Study Of Co-Perchursing Problem For Perishable Items Based On Game Theory

One main objective of firm management is to reduce cost, purchasing as a part of production and operation, the related cost takes up a great proportion. In order to save cost, firms can set up coalition, making the inventory policies jointly. In this way, scale economic can be obtained, ability of negotiating with suppliers can be improved, so co-purchasing policy has been applied in management practice gradually. The key to apply co-purchasing successfully and stably lies in rational saved cost allocation, while the cooperative game theory provides efficient tool for the problem. In the literatures of studying co-purchasing, products without deterioration are mainly concerned, perishable items are not considered, while perishable items are common in our daily life.Based on research accomplishment, this paper contains following works:1. Firstly, on the basis of introducing the research background, meaning, and the study in the domestic and international, points out the main research problem and content, and research methods.2. Based on the assumption of EOQ model, considered the perishable items, added fixed decay rate, according to the problem of purchasing perishable items by single retailer, obtained co-purchasing problem under scattered inventory and centralized inventory, and transformed the cost allocation among retailers into cooperative game model. Then, with the game theory, discussed the properties of co-purchasing game and gave several solutions. Finally, did detail analysis and comparison with a numerical example, and the influence of decay rate is also discussed.3. Expanded co-purchasing problem under scattered inventory and centralized inventory, considered shortage, established corresponding co-purchasing game. Then made comparison with no shortage under scattered inventory and centralized inventory with numerical example, and discussed its properties with numerical simulation.4. Lastly, all achievement of the thesis is summed up, the innovation and shortcoming are point out, and some future directions for research is suggested.With the study, achieved following conclusions:1. For retailers, co-purchasing is better than purchasing alone, with cooperation, fixed ordering cost and total cost unit time can be saved. And with increase of decay rate, the saved cost by cooperation is greater, that's to say the more perishable of the products, the more cost can be saved.2. For the same purchasing problem, retailers can benefit more under centralized inventory than scattered inventory with no shortage, especially with the increase of decay rate, owing to the inventory cost advantage under centralized inventory reduced ordering times. In addition, when considered co-purchasing problem under scattered inventory, shortage policy is better than no shortage, more cost can be saved for every retailer.3. The corresponding co-purchasing games under centralized inventory and scattered inventory with no shortage both have no empty core, stated fair and reasonable cost allocation scheme existed for every retailer, with the scheme, no retailer will leave the grand purchasing coalition. For the game under scattered inventory with shortage, the result of numerical simulation states the core may be not exist, the purchasing coalition is no stable for retailers.4. In the problems of expanded co-purchasing, the corresponding cost allocation games may have empty core, the relationship of purchasing coalition is not stable. And under the same condition, shortage is better than no shortage.