Purchasing and supplies assignment Essay

rudiment epitomeIn materials forethought, the ABC analysis (or Selective Inventory Control) is an catalogueing categorization technique. ABC analysis divides an gunstock into three categories- A breaker points with in truth tight visualise and high-fidelity records, B positions with less tightly controlled and good records, and C items with the simplest controls possible and minimal records. The ABC analysis brooks a implement for identifying items that lead pret annul a signifi send awayt impact on over whatever entry salute, while also providing a mechanism for identifying diametrical categories of argumentation that will deal different c ar and controls. The ABC analysis suggests that inventories of an placement atomic number 18 non of equal value.Thus, the store is grouped into three categories (A, B, and C) in gear up of their estimated importance. A items ar very important for an governing body. Beca victimisation up of the high value of these A ite ms, frequent value analysis is required. In addition to that, an organization destinys to choose an appropriate localise pattern (e.g. Just- in- m) to avoid otiose capacity. B items atomic number 18important, but of course less important than A items and to a greater extent(prenominal)(prenominal) important than C items. Therefore B items are intergroup items. C items are margin bothy important.Advantages and Disadvantages of ABC Analysis InventoryActivity Based constituteing, or ABC, is a regularity of whateverocating overhead and direct expenses related to the most important activities of the company first. This process t come out ensembleows course owners and managers an opport building blocky to representter de exquisite the areas of manufacturing or deals that generate the most profit for the company. Inventory analyze under the ABC method is classified in order of profitability to the company. Class A document accounts for 80 percent of revenue, class B list for 15 percent of revenue and class C strain for 5 percent of revenue.Better Control of High-Priority InventoryABC ancestry analysis places tighter and more frequent controls on high-priority blood line. High-priority inventory, or class A inventory, is the class of inventory that nodes request most often. In manufacturing, class A inventory also ground create include the items most often used in the produceion of goods. Because Class A inventory is directly linked to the success of the company, it is important to constantly proctor the take on for it and ensure stock levels match that imply. With ABC analysis, your company rout out use its resources to prioritize control of high-priority inventory over inventory that has a lower impact on your bottom line.More in force(p) Cycle CountsUnder the ABC inventory analysis method, you after part allocate your resources more efficiently during vibration counts. A cycle count is the process of counting only certain items on sche duled dates. The relative frequency of your cycle counts and the items you choose to include depends on how often your inventory fluctuates. Once inventory is organized by class, you can focus regular cycle counts on class A inventory. Depending on your sine qua nons, it may be needed to count class B inventory as infrequently as twice per division and class C inventory only once per year. The ABC analysis method saves time and tire counting only the inventory required by the cycle for the class of inventory versus counting all inventory items each cycleDisadvantagesConflict with Other Cost SystemsThe ABC inventory analysis does not meet Generally Accepted Accounting Principles (GAAP) requirements and also conflicts with traditional belling trunks. Companies that use ABC methods mustinessiness operate two make uping agreements, wiz for internal use under the ABC method and another(prenominal) for compliance with GAAP. Traditional costing corpses generate the figures requ ired by GAAP. Traditional costing systems allocate cost drivers by the actual unit cost, rather than by the activity percentage of the cost driver. As a result, ABC cost assignments often differ from traditional cost system assignments.Requires Substantial mental imagerysThe ABC method requires more resources to brinytain than traditional costing systems. When cycle counts are performed, class A inventory must be r out(p)inely analyzed to determine if the inventory still consists of high-priority items. If an inventory piece is no perennial used or chartered as frequently, it is moved to another inventory classification. This constant process requires much more selective information preventionment and collectionJust in timeA strategy for inventory forethought in which raw materials and components are delivered from the trafficker or supplier immediately forwards they are compulsory in the manufacturing processAdvantages & Disadvantages of Just-in-Time InventoryCompanies turn over significant inventory control to suppliers with just-in-time inventory. Just-in-time (JIT) inventory refers to an inventory instruction system with objectives of having inventory readily accessible to meet demand, but not to a point of excess where you must stockpile extra reapings. Maintaining inventory takes time and has be, which is what motivates companies to implement JIT programs.Customer NeedsBalancing the goals of avoiding stock outs while minimizing inventory be is at the heart of just-in-time inventory. One of the main benefits of automated and efficient inventory replenishment systems is that you can promptly respond to reduced inventory levels. Companies are now equipped to trace back on stock in a given product category and ramp up inventory