Abstract: Usage data representing resource accesses on a network by client devices in a plurality of households is accessed. Based on the accessed usage data, a set of the households that the usage data indicates are associated with a specified number and type of client devices is determined. A subset of the usage data is extracted, where the subset corresponds to resource accesses by client devices associated with the subset of households. Usage information is determined for the specified number and type of client devices based on the extracted subset of the usage data.

Abstract: The invention can enable monitoring of the display of content by a computer system. Moreover, the invention can enable monitoring of the displayed content to produce monitoring, information from which conclusions may be deduced regarding the observation of the displayed content by an observer. The invention can also enable monitoring of the display at a content display site of content that is provided by a content provider site over a network to the content display site. It is contemplated that the invention can be particularly useful with a computer network, including private computer networks and public computer networks. In particular, the invention can be advantageously used with computer networks or portions of computer networks over which video and/or audio content are transferred from one network site to another network site for observation, such as the World Wide Web portion of the Internet.