Çok ürünlü sistemlerde yok satmaya dayalı ürün ikamesi durumunda envanter denetimi

In the retail industry, substitution is a commonly observed customer response to stockouts.The sales data of a particular product observed by a retailer is affected by substitutionsfrom other products. In practice, retailers make their inventory decisions withoutthe knowledge of the substitution effects on demand. These decisions can be improvedif the substitution rates are known. In this thesis, an inventory management problem isconsidered in the retail industry with multiple items, stock-out based substitution andlost sales. The retailer employs a fixed review period, order-up-to level system to controlthe inventory. The purpose of this study is to develop a method to determine the optimalorder up-to levels in the presence of stock-out based substitution. For given demandrates, substitution structure, length of review period, and the order-up-to levels, an analyticalmethod to approximately evaluate the performance of the system is presented. Themethod computes the expected sales, inventory levels of each product, number of substitutionsbetween all product pairs, service levels achieved for each product, and servicelevel achieved by the system. In a computational analysis of the problem, the computedresults are compared with values obtained with a simulation model to illustrate the effectivenessof approximation method. The approximation method is then used to determinethe order-up-to levels that maximize the expected profit. It is observed that incorporatingsubstitution information in retail inventory management can have a substantial effect toincrease the profit.