Analysing Bidding Trends in Online Auctions

Online auctions such as eBay are becoming increasingly more important mechanisms for people to buy and sell items online. In general, e-commerce is becoming fundamental to transacting business around the globe. With the added convenience of online transactions also comes the risk of electronic fraud. Although companies such as eBay have operated for the last 10 - 15 years, very little auction data has been collected and made publicly available or analysed, to the knowledge of the authors. Before any assertions about the amount of fraud in online auctions can be made, the underlying nature and structure of online auctions must be understood. In this paper we present definitions of a good auction from the viewpoints of the stake holders of the auction (e.g., bidder, seller, auctioneer, etc.) and then provide an analysis of auction data methodically collected from live eBay auctions. We collected data from 1005 auctions for three commonly available electronic devices. We show that the number of bids per auction is independent of the duration of the auction, and that the proportion of proxy bids is also approximately constant, for the duration of the auction. However, the final bid price achieved during the auction is shown to be related to the duration. Although these results are preliminary, we believe that they provide a significant insight into online auction behaviour.