in another as client emergencys and interests change.Inventory costMinimization of inventory management be is a primary driver and benefit of just-in-time practices. Inventory management has cost, and when you reduce t he list of holding space and staff required with JIT, the company can invest the nest egg in business sector growth and other opportunities, points out the Accounting for Management website. You also allow less likelihood of throwing out product that gets old or expires, meaning reduced waste. CoordinationA wrong of managing a just-in-time inventory system is that it requires significant coordination between retailers and suppliers in the distribution channel. Retailers often put major trust in suppliers by syncing their computer systems with suppliers so they can more directly monitor inventory levels at stores or in distribution centers to initiate rapid response to low stock levels. This usually means build up of engineering science infrastructure, which is costly. This coordinated effort is more involving on the whole than less time intensive inventory management systems.RisksJust-in-time inventory is not without risks. By nature of what it is, companies development JIT intend to walk a fine line between having besides much and too little inventory. If company procureers fail to adjust quickly to increased demand or if suppliers have distribution problems, the business risks upsetting nodes with stock outs. If buyers over breed and buy extra inventory to avoid stock outs, the company could experience higher inventory cost and the potential for waste.Vendor managed inventoryTop of Form lav of FormVendor Managed Inventory (VMI).Bottom of FormVendor Managed Inventory or VMI is a process where the marketer creates orders for their clients based on demand information that they receive from the customer. The vendor and customer are bound by an agreement which determines inventory levels, pack rates and costs. This arrangement can improve supply chain performance but reducing inventories and eliminating stock-out situations. VMI, the vendor specifies delivery quantities sent to customers through the distribution channel utilise information obtai ned from Electronic Data replace (EDI). There are a number of EDI transactions that can form the basis of the VMI process, 852,855 and the 856. The first is the crossway Activity Record, which is cognize as 852. This EDI transaction contains the sales and inventory information such as give away product activity and forecast measures, such as sum sold ($)Quantity sold (units)Quantity on hand ($)Quantity on hand (units)Quantity on order ($)Quantity on order (units)Quantity received ($)Quantity received (units)The EDI 852 information can be sent from the customer to the vendor on a weekly basis or more frequently in high-volume industries. The vendor makes the order decision based on this data in the 852 transmission. The vendor reviews the information that has been received from the vendor and an order determination is made based on actual agreement between the vendor and customer. umpteen another(prenominal) vendors use a VMI packet package to assist them in determining order requirements. VMI software can be part of an ERP suitesuch as SAP or be a standalone selection such as products from Blue Habanero, LevelMonitor, NetVMI or others.The software will verify if the data as accurate and meaningful. It will calculate a reorder point for each item based on the data and any customer information such as promotions, seasonality or unused items. The quantity of each item available at the customer is compared with the reorder point for each item at each location. This will determine if an order is needed and the quantities required. The second EDI transaction that is used in VMI is the bribe order acknowledgment, which is known as the 855. This EDI document sent to the customer contains a number of fields including Purchase order of battle subjectPurchase Order DatePurchase Order Line itemQuantityPrice point NumberDescription of ItemFreight ChargeShip DateSome vendors supply an offer ship notice (ASN) to their customers to inform them of an incoming ord er, which is know as EDI 856. The ASN differs from the purchase order acknowledgement in both timing and content. The 856 is sent to the customer after the shipment has been made instead of at the time of the purchase order. Advantages of vendor managed inventoryOne of the benefits of VMI is that the vendor is responsible for supplying the customer when the items are needed. This removes the need for the customer to have significant safety stock. Lower inventories for the customer can lead to significant cost savings. The customer also can benefit from reduced purchasing costs. Because the vendor receives data and not purchase orders, the purchasing department has to spend less time on calculating and producing purchase orders. In addition, the need for purchase order corrections and reconciliation is removed which further reduces purchasing costs. Cost saving can also be found in reduced warehouse costs.Lower inventories can reduce the need for warehouse space andwarehouse resource s. When a business relies on vendor-managed inventory, its placing a big bet on that companys ability to deliver. The vendor has to be able to determine when to send new stock, what specific products to send and in what quantities. This can be beyond the means of a supplier that doesnt have the software, infrastructure or expertise in place to make that work. If just-in-time inventory turns into way-too-late shipments thanks to silly demand forecasts or a supply-chain breakdown, VMI isnt going to work.Disadvantages of vendor managed inventoryUnscrupulous