Spandas Lui tells us that eBay has begun to use "big data" to get site visitors to buy more stuff -- about 10 petabytes in raw data. At the Big Data Summit in Sydney, Hugh Williams, Ebay's vice president of experience, search, and platforms, said the company has been working to make its site search more interactive, Lui writes. The site uses data to make predictions about whether a listed item will sell and how much it will sell for, among other assumptions.