the new electricity market of singapore regulatory framework market power and competition abstract this study examines whether the new electricity market of singapore nems is functioning at a workable level of competition the generation market of the nems appears highly concentrated by a four firm concentration ratio or the herfindahl hirschman index however other measures of market power present that the nems is working at close to a competitive market first there seems to be a number of effective competitors in the market second supply margin assessment and residual supply index support that the market is competitive though there are some possibilities in which the largest generator or a few large generators jointly could still have market power third the lerner index of the nems shows that the generation market is fairly competitive and the lerner index adjusted with an industry level price elasticity of demand implies that there has not been much exercise of market power finally vesting contracts a contractual obligation of a specified quantity of electricity supply to the market have appeared to be a strong and effective tool to mitigate market power in the nems the vesting contracts are considered the force behind the lowering in the average uniform singapore electricity price and the lerner index in 2004

determining optimal lot size for a two warehouse system with deterioration and shortages using net present value abstract in this paper we develop a deterministic inventory model for deteriorating items with two warehouses by minimizing the net present value of the total cost deterioration rates of items in the two warehouses may be different in addition we allow for shortages and complete backlogging we then prove that the optimal replenishment policy not only exists but also is unique under some condition further the result reveals that the reorder interval based on the average total cost if it exists must be longer than that derived using net present value finally we use yang s h l yang european journal of operational research 157 2004 344 356 numerical example to illustrate the model and conclude the paper with suggestions for possible future research

dynamic market models in industrial organization abstract this paper surveys empirical work done on dynamic models of market performance these fall into one of two categories structural models which model how market structure and performance change in response to entry and reduced form models which describe change regardless of how it is brought about a typical example of each type of model is chosen from the literature and simulations are used to draw out the implications of the estimated coefficients both models depict the competitive process in the us economy as being extremely slow

two warehouse partial backlogging inventory models for deteriorating items under inflation abstract in many real life situations the practical experiences reveal that some but not all customers will wait for backlogged items during a shortage period such as for fashionable commodities or high tech products with short product life cycle the longer the waiting time is the smaller the backlogging rate would be according to such phenomenon taking the backlogging rate into account is necessary thus i here extend the models introduced in yang 2004 two warehouse inventory models for deteriorating items with shortages under inflation european journal of operational research 157 2 344 356 to incorporate partial backlogging and then compare the two two warehouse inventory models based on the minimum cost approach the study shows that the optimal solution not only exists but also is unique and model 2 is still less expensive to operate than model 1 if the factors of partial backlogging and inflationary effect are considered finally some numerical examples for illustration are provided and sensitivity analysis on some parameters is made

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

the intertemporal behavior of economic profits abstract the intertemporal behavior of economic profits is examined tests show that profit rates are not independent of their initial level a set of tests for the nature of the profit adjustment mechanism is proposed and a stock market based profit measure is employed despite intertemporal dependence we find evidence of profit rate adjustment patterns roughly consistent with neoclassical theory for negative profits in some but not all cases the probability of maintaining positive profits appears less than the probability of moving toward zero profits

an eoq model with partial backordering and advance payments for an evaporating item abstract in the classic economic order quantity model the purchasing cost of an order is paid at the time of its receipt in some cases retailers ask purchasers to pay all or a fraction of the purchasing cost in advance and may allow them to divide the prepayment into several equal sized parts in this paper an economic order quantity model for an evaporating item with partial backordering and partial consecutive prepayments is developed with a real case study of a gasoline station real numerical examples illustrate the proposed model and the solution method

a deterministic order level inventory model for deteriorating items with two storage facilities abstract in this paper a deterministic inventory model is developed for a single deteriorating item which is stored in two different warehouses a rented warehouse is used to store the excess units over the fixed capacity w of the own warehouse the rented warehouse is assumed to charge higher unit holding cost than the own warehouse but to offer a better preserving facility resulting in a lower rate of deterioration for the goods than the own warehouse the optimal stock level for the beginning of the period is found and the model developed is shown to agree with the order level model for non deteriorating items with a single storage facility an illustration to show the applicability of the model is also presented

a comparative analysis of intertemporal behavior of profits japan and the united states this paper first asks whether the working of market forces in japanese manufacturing industries is unique to them or similar to u s counterparts it is found that autoregressive profit equations for 376 japanese firms over 1964 82 are on average similar to those for 413 u s firms over 1964 80 the paper next asks whether the interindustry pattern of profit adjustments in japan is related to industry traits in a manner analogous to the united states in this case specific national differences between the two countries in the effects of imports industry growth and capital intensity on the profit adjustment process are found copyright 1989 by blackwell publishing ltd

