In 2000, Amazon, the large e-commerce vendor, apparently engaged in dynamic pricing, where the price it charges its customers today depends on these customers' actions in the recent past-including what they bought, how much they paid, and whether they paid for high-speed shipping-and personal data such as where they live. One customer reported that he had bought Julie Taylor's Titus for $24.49. The next week, he returned to Amazon and saw that the price had jumped to $26.24. As an experiment, he removed the cookie that identified him, and found that the price dropped to $22.74. Other DVDTalk .com visitors reported that regular Amazon customers were charged 3% to 5% more than new customers. Amazon announced that its pricing variations stopped as soon as it started receiving complaints from DVDTalk members. However, Amazon may have resumed this practice in 2007. (David Streitfeld, "Amazon Pays a Price for Marketing Test," Los Angeles Times, October 2, 2000:C1; David Streitfeld, "Amazon Mystery: Pricing of Books," Los Angeles Times, January 2, 2007.) What type of price discrimination is this dynamic pricing?