with full backordering except that only a fraction of the demand during the stockout period is backordered in this survey we review deterministic models that have been developed over the past 40 years that address the basic models and extensions that add other considerations such as pricing perishable or deteriorating inventory time varying or stock dependent demand quantity discounts or multiple warehouses

inventory of differential items selling from two shops under a single management with periodically increasing demand over a finite time horizon abstract inventories of differential items including the defective ones purchased produced in a lot and sold from two shops primary and secondary shops under a single management are considered here over a finite time horizon a primary shop receives the differential units in a lot but sells only the non defective ones whose demand periodically increases with time and decreases during the shortage period in such a way that it comes back to the initial value at the beginning of the next cycle hence in this shop shortages are allowed and fully backlogged moreover at the beginning of the next cycle the retailer purchases purely non defective units at a higher price to meet up the shortage amount along with the usual lot of differential units for regular sale the defective units identified at the time of selling at the primary shop are continuously transferred to the adjacent secondary shop from which the defective ones are sold at a reduced price after some rework normally the price of a defective item is fixed depending upon the quantum of its defect and people go for these items if they are cheap hence demand for these units is dependent on the selling price which is again inversely proportional to the rate of defectiveness there may be five scenarios for dealing with defective units depending upon the coincidence of the time periods at two shops for all scenarios problems have been mathematically formulated and solved by the use of both parametric study and a gradient based non linear optimisation method the models are illustrated with the help of numerical examples

advanced supply chain planning with mixtures of backorders lost sales and lost contract abstract this paper investigates a supply chain system in which a supplier prepares for the selling season by building stock levels prior to the beginning of the season and shortages realized at the beginning of the season are represented as mixtures of backorders and lost sales backlogged items are replenished as soon as possible through an emergency procurement as opposed to waiting until the next scheduled delivery as in many continuous review scenarios and the backorder rate is modeled as a piecewise linear function of the magnitude of the shortage the often intangible cost associated with lost sales and customer goodwill is also quantified in particular the buyer and supplier are engaged in a contractual agreement and the loss of customer goodwill from the supplier s perspective is represented as the expected cost associated with violating the conditions of the contract the likelihood of contract cancellation is also represented as a function of the magnitude of shortage the optimal solution is derived in closed form for the case of exponential demand distribution and an example problem is illustrated with numerical data in order to demonstrate calculation of the optimal solution and corresponding sensitivity analysis for demand distributions in which the solution cannot be expressed in closed form

adaptive ordering and pricing for perishable products we consider the combined problem of pricing and ordering for a perishable product with unknown demand distribution and censored demand observations resulting from lost sales faced by a monopolistic retailer we develop an adaptive pricing and ordering policy with the asymptotic property that the average realized profit per period converges with probability one to the optimal value under complete information on the distribution the pricing mechanism is modeled as a multiarmed bandit problem while the order quantity decision made after the price level is established is based on a stochastic approximation procedure with multiplicative updates

a search theoretic approach to monetary economics the essential function of money is its role as a medium of exchange the authors formalize this idea using a search theoretic equilibrium model of the exchange process that captures the double coincidence of wants problem with pure barter one advantage of the framework described here is that it is very tractable the authors also show that the model can be used to addre ss some substantive issues in monetary economics including the potenti al welfare enhancing role of money the interaction between specializat ion and monetary exchange and the possibility of equilibria with multip le fiat currencies copyright 1993 by american economic association

the deterministic eoq with partial backordering a new approach previous authors have shown that if demand that cannot be filled from stock is partially backordered then using the full backordering model or assuming that all stockouts will result in lost sales can lead to substantial increases in cost relative to using a model that specifically recognizes the percentage of the stockouts that will be backordered the models that these authors developed resulted in procedures or equations that are relatively difficult to use in this paper we take a different approach to modeling the deterministic eoq with partial backordering that results in equations that are more like the comparable equations for the basic eoq and its full backordering extension

