Audience commonality metrics for characterizing the relationship between networked media channels based on audience overlap of identified visitor entities and their related media consumption histories is disclosed. Audience commonality metrics may be scalars or multi-dimensional metrics and may take into account and/or be used in conjunction with data related to on- or off-network media channels, on- or off-network activities, sociographics and/or demographics. A system according to the current invention comprises access to a configuration, an input for receiving audience commonality data, an audience commonality metrics engine and an output for providing calculated audience commonality metrics. Data related to identified visitor entities may be received, determined and/or inferred from resources such as a cookie, log file, sniffer, firewall, proxy server, client agent, tracking pixel and/or tool.
AUDIENCE COMMONALITY AND MEASUREMENT