在今日的全球化市場中，激烈的競爭使得產品的生命週期越來越短，再加上需求的不確定性，更讓零售商在時尚產品的庫存管理上面臨嚴峻的挑戰。而用來描述新產品的採用與擴展過程的模型中，經過歷史資料驗證後發現Bass模型提供了良好的預測結果，因此，在此論文，我們在需求符合Bass模型的假設下，發展出一個模型來幫助零售商決定時尚產品的最佳訂購量。我們也考量了二次訂購機會與製造商提供數量折扣所帶來的決策影響，並在權衡大訂購量所帶來額外的持有成本與折扣的優惠後決定最佳訂購量。在論文最後透過數值分析，我們發現提供折扣的訂購量是影響此決策模型結果的最重要參數。

In today’s global market, fierce competition makes products’ life cycles become shorter. Retailers have great challenge on inventory management for fashion products according to the uncertainty of demand. The Bass model is addressed to describe the adoption and diffusion of new products and yields good predictions when applied to historical data. In this thesis, we develop a model for determining the optimal ordering quantity for a retailer considering customer demands following Bass diffusion model. We also ponder on the effects of two order opportunities and quantity discount policy providing by the manufacturer. The optimal ordering quantity is obtained after considering the trade-off between extra holding cost and benefits from discount. In the end of this research, we find the result of our model is susceptible to the breakpoint of discount policy with numerical analysis.

Altintas, N., Erhun, F., Tayur, S., (2008). Quantity discounts under demand uncertainty, Management Science 54(4), 777-792.
Bass, F. M., (1969). A new product growth for model consumer durables. Management Science 15(5), 215-227.
Bass, F. M., (2004). Comments on "A New Product Growth for Model Consumer Durables", Management Science 50(12), 1833-1840.
Burnetas, A., Gilbert, S. M., Smith, C. E., (2007), Quantity discounts in single-period supply contracts with asymmetric demand information, IIE Transactions 39, 465-479.
Choi, T.-M., (2007). Pre-season stocking and pricing decisions for fashion retailers with multiple information updating. International Journal of Production Economics 106, 146-170.
Chou, S.-Y., Chang S.-L., Yang W.-D., (2001). Optimal multiple delivery schedule for demand in logistic model, International Journal of Production Economics 73, 241-249.
Corbett , C. J., Groote X. de, (2000). A supplier’s optimal quantity discount policy under asymmetric information. Management Science 46(3), 444-450.
Fisher, M., Rajaram, K., Raman, A., (2001). Optimizing inventory replenishment of retail fashion products. Manufacturing & Service Operations Management 3(3), 230-241.
Ho, T.-H., Savin, S., Terwiesch, C., (2002). Managing demand and sales dynamics in new product diffusion under supply constraint, Management Science 48(2), 187-206.
Karakul, M. (2008). Joint pricing and procurement of fashion products in the existence of clearance markets. International Journal of Production Economics 114, 487-506.
Khouja, M., (1999). The single period (news-vendor) inventory problem: A literature review and suggestions for future research. Omega 27, 537-553.
Kim, K., Hwang, H., (1988). An incremental discount pricing schedule with multiple customers and single price break. European Journal of Operational Research 35, 71-79.
Kogan, K., Herbon, A., (2008). Production under periodic demand update prior to a single selling season: A decomposition approach. European Journal of Operational Research 184, 133-146.
Kurawarwala, A. A., Matsuo, H., (1996). Forecasting and inventory management of short life-cycle products. Operations Research 44(1), 131-151.
Lau, H.S., Lau, A.H.L., (1997). Reordering strategies for a newsboy-type product. European Journal of Operational Research 103, 557-572.
Lau, A.H.-L., Lau, H.-S., (1998). Decision models for single-period products with two ordering opportunities. International Journal of Production Economics 55(1), 57-70.
Li, J., Liu, L., (2006). Supply chain coordination with quantity discount policy. International Journal of Production Economics 101, 89-98.
Mahajan, V., Muller, E., and Bass, F.M., (1990). New product diffusion models in marketing: A review and directions for research. Journal of Marketing 54, 1-26.
Mahajan, V., Muller, E., and Wind., Y., (2000). New product diffusion models. Springer Science and Business Media Inc. USA.
Meade, N., Islam T., (2006). Modelling and forecasting the diffusion of innovation – A 25-year review. International Journal of Forecasting 22, 519-545.
Mostard, J., de Koster, R., Teunter, R., 2005. The distribution-free newsboy problem with resalable returns. International Journal of Production Economics 97, 329-342.
Rogers, E. M. 1962. Diffusion of Innovations. The Free Press, New York.
Silver, E.A., Pyke, D.F., Peterson, R., (1998). Inventory management and production planning and scheduling. John Wiley and Sons.
Sultan, F., Farley, J. U., & Lehmann, D. R. (1990). A meta-analysis of applications of diffusion models. Journal of Marketing Research 27, 70−77.
Weng, Z. K., (1995). Channel coordination and quantity discounts. Management Science 41(9), 1509-1522.