本研究探討網路拍賣中商品的不同上架策略，對於賣家預期利潤的影響。上架策略包括三種形式：固定價格、一般次高家拍賣（簡稱「一般拍賣」）及立即購買次高價拍賣（Buy-It-now拍賣，簡稱「BIN拍賣」）。其中，一般拍賣僅需設定保留價格、固定價格上架只要設定直購價格，BIN拍賣則除了保留價格外，還需要設置直購價格。
網路拍賣雖然也是利用競標機制來議定價格，但和傳統拍賣具有許多相異之處。其中最大的不同，是網拍過程所需時間通常遠長於一般拍賣。為了解決這項問題，eBay發明了很多網拍獨有的制度。一為Proxy bid，即投標人只須鍵入願付最高價，而eBay將會自動化為其投標，這讓eBay拍賣實質上等同於次高價拍賣；另一個重要發明，就是「立即購買」選項的使用，這不但讓有時間折現的賣家有機會用自己可接受的價格提早出售，反之讓買家具有提前買進的機會。
因此，本文以理論模型證實，隨著賣家耐心程度增加，「立即購買」選項的價格將逐漸提升；對於完全耐心者而言，一般拍賣與BIN拍賣的效果無異。這進一步表明，折現愈大，賣家愈傾向於利用「立即購買」選項加速交易，以避免因折現造成的收益減少，從而有效提升預期折現利潤。

This study examines the impact of different listing strategies in online auctions on sellers' expected profits. The listing strategies include three formats: fixed price, second-highest price auction (referred to as ‘‘regular auction’’), and Buy-It-Now auction (referred to as ‘‘BIN auction’’). In a regular auction, only a reserve price needs to be set; for a fixed price listing, only a Buy-It-Now price is required, whereas the BIN auction requires both a reserve price and a Buy It Now price.
Although online auctions also use bidding mechanisms to determine prices, they differ significantly from traditional auctions. The most notable difference is that the duration of online auctions is usually much longer than traditional ones. To address this issue, eBay has developed several unique features for online auctions. One is the Proxy bid system, where bidders only need to enter the maximum price they are willing to pay, and eBay will automatically place bids on their behalf, effectively turning eBay auctions into second-highest price auctions. Another important innovation is the ‘‘Buy-It-Now’’ option, which allows sellers to sell at an acceptable price earlier, benefiting those with time-sensitive needs, while buyers get the opportunity to purchase immediately.
This paper uses a theoretical model to demonstrate that as sellers become more patient, the price of the ‘‘Buy-It-Now’’ option will gradually increase. For fully patient sellers, the effects of regular auctions and BIN auctions are equivalent. This further indicates that the greater the discounting, the more sellers tend to use the ‘‘Buy-It-Now’’ option to expedite transactions, thereby mitigating the loss of income due to discounting and effectively enhancing the expected discounted profit.

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