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

the persistence of profits a european comparison this paper is concerned with modeling the movements in profits of firms over time at the heart of the emp irical model is a latent variables problem which arises from the fact that entry and imitation do not actually have to occur to have an ef fect on profits a solution to this problem is explored and then emp irical results are presented comparing a sample of firms from the uni ted kingdom france and west germany copyright 1988 by royal economic society

the age of electricity the age of electricity is coming driven by rapid technological change on the demand side the digitalization of many processes is leading to technologies that require electricity rather than liquid or solid fuels on the supply side renewable energy technologies provide electricity directly at falling cost electrification directly and indirectly e g using electricity to produce hydrogen fuel can aid the decarbonization of the economy strong climate policy would accelerate electrification the big question is when not if and the transition is not occurring anywhere near fast enough to meet the paris climate goals the immediate impact of the coming age of electricity is the transformation of electricity markets which need to adapt to near zero marginal costs and intermittency in the longer term the impact on fossil fuels will be radical fossil fuel prices will fall with demand and the oil and gas majors will either completely transform themselves or will harvest profits and exit

a deterministic order level inventory model for deteriorating items with two storage facilities abstract sarma 3 developed an inventory model for a single deteriorating item which is stored in two different warehouses an owned warehouse ow and a rented warehouse rw the rented warehouse is used for storing the excess units over the fixed capacity w of the ow and is assumed to offer better preserving facilities than the ow resulting in a lower rate of deterioration also the rw is assumed to charge higher holding cost than the ow in his paper sarma obtained an optimal replenishment schedule when the demand rate is constant over a fixed cycle length where the ow has to stock a specified known quantity in this paper we relax the assumptions of fixed cycle length and known quantity to be stocked in the ow further we find the optimal schedule that minimizes the total cost per unit time in a cycle for an arbitrary demand rate function where cycles are assumed to form a regenerative process we also present numerical examples

intangible capital aspects of advertising and r d expenditures twenty years have passed since economists first emphasized the intangible capital aspects of advertising according to this view consumers tend to forget brands and continuous advertising is needed to maintain a given rate of sales thus advertising expenditures can be viewed as a capital good that depreciates over time and needs maintenance and repair 22 p 197 more recently weiss 25 among others has suggested that research and development r d costs might also be capitalized as such expenditures yield benefits mainly in the future 25 p 421 unfortunately most analyses of the intangible capital issue have been limited to advertising largely because no comprehensive data on r d were available until quite recently however important recent theoretical contributions on the topic and improvements in data availability now make it possible more completely to consider the intangible capital aspects of both advertising and r d expenditures here the intangible capital issue is investigated through use of a market valuation model in this approach significant future intangible capital effects of advertising and r d are suggested to the extent that current expenditures have significant effects on the market value of the firm given positive market value influences individual coefficient estimates can be used to estimate both the total stock of intangible capital as well as average annual depreciation rates for advertising and r d while these depreciation rate estimates are interfirm averages and undoubtedly err in individual instances they can be quite useful in indicating the general magnitude of corporate profit and tax misstatement due to current reporting and tax policies in section i below various articles closely related to this study are reviewed section ii develops a valuation model embodying intangible capital considerations the data are discussed in section iii and estimation results are presented in section iv and finally conclusions and implications for public policy are discussed in section v