PartnersEven with way out policies in effect, a business risks being taken advantage of by a supplier flavor to make its poem. For example, a vendor might ship an excessive amount of product at the end of the quarter and book it as revenue to boost its sales figures regardless of the customers demand. The customer may return the unneeded merchandise, but the vendor already has gotten what it wants out of the transaction. In add ition, VMI may require a company to share sensitive information with the supplier, which can leave it in a diffuse position should the relationship between the parties ever falter.Limited OptionsA vendor-managed inventory system can be bad for a business when it keeps the business from seeking better-suited or lower-cost options. Because VMI links the supply chain in concert so closely, it serves as a disincentive to make a change that necessitates changing the companys inventory management system. As a result, a business may find its inventory savings negated by settling for higher- priced or inferior goods.Market ResponsivenessCustomer cullences can change in a heartbeat, with favorites falling out of style and new items becoming more in demand. If your vendor doesnt supply a wide teeming range of products and your contract prevents you from going to the competition, you may be stuck with items your customers go intot want and no way to fix the problem. baffle sure your contr act doesnt draw together you so tightly to your vendor that you both sink together when the market changes.The manufacturer can chance upon some benefits from vendor managed inventory as they can gain access to a customers point of sale (POS) data makes their forecasting somewhat easier. Manufacturers can also work their customers promotional plans into forecasting models, which means enough stock will be available when their promotions are running. As a manufacturer has more visibleness to their customers inventory levels, it is easier to ensure that stock-outs will not occur as they can see when items need to be produced.INTRODUCTION TO MRPmanufacturing resource planning (MRP II) is defined as a method for the effective planning of all resources of a manufacturing company. Ideally, it addresses operational planning in units, financial planning, and has a simulation potential to answer what-if questions and supplement of closed-loop MRP. This is not exclusively a software func tion, but the management of people skills, requiring a dedication to database accuracy, and fitting computer resources. It is a total company management concept for using human and company resources more productively.MRP is a comprehensive system used for planning and scheduling materials requirement. It assists in improving the materials handling capability of an organization. But it has certain disadvantages. Some of the advantages and disadvantages of MRP have been discussed belowAdvantagesSome of the key benefits that can be derived from using an MRP system are Reduced per unit cost of production thus enabling an organization to price its products competitively Low inventory levels, especially for in-process materialsBetter response to market demandBetter customer functionReduced set-up and tear-down costsComprehensive material tracking and optimized production schedulingImprovement in capacity allocation and planningDisadvantagesFollowing are the disadvantages of an MRP syste mHigh costs and technical complexities in implementation. In addition, organizations, which use an MRP system need to spend considerable effort on installing necessary equipment (computers), training personnel, modifying the software to serve their specific needs, validating, testing, and eliminating possible errors, and maintaining the software. The time required for planning and implementing an MRP system is for the most part very long. Data entry and file maintenance requires considerable inputs in the form of training and instruction of the personnel. Dependence on forecast values and estimated lead-time can sometimes be misleading. The implementation of an MRP system can be effective only when there is a high degree of accuracy in the organizations operations. It requires high commitment from the top management of an organization.The management should educate its executives on the importance of MRP as a strategic planning tool. The success of an MRP system, like that of any o ther system depends on befitting implementation and right drill. Managers can derive more benefits if they use the MRP system as a management-planning tool. MRP needs enormous human efforts and care in continuously collecting the required information for the system. However, many organizations prefer to adopt MRP systems, as the advantages of the system outweigh its disadvantages. Are you searching trading operations Management expert for service of process with Advantages and Disadvantages of an MRP system questions?Advantages and Disadvantages of an MRP system topic is not easier to learn without external help? We at www.expertsmind.com offer finest service of Operations Management assignment help and Operations Management homework help. Live tutors are available for 247 hours helping students in their Advantages and Disadvantages of an MRP system related problems. We provide beat by step Advantages and Disadvantages of an MRP system questions answers with 100% plagiarism fre e content. We prepare lineament content and notes for Advantages and Disadvantages of an MRP system topic under Operations Management theory and study material. These are avail for subscribed substance abusers and they can get advantages anytime.Economic Order Quantity (EOQ)Economic order quantity (EOQ) is the