optimal dynamic pricing and ordering decisions for perishable products abstract in this paper we determine the order quantity and the prices for a perishable product with a multiple period lifetime demands for products of different ages are dependent on the prices of mutually substitutable products the problem for a product with lifetime of two periods is first analyzed and the stochastic dynamic programming model is developed given the inventory level for the old product product of age 2 the expected profit is a concave function of the order quantity the price of the new product product of age 1 and the discounted price of the old product product of age 2 the computational results show that the total profit significantly increases when demand transfers between products of different ages are considered for a product with lifetime of longer than two periods a heuristic based on the optimal solution for a single period problem is proposed for a multiple period problem

tax managed factor strategies we examine the tax efficiency of an indexing strategy and six factor tilts between june 1995 and march 2018 average value added by tax management exceeded 1 50 per year at a 10 year horizon for

retailer s optimal pricing and lot sizing policies for deteriorating items with partial backlogging pricing is a major strategy for a retailer to obtain its maximum profit therefore in this paper we establish an economic order quantity model for a retailer to determine its optimal selling price replenishment number and replenishment schedule with partial backlogging we first prove that the optimal replenishment schedule not only exists but also is unique for any given selling price next we show that the total profit is a concave function of p when the replenishment number and schedule are given we then provide a simple algorithm to find the optimal selling price replenishment number and replenishment timing for the proposed model finally we use a couple of numerical examples to illustrate the algorithm

an inventory model with deteriorating items quantity discount pricing and time dependent partial backlogging abstract wee international journal of production economics 59 1999 511 in his interesting paper presented a deterministic inventory model with the following characteristics quantity discount schemes for the unit cost partial backlogging at a fixed rate deterioration of stock in time and demand rate being a linear function of the selling price in this article we generalize the work of wee 1999 more specifically we consider a model where the demand rate is a convex decreasing function of the selling price and the backlogging rate is a time dependent function which ensures that the rate of backlogged demand increases as the waiting time to the following replenishment point decreases

a further exploration in the theory of exchange rate regimes in an interesting paper in this journal elhanan helpman 1981 develops a simple two country model to compare the welfare levels that are achieved under different exchange rate regimes in a world characterized by perfect foresight his basic finding is that equilibrium consumption allocations and hence welfare levels are identical under a floating exchange rate system and a one sided peg fixed exchange rate regime this result is due to helpman s assumption that output is determined exogenously which allows a separation of the real and monetary sides of the economy the purpose of this paper is to extend helpman s model by making two alterations in his setup 1 to allow production to be endogenously determined as a function of labor force participation and 2 to allow welfare levels to be dependent on labor service as well as on consumption the main conclusion then obtained is that a country may achieve a higher welfare level under a flexible exchange rate regime than under a fixed exchange rate regime since it is able to choose an optimal rate of inflation or currency depreciation

armen alchian s contribution to macroeconomics i introduction this essay examines alchian s contribution to the theory and practice of macroeconomics we have the task of reviewing alchian s contributions in an area that represents only a tiny fraction of his body of work citations to his work on the theory of the firm greatly outnumber those on money and inflation nevertheless we find that many of the major developments in macroeconomics in the last two decades follow paths that were pointed out in the late 1950s and early 1960s by armen alchian much of it in collaboration with reuben kessel alchian s ideas about macroeconomics were developed in a fertile environment at ucla in conversations with colleagues such as karl brunner and jack hirshleifer as well as with graduate students such as allan meltzer and rachael and ted balbach a signature of alchian s work was his great ability to clarify the issues he was careful to distinguish the effects of money versus real shocks of anticipated versus unanticipated inflation and to work through the impact of an event to the general equilibrium consequences he understood that real world problems such as incomplete information might explain apparently noneconomic behavior but unlike many macroeconomists of that time he did not abandon microeconomic principles when explaining nominal real interactions alchian s views were a clear contrast to those of prominent macroeconomists of the day who argued that aggregate monetary policies could not be used to stabilize the price level at full employment because of asymmetric rigidities in markets that prevented the downward adjustment of any nominal price as part of the process of adjusting relative prices 1 the conventional wisdom of the day led to policies that ultimately caused two decades of accelerating and costly inflation both the rational expectations revolution and developments in modeling the microfoundations of business cycles were a reaction to this experience and to the apparent failure of standard macroeconomic analysis alchian s 1970 work on the effect of private information was one of the original articles in this microfoundation literature although he used a narrative approach rather than the highly structured mathematical models available to researchers today alchian was more than two decades ahead of the real business cycle economists in asking researchers to explore economic explanations fully before adopting explanations based on market failure money illusion and irrational behavior this paper is organized in four parts the first part describes alchian s work involving the fundamental role of money in society king and plosser 1986 93 wrote but in the explosion of formal modeling of monetary economies in the postwar period brunner and meltzer 1971 and alchian 1977 stand nearly alone in stressing the idea that monetary arrangements economize on the information production that would otherwise be necessary to mitigate problems of moral hazard in the exchange of commodities the second part discusses alchian and klein s work on the measurement of inflation this measurement problem appears to be more obvious when inflation is low and the variance of price indexes is dominated by real factors this work was generally neglected at the time it was written perhaps because inflation accelerated so rapidly that the real factors became less important now that inflation has declined to moderate levels the measurement problems are resurfacing the third part of the paper documents alchian s insight into the problems and intellectual developments that followed the erratic inflation policies of the u s government in the 1960s and 1970s in a 1962 journal of political economy article he and reuben kessel set forth a description of the events that occur as an economy shifts from one steady state inflation regime to another this work revealed an understanding of the importance of credibility for the policymaker that was missing from much of the writing about macro policymaking in the subsequent three decades