some economic determinants of time series properties of earnings abstract the earnings time series literature in accounting focuses on the statistical characteristics of the processes which generate corporate earnings in order to further our understanding of earnings behavior this study investigates the question whether inter firm differences in these statistical characteristics autocorrelations and variances of earnings changes can be explained by economic factors various relationships between economic factors and earnings behavior are derived from the economic literature and examined empirically in this study findings indicate that autocorrelations and variability of annual earnings and earnings over equity changes are systematically associated with the following factors the type of product the height of industry barriers to entry a surrogate for degree of competition the degree of capital intensity operating leverage and the firm size

an optimal control of inventory under probablistic replenishment intervals and known price increase abstract the unit purchase price of products may increase or decrease for various reasons which influences the seller s and buyer s inventory control policies this paper develops an inventory control model when replenishment intervals are probabilistic and partial backordering in which an announced price increase happens and the buyer can make a special order before the price increase initiates inventory at the beginning of the period is not equal to zero and can be positive or negative amounts the main aim of this paper is to determine the optimum amount of replenish up to level in special sale offer this model is analyzed in two cases according to the inventory level in which the price increase happens and both cases are formulated to maximize the total saving function for placing a special order or not a closed form solution is obtained for the optimum amount of a special order two special cases with the replenishment intervals following uniform or exponential distributions are studied with sensitivity analysis the results indicate that a buyer can determine the optimal values of the maximum level of inventory and order quantity when the time between two consecutive replenishments is a probabilistic variable and the buyer experiences known price increase for which the total profit is maximized

the optimal retailer s ordering policies for deteriorating items with limited storage capacity under trade credit financing abstract under permissible delay in payments all previously published models implicitly assumed that the supplier would offer the retailer a delay period but the retailer would not offer the trade credit period to his her customer huang 2003 journal of the operational research society 54 1011 1015 developed a retailer s replenishment model to reflect the real life situations by assuming that the retailer also adopts the trade credit policy to stimulate his her customer demand in huang s model it is assumed that the goods are not perishable and the storage capacity is unlimited based upon the above argument we propose a two warehouse inventory model for deteriorating items under permissible delay in payments three theorems are developed to determine the optimal cycle time and numerical examples are given to illustrate these theorems finally the results in this paper generalize the results presented by huang 2003 journal of the operational research society 54 1011 1015

planning for shortages net present value analysis for a deteriorating item with partial backlogging abstract this paper develops inventory models to help answer strategic questions concerning whether planning for shortages offers financial benefits a production inventory system producing a deteriorating product in batches at a finite production rate with partial backordering is considered customers pay a deposit when placing a backorder backordered items receive a discount on the sales price as lost sales may lead to customers not returning the demand rate may depend on the fraction of lost sales we develop a cash flow based profit maximising net present value npv model without the inventory cost parameters commonly used in this context unit holding cost unit backorder cost unit deterioration cost and unit lost sales cost the model finds the optimal inventory policy just like npv models that discount the traditional parameters but has the advantage of not needing to estimate the value of the traditional parameters it is shown that in models based on discounting the traditional parameters the parameters are not exogenously determinable but are non trivial functions of non financial endogenous system parameters such as the production rate annual demand rate and backorder rate extensive numerical experiments illustrate how cash flow npv models provide insights into the value of planning for shortages and strategic choices about the design of the production inventory system it also provides insight into the classical problem of how to interpret unit backorder cost and unit lost sales cost the study indicates that these insights cannot be reliably obtained from npv models based on discounting unit backorder costs and unit lost sales costs

a deterministic inventory model for deteriorating items with two warehouses and finite replenishment rate abstract a deterministic inventory model for deteriorating items with two warehouses is developed when the replenishment rate is finite demand is at a uniform rate and shortages are allowed it is assumed that the rates of deterioration of item in the two warehouses may be different the model is analysed for the case of continuous release pattern several special cases are discussed and a numerical example is provided to illustrate the variation in optimum inventory level and optimum cost for varying shortage cost

the dynamics of corporate profits abstract industrial economics research has devoted little attention to long run considerations of market structure and performance relationships this paper provides several insights into the dynamics of corporate performance a dynamic duopoly model is provided in which new firm entry causes a convergence of profits toward a new equilibrium this process has been examined empirically and both the speed of profit adjustment and the level to which this process converged in the long run has been studied for germany it has been found that entry and mobility of firms led to a relatively quick profit convergence which is an indicator for the functioning of competition however the convergence process was not complete since it did not result in an equalization of profit rates across firms

