(19) United States
(12) Patent Application Publication (io) Pub. No.: US 2003/0163370 Al
Chen et al. (43) Pub. Date: Aug. 28,2003
(75) Inventors: Simon S. Chen, Los Altos, CA (US);
Yen Whei Chow, San Jose, CA (US);
Todd Tao Zhou, Milpitas, CA (US)
George I. Lee
McDonnell Boehnen Hulbert & Berghoff
300 S. Wacker Drive
Chicago, IL 60606 (US)
(73) Assignee: NetRatings, Inc.
(21) Appl. No.: 10/242,305
(22) Filed: Sep. 12, 2002
Related U.S. Application Data
(63) Continuation ol application No. 09/266,790, filed on Mar. 12, 1999, now abandoned.
A method and apparatus for allowing the collection ol information regarding visits to the pages ol a data network such as the Internet, and the number ol separate images viewed is described. Hie described method overcomes various prior art limitations including providing for improved accuracy in reporting the number ol times a banner image, such as an advertisement, is viewed; providing improved methods and apparatuses for efficiently identilying unique banner images viewed; providing an improved method and apparatus for configuring a network user's computer so that interference Irom the data collection process with the normal operation ol the computer is minimized; providing an improved method and apparatus for efficiently calculating a checksum to allow unique identification ol a banner image viewed by a network user; and providing an improved method and apparatus for determining whether the network user used the browser BACK button to view a page and, il so, to count the banner images viewed.