When an item is in short supply, the supplier may give customers a price discount on the stock-out item to compensate for the inconvenience of backorder and get more orders. 當倉庫缺貨時，為獲得更多訂單以及補償顧客因滯后供給遭受的損失，供應商會給予一定價格折扣。
In the past, most of the published data assumes that the annual demand is deterministic and the backorder rate is in proportion to the price discount offered by the supplier. 在過去多數的研究中，都假設年需求為固定已知且欠撥率為常數或是跟價格折扣成線性關係。