order quantity of inventory that minimizes the total cost of inventory management. Two most important categories of inventory costs are guild costs and carrying costs. Ordering costs are costs that are incurred on obtaining additional inventories. They include costs incurred on communicating the order, transportation cost, and so on Carrying costs represent the costs incurred on holding inventory in hand. They include the opportunity cost of money held up in inventories, storage costs, spoilage costs, etc. Ordering costs and carrying costs are quite opposite to each other. If we need to minimize carrying costs we have to place small order which increases the ordering costs . If we want minimize our ordering costs we have to place few orders in a year and this requires placing large orders which in turn increases the total carrying costs for the period. We need to minimize the total inventory costs and EOQ model helps us just do that. integral inventory costs = Ordering costs + Holding costsBy taking the first derivative of the function we find the following equation for minimum cost EOQ = SQRT(2 Quantity Cost Per Order / Carrying Cost Per Order)ExampleABC Ltd. is engaged in sale of footballs. Its cost per order is $400 and its carrying cost unit is $10 per unit per annum. The company has a demand for 20,000 units per year. Calculate the order size, total orders required during a year, total carrying cost and total ordering cost for the year.SolutionEOQ = SQRT(2 20,000 400/10) = 1,265 unitsAnnual demand is 20,000 units so the company will have to place 16 orders (= annual demand of 20,000 divided by order size of 1,265). Total ordering cost is hen ce $64,000 ($400 multiplied by 16). Average inventory held is 632.5 ((0+1,265)/2) which means total carrying costs of $6,325 (i.e. 632.5 $10).businesses require an efficient inventory system to maximize profit. The Economic Order Quantity model is a commonly used element of a continuousreview inventory system. It is based on a canon that calculates the most economical number of items a business should order to minimize costs and maximize value when re-stocking inventory. Small business owners should evaluate the advantages and disadvantages of this inventory model before implementing it.DISADVANTAGESMinimizes Storage and Holding CostsStoring inventory may be expensive for small business owners. The main advantage of the EOQ model is the customized recommendations provided regarding the most economical number of units per order. The model may suggest buying a larger quantity in fewer orders to take advantage of discount bulk buying and minimizing order costs. Alternatively, it may point to more orders of fewer items to minimize holding costs if they are high and ordering costs are relatively low.Specific to the jobMaintaining sufficient inventory levels to match customer demand is a balancing act for many small businesses. Another advantage of the EOQ model is that it provides specific meter ill-tempered to the business regarding how much inventory to hold, when to re-order it and how many items to order. This statics out the re-stocking process and results in better customer service as inventory is available when needed.Complicated Math CalculationsThe EOQ model requires a good brain of algebra, a disadvantage for small business owners lacking math skills. Additionally, effective EOQ models require detailed data to calculate several figures. For example, the key formula of the model calculates the square root of 2DS/H, where D is the number of units purchased annually, S is the fixed ordering charge, and H is the holding cost per unit. Rent or mortgage payments, utility costs and property taxes are required just to calculate H.Based on AssumptionsThe EOQ model assumes steady demand of a business product and immediateavailability of items to be re-stocked. It does not account for seasonal or economic fluctuations. It assumes fixed costs of inventory units, ordering charges and holding charges. This inventory model requires continuous observe of inventory levels. The effectiveness of the basic EOQ model is most limited by the assumption of a one-product business, and the formula does not allow for combining several different products in the same .INTRODUCTION TO ERPWhat is ERP? It means enterprisingness resource planning, which itself means planning the resources in an enterprise (business). So, this abbreviation simply means, that this is a way of using the resources in a company more effectively. Notice, that this is not some kind of software, this is an ideology. Some companies build applications, that work according to this i deology, called ERP solutions. But there is something more there the developers of such solutions build their application implementing some silk hat business practices in it, and this is one of the most valuable features of ERP systems. The so called know-how is the most common thing that many of the small businesses out there lack. And this could be the difference between the successful, fast flowing company and the median(a) company. At some point of the life cycle of an enterprise, the need of such a system becomes inevitable. The before managers visualize this, the better.As the company grows, its control becomes more and more sticky designate. An integrated solution, like ERP software, could be really ministrant in this situation. Every small company, that wants to grow big just needs to use an ERP system. Some big corporations even would not do business with you, if you hadnt such a software implemented and working in your business. Such a solution is a proof for higher quality and that you are running your enterprise well and effectively.There