近年來，隨著網際網路的普及，電子商務蓬勃發展，線上拍賣蔚為風氣，然而新事業往往帶來新的風險。在電子商務環境下，企業應採行必要的控制，以使線上交易順利安全地完成，並確保客戶的隱私、增加顧客的信賴感，進而提昇企業營運與聲譽。線上拍賣所涉及外部人士相當多，其所提供的個人及競價交易資料相當龐雜。因此，從事線上拍賣之公司執行內部控制時，除考慮其內部環境之控管外，也應考量其對於線上拍賣參與者之影響。 本研究之目的在於探討線上拍賣環境下的交易控制。根據相關文獻，本研究彙整出一套線上拍賣交易控制實務的評估架構及準則，以國內兩大線上拍賣網站：Yahoo！與eBay為個案，進行比較及分析，並作為設計研究問卷之基礎。其次，本研究利用問卷調查目前參與線上拍賣者以及潛在使用者對於現有線上拍賣交易控制之看法，藉以瞭解填答者對於不同交易控制構面之滿意度及其影響因素。 經由上述之個案研究及問卷資料統計分析，本研究發現： 1、 在個案分析及比較方面，就隱私性而言，兩個案網站皆僅提供制式的隱私權政策，使用者無法選擇部分同意，而被迫提供超過其意願之資料或無法禁止第三者使用其資料。在交易完整性方面，兩個網站皆提供相當完整但繁複之政策，但可考慮將所有政策彙整歸類，以便於使用者夠迅速取得必要之資訊。至於交易安全性方面，兩網站可增加對使用者之溝通，讓使用者不但明瞭其自身的義務，亦能瞭解企業對保護整體拍賣系統之承諾。 2、 就滿意度而言，eBay使用者對於該網站政策之滿意度高於Yahoo！使用者，但Yahoo！使用者對於該網站提供之交易平台之滿意度則高於eBay使用者。 3、 就問卷統計分析結果而言，拍賣網站使用者最為重視：（1）網站必須足以完善保障其個人資料及隱私權，以及（2）網站足以確保交易之完整性。換言之，使用者擔心其所提供之各項資料考能遭到竊取、盜用或不當使用，並憂慮交易過程中可能發生的詐欺或不公平行為。不過，使用者雖然相當擔心其所面臨的風險，其對於網站相關政策之瞭解，卻不是全面及深入的，並認為此等政策僅有普通的完善度，滿意度也僅略高於普通。 4、 使用者及潛在使用者對於拍賣交易之整體看法顯著不同，前者較後者傾向肯定線上拍賣，並有較高的願意繼續於線上交易，即使在發現可能遇見交易風險時，也較傾向繼續使用該交易平台。 5、 問卷發放方式會影響實證結果。本研究問卷同時採用網路發放及現場發放，兩種來源回收的問卷在基本資料上有以下之差異： （1） 年齡差異：網路樣本較現場樣本年輕。 （2） 職業差異：網路樣本多為學生，現場樣本多為實務界人士。 （3） 交易次數差異：網路樣本較現場樣本有較多次的交易經驗。 （4） 上網時數差異：網路樣本之上網時數高於現場樣本。 進一步分析顯示，兩組樣本對於政策之認同、資料安全、政策瞭解度、危害考量及整體滿意度皆有顯著差異。網路填答者對網路政策認同度高，較不擔心資料安全問題，遭遇危害後也較願意繼續使用交易平台，整體滿意度也較佳，但卻不如現場填答者願意瞭解拍賣網站政策。因此，後續研究者似應考量不同問卷發放方式及對象，對於其實證結果可能帶來的影響。 6、 綜合上述可知，無論就個案比較分析或問卷結果而言，兩個案網站之隱私性、完整性及安全性政策皆未臻完備，仍有進步的空間。換言之，現有使用者及潛在使用者對於目前交易平台所提供之相關政策之雖非不滿意，卻也不甚肯定其完善性。基於隱私性、完整性以及安全性政策之完善程度為顧客選擇交易網站之重要原因，兩網站似應進一步改善其相關政策，以增進顧客對其之信任及滿意度。 / In recent years, with the prevalence of the Internet, electronic commerce becomes a popular form of business. More people are participating in online auctions. However, new business brings new risks. In electronic commerce, organizations must implement necessary controls to secure their online transactions and to protect their customers’ privacy. By gaining the customers’ trust, a corporation can build up its reputation and enhance its businesses. Online auction involves numerous parties and lots of personal and transaction data. Consequently, when designing and implementing its internal controls, an online auction firm should consider not only the control of its internal environment, but also the effects of these controls on the outside parties involved. The purpose of this study is to explore the transaction controls for online auction. Based on relevant literature, we developed a set of guidelines for evaluating the transaction controls for online auction. Two famous online-auction sites, Yahoo! and eBay, were compared and analyzed with these guidelines. The results also served as the basis of our research questionnaire, which was used to collect data from both the current online auction participants and the potential users. The survey provided evidence with respect to the respondents’ overall opinion of online auction transaction controls, as well as their levels of satisfaction on different aspects of controls and the factors affecting their satisfaction. Our research findings are as follows: 1. Both Yahoo! and eBay provide standardized privacy policy statements. The users do not have the option for partial agreement. They are often forced to provide extra personal data and can’t prevent the third party’s use of the data. As for transaction integrity, both online-auction sites provide fairly complete and detailed policies. However, finer summarization and classification of these policies is needed to facilitate the users’ access of the information. For transaction security, both websites should improve the communication with their users such that the commitment to secure their online auction systems is well understood. 2. In general, eBay users are more satisfied with its policy than Yahoo! users. However, Yahoo! users’ level of satisfaction of the transaction platform is higher than that of eBay users. 3. Based on the survey, the users care most about a website’s ability to protect their personal data and privacy as well as the integrity of online transactions. That is, they are concerned about the possible theft and misuse of their data and the fraud or inequity occurred in the transaction process. However, given the concern on these risks, the users’ understanding of or attempt to understand the related policies is not as thorough or comprehensive as it can be. Their satisfaction with the related policies is only slightly above average. 4. The overall opinion about online auction is significantly different between the current users and non-users (potential users). The former group has a more positive view on online auction and is more willing to continue their online transactions. Even with the potential transaction risks, they intend to remain on the same transaction platform. 5. Different ways of distributing research questionnaires may affect the survey results. In this study, we use both on-line survey (through a BBS) and on-site survey. These two groups of respondents have the following differences in profile: (1) the on-line respondents are, on average, younger than the on-site respondents, (2) most of the on-line respondents are students, whereas the on-site respondents are mostly practitioners, (3) the on-line respondents use the on-line auction more frequently, and (4) the on-line respondents spent more time on the Internet. Additional analyses indicate that the above two groups differ significantly in the acceptance and understanding of website policies, the concern over data security and risks, as well as their overall satisfaction of the websites. In general, the on-line respondents are more positive toward the websites’ policies, less concerned about data security, willing to accept the potential risks, and more satisfied with the websites’ transaction controls. Therefore, future research should consider the potential effects of different ways of distributing questionnaire on its survey results. 6. In summary, both online auction websites’ policies on privacy, transaction integrity and transaction security are not as comprehensive or complete as proposed by the relevant literature. Both users and non-users are only moderately satisfied with these policies. Since the completeness of the above policies are determining factors in the users’ choice of transaction platform, both websites should further improve their policies on transaction controls and privacy to enhance their customers’ confidence and satisfaction in using the platforms.