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. 当仓库缺货时，为获得更多订单以及补偿顾客因滞后供给遭受的损失，供应商会给予一定价格折扣。
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. 在过去多数的研究中，都假设年需求为固定已知且欠拨率为常数或是跟价格折扣成线性关系。