are many many benefits coming from these systems, later(prenominal) well talk about them more. ERP solutions are from the group of integrated systems, which means that they are built to integrate any part of your business. Initially the manager in a small company can coordinate the different departments relatively easy, but when the company starts to grow, the same happens with the size and number of departments. The coordination between them becomes really hard and expensive. At some point of time a crisis of control is inevitable. ERP systems can bemanagers best friend then, because this is one of their main purpose to integrate your business.Advantages & Disadvantages of ERP (Enterprise Resource Planning) SystemsIn order to understand computer networks better, it would be helpful to have an overview of the applications running on the network. ERP or Enterprise Resource Planning is an important enterpri se application that integrates all the individual department functions into a single software application. ERP Systems make it easier to track the workflow crossways divers(a) departments. They reduce the operational costs involved in manually tracking and (perhaps) duplicating data using individual & disparate systems. In this article, let us have a look at the advantages and dis-advantages of implementing ERP (Enterprise Resource Management) Software Systems.Advantages of ERP (Enterprise Resource Planning)1. Complete visibility into all the important processes, across various(a) departments of an organization (especially for elder management personnel). 2. Automatic and coherent workflow from one department/function to another, to ensure a smooth transition and quicker completion of processes. This also ensures that all the inter-departmental activities are properly tracked and none of them is lost out. 3. A unified and single reporting system to analyze the statistics/status e tc. in real-time, across all functions/departments. 4. Since same (ERP) software is now used across all departments, individual departments having to buy and maintain their own software systems is no longer necessary. 5. Certain ERP vendors can extend their ERP systems to provide Business Intelligence functionalities, that can give overall insights on business processes and identify potential areas of problems/improvements. 6. Advanced e-commerce integration is possible with ERP systems most of them can handle web-based order tracking/ processing.7. There are various modules in an ERP system like Finance/Accounts, Human Resource Management, Manufacturing, Marketing/Sales, Supply Chain/Warehouse Management, CRM, work out Management, etc. 8. Since ERP is a modular software system, its possible to implement either a few modules (or) many modules based on the requirements of an organization. Ifmore modules implemented, the integration between various departments may be better. 9. Sinc e a Database system is implemented on the backend to store all the information required by the ERP system, it enables centralized storage/back-up of all enterprise data.10. ERP systems are more secure as centralized security policies can be utilise to them. All the transactions happening via the ERP systems can be tracked. 11. ERP systems provide better company-wide visibility and hence enable better/faster collaboration across all the departments. 12. It is possible to integrate other systems (like leave off- canon reader, for example) to the ERP system through an API (Application Programing Interface). 13. ERP systems make it easier for order tracking, inventory tracking, revenue tracking, sales forecasting and related activities. Disadvantages of ERP (Enterprise Resource Planning)1. The cost of ERP Software, planning, customization, configuration, testing, implementation, etc. is too high. 2. ERP deployments are highly time-consuming projects may take 1-3 years (or more) to ge t finish and fully functional. 3. Too little customization may not integrate the ERP system with the business process & too much customization may slow down the project and make it difficult to upgrade. 4. The cost savings/ payback may not be realized immediately after the ERP implementation & it is quite difficult to measure the same. 5. The participation of users is very important for successful implementation of ERP projects hence, exhaustive user training and simple user interface might be critical. But ERP systems are generally difficult to learn (and use).6. There peradventure additional indirect costs due to ERP implementation like new IT infrastructure, upgrading the WAN links, etc. 7. Migration of existing data to the new ERP systems is difficult (or impossible) to achieve. Integrating ERP systems with other stand alone software systems is equally difficult (if possible). These activities may consume a lot of time, money & resources, if attempted. 8. ERP implementations are difficult to achieve in modify organizations with disparate business processes and systems. 9. Once an ERP systems is implemented it becomes a single vendor lock-in for further upgrades, customizations etc. Companies are at the discretion of a single vendor and may not be able to talk terms effectively for their services. 