日益增長的國際需求將近期內市場價格 推到一個未知水準，當然來是隨機的。採購已被認定為全球競爭市場中主要能力，許多公司人員面對許多挑戰，其中最大的一項就是如何在原物料市場價格不確定狀況下依然能滿足廠內原物料的需求。採購市場中價格支付狀況會高度影響總成本，所以面對不確定價格的狀況下，何時該購買是一項重要決策。 如今， 原物料價格占採購總成本的比例越來高決 策的複雜性在於策者必須 判斷未來價格將上漲或下跌，因此對於決策者說已有的庫存量和一期市場價格訊息可以幫助判斷。除此之 外， 這篇文章加入了先期指標的概念幫助決 策者定適當的採購量。 依據先期指標的資訊來幫助我們預測價格趨勢，在 指標顯示下跌 時，等待機會購買；在價格顯示上漲透過分散訂避開高市場的風險。 ;Growing international demand increasing recently pushed prices to unknown level. Naturally,the future market prices are stochastic. Procurement has been identified as a main ability to compete in the global marketplace in a manufacture′s. Many procurement staff confronts one of the greatest challenges which are how to match the demand in the factory when material cost is always uncertainty. Price paid in procurement markets can highly influence the total cost.The decision to be made is facing fluctuating market price at which price to purchase. Nowadays, raw material price are responsible for an increasing portion of total procurement cost. One of the complexities that decision-maker must deal with is to judge the price increase or decrease in the future. Therefore, for decision-maker, the information of the inventory in previous period and the real market price can help them to determine the appropriate lot size in each period.We are going to take leading indicator into account and provide an ordering policy to fit different situations. According to leading indicator, help us predict the price trend.When the leading indicator show that the price might go down in near future, we would keep remained inventory or ordering little quantities to wait a better market price to purchase more; or, when the leading indicator show the price might go up in near future, we would purchase at low spot price or discrete order quantity to avoid the risk of price.