optimal policy for an inventory system with backlogging and all units discounts application to the composite lot size model this paper examines an inventory model with full backlogging and all units quantity discounts the practical scenario of a salesperson offering compensation to a client so as not to lose the sale is considered the cost of a backorder thus includes both a fixed cost and a further cost which is proportional to the length of time the said backorder exists a first algorithm is developed to determine the optimal policy while some extensions to this algorithm are obtained that include additional conditions on the model in particular the well known composite lot size model developed by tersine is solved incorporating a new stockout cost and a new all units discount numerical examples are provided to illustrate the application of the algorithms

money and information this paper investigates the role of money in markets in which producers have private information about the quality of the goods they supply when the fraction of high quality producers in the economy is given money promotes the production of high quality goods which improves the quality mix and welfare unambiguously when this fraction is endogenous however we find that money can decrease welfare relative to the barter equilibrium the origin of this inefficiency is that money provides consumption insurance to low quality producers which can result in a higher fraction of low quality producers in the monetary equilibrium finally we find that most often agents acquire more costly information in the monetary equilibrium than in the barter equilibrium consequently money is welfare enhancing because it promotes useful production and exchange but not because it saves information costs

optimal pricing and lot sizing under conditions of perishability and partial backordering we formulate a generalized model of dynamic pricing and lot sizing by a reseller who sells a perishable good we assume that when it is economic to backlog demand the reseller can plan for periods of shortage during which demand can be partially backordered when the good is highly perishable the reseller may need to backlog demand in order to market the good at a reasonable price we present a simple solution procedure for solving the optimization problem the procedure entails solving first a single nonlinear equation and then if required two nonlinear equations

on a finite horizon production lot size inventory model for deteriorating items an optimal solution abstract a generalized production lot size inventory model for deteriorating items over a finite planning horizon is considered the demand production and deteriorating rates are assumed to be known and continuous functions of time shortages are allowed and completely backlogged the conditions under which the system total cost attains its unique global minimum are derived an example which illustrate the applicability of theoretical results is also introduced

dynamic pricing and ordering decisions by a monopolist this paper considers the relationship between pricing and ordering decisions for a monopolistic retailer facing a known demand function where over the inventory cycle the product may exhibit i physical decay or deterioration of inventory called wastage and ii decrease in market value called value drop associated with each unit of inventory on hand the retailer is allowed to continuously vary the selling price of the product over the cycle we introduce a notion of instantaneous margin and use it to derive profit maximizing conditions for the retailer the model explains the markdown of retail goods subject to decay it also provides guidance in determining when price changes during the cycle are worthwhile due to product aging how often such changes should be made and how such changes affect ordering intervals and quantities