organization markets and persistence of profits in italian industry abstract persistence of profits is found in a large sample of italian manufacturing firms inter cluster differences are remarkable in two respects i product markets where the degree of price differentiation is high and suggests that each cluster may correspond to a separate market segment ii internal organization where high profit firms appear to have moved towards less vertically integrated production structures while persistently low profit firms appear to have more integrated organizational forms

two warehouse partial backlogging inventory models with three parameter weibull distribution deterioration under inflation abstract in many inventory systems the effects of deterioration of physical goods have drawn much attention of various researchers in recent years the more the deterioration is the more the order quantity would be according to such consideration taking the deterioration rate into account is necessary thus in this paper i develop the two warehouse partial backlogging inventory model introduced in yang 2006 to incorporate three parameter weibull deterioration distribution the objective is to derive the optimal replenishment policy that minimizes the net present value of total relevant cost per unit time two alternative models are compared based on the minimum cost approach the study shows that the optimal solution not only exists but also is unique model 2 is still less expensive to operate than model 1 in the proposed model finally some numerical examples and sensitivity analysis on parameters are made to validate the results of the proposed inventory system

electricity market structure electricity price and its volatility abstract the transition of the singapore electricity market structure shows that real time pricing with vesting contracts appears more effective than day ahead or real time pricing with a cap in maintaining a low electricity price and its volatility

an income strategy approach to the positive theory of accounting standard setting choice abstract this paper is designed to provide additional evidence on the positive theory of accounting policy choice by combining individual accounting principles into firm income strategies these strategies were the dependent variable in a probit analysis where the independent variables were size management compensation industry concentration ratio systematic risk capital intensity and the total debt to total asset ratio the results indicate that four of these factors size management compensation concentration ratio and the total debt to total asset ratio have a significant association with the choice of a firm s income strategy this test provides strong evidence consistent with the positive theory of accounting standard setting choice we also present evidence that smaller firms and or firms in less concentrated industries do not appear to make accounting policy choice decisions that are consistent with this theory

persistence of profits in the long run a critical extension of some recent findings abstract recent discussions of the persistence of profits question have focussed on two econometric firm models which have been validated for several countries the paper gives a brief summary of the model concepts and of the most important findings for the countries in question both models are then applied to a data bank of german enterprises providing new results for one of them which has not been realized in germany yet finally the estimation results of the two models are examined by variance analysis this reveals that the convergence process is stronger than it has ever been perceived

the benefits of purely financial participants for wholesale and retail market performance lessons for long term resource adequacy mechanism design in april 2015 singapore introduced an anonymous futures market for wholesale electricity using data on prices and other observable characteristics of all competitive retail contracts signed from october 2014 to march 2016 a larger average quantity of open futures contracts that clear during the term of the retail contract a month before the retail contract starts delivery predicts a lower price for the retail contract this outcome is consistent with increased futures market purchases by independent retailers causing lower retail prices consistent with the logic in wolak 2000 that a larger volume of fixed price forward contract obligations leads to offer prices closer to the supplier s marginal cost of production a larger volume of futures contracts clearing against short term wholesale prices predicts lower half hourly wholesale prices both empirical results support introducing purely financial players to improve both retail and wholesale market performance the paper then outlines how a regulator mandated standardized futures market can be used as a long term resource adequacy mechanism for the wholesale market regime

two warehouse inventory models for deteriorating items with shortages under inflation abstract in this paper the two warehouse inventory problem for deteriorating items with constant demand rate and shortages under inflation is considered in contrast to the traditional deterministic two warehouse inventory model with shortages at the end of each replenishment cycle an alternative model in which each cycle begins with shortages and ends without shortages is proposed here the optimal solution not only exists but also is unique comparing these two two warehouse inventory models the study shows that the proposed model is less expensive to operate than the traditional one in the case of the inflation rate is greater than zero hence under the consideration of inflationary effect the proposed model is less expensive finally some numerical examples for illustration are provided