10. Evaluation prior to implementation of ERP system is critical. If this stepis not done properly and experient technical/business resources are not available while evaluating, ERP implementations can (and have) become a ill luckADVANTAGES AND DISADVANTAGES OF BARCODINGBar codes consist of immobilizes and spaces that vary in width. The contains and spaces on a bar code correspond to numbers and letters that represent descriptive data. Scanners skip the bar code to find the alike description of the item, including the make and model of an item and its price. Many stores and shops commonly use bar code technology for stock inventory. Its also used to sc an when a customer wants to purchase it. There are advantages and disadvantages regarding the use of bar code technology.the Disadvantages of Barcodesdisadvantages of Bar CodesTimeIn the blink of an eye, scanning a bar code instantly displays the product name, type of product and price. Bar codes also have a 12-digit product number that when entered also produces the same information. However, if a cashier has a long line of impatient customers, go into the product details of each item is time-consuming, especially in grocery stores where each customer usually purchases multiple items. Although bar codes are a huge advantage when it comes to time, it can also be a disadvantage if the bar code on the product doesnt correspond to the right product, or the bar code electronic scanner isnt workingInventoryInventory is a huge component of any goods and services business. Keeping track of inventory can be a tedious, time-consuming and difficult task to do without a bar code scanner. With a bar code scanner, shop owners simply scan the bar code on the items and keep track of the stores inventory that way. When an individual purchases an item, the scanner transmits this information to the computer and its calculated on the stock inventory via computer technology. The major disadvantage here is if the cashier sees a number of items that look or seem the same and scans one item multiple times to savetime. Each item and type of item has a unique bar code and must be scanned separately. As a result, this could affect inventory.LabelsLabels make it easy for bar code scanners and computers to recognize the product item and vendor name. But when a label is change or non-existent, it poses problems. damaged labels make it difficult for the cashier to scan. Even the 12-digit number on the label may be damaged to the point where it is not legible. When this occurs, the checkout process is significantly delayed while the same product is desire out and brought to the cashier for scanning. In addition, some products, such as fruits and vegetables at grocery stores, dont have labels, which potentially cause delay. However, cashiers are usually trained to remember the 12-digit number corresponding to items without labels.CostsWhile bar code technology drastically reduces the time and energy spent on inventory and checkout procedures, it is costly. Businesses that want to implement bar code equipment and technology have to withstand the growing industry of doing so. This includes training employees, installing the equipment, expensive printers and the time spent entering codes for labels. However, despite the disadvantages with start-up, the bar code technology benefits businesses in the long run. CONCLUSION ON THE ABOVE INVENTORY MANAGEMENT TOOLSOne should start by saying that inventory management is the active control program that facilitates the management of sales, purchases and disbursements. The inventory management is all about special software that would reduce the costs and human efforts required to create invoices, purchase orders, various receiving lists, or payment receipts. The inventory management attempts to coordinate all the efforts in the warehouse, retail and other product lines in order to develop better controls of the processes that go inside the organization. Speaking about a particular software, I would like to note that one of the many is available at http//www.advanceware.net/modules.asp. The software is said to provide allthe needed inventory management tools in just one package. The website provides a demo adaptation of the software where one is able to explore the shipping module.The software allows the company to print serial numbers on an invoice, set a default tax rate, generate several types of reports, receive and process various customer/vendor returns, and place/process customer orders in various currencies. As for the inventory management in the workplace I would like to note that because I work in the hotel industry, the inventory management is different here than in other industries. The inventory that hotel manages is the inhabit space available for rental.One should understand that because hotel industry sells services the improper inventory management might mean that the hotel will not gather up all the rooms. Thus, the inventory management for the hotel industry should focus on the timeliness with respect to room occupation and marketing. The inventory management should also account for the food, towels, bed sheets, and other items required for the daily hotel operations. The inventory management should assure that the hotel rooms are filled right after they are freed, otherwise, the hotel would lose out since unlike tangible inventory, the service hotel industry offers cannot be sReferencesHarris, Ford W. (1990) Reprint from 1913. How Many Parts to Make at Once. Operations Research (INFORMS) 38 (6) 947950. doi10.1287/opre.38.6.947. JSTOR 170962. Retrieved Nov 21, 2 012. edit Hax, AC and Candea, D. (1984), Production and Operations Management, Prentice-Hall, Englewood Cliffs, NJ, p. 135 Grubbstrm, Robert W. (1995). Modelling production opportunities an historical overview. International Journal of Production Economics 41 114. doi10.1016/0925-5273(95)00109-3. Nahmias, Steven (2005). Production and operations analysis. McGraw Hill Higher Education. edit Altintas, N. Erhun, F. Tayur, S. (2008). Quantity Discounts Under Demand hesitancy. Management Science 54 (4) 777792. doi10.1287/mnsc.1070.0829. edit Andrew Caplin and John Leahy, Economic