The firm’s new Media Metrix 360 solution combines ‘person-level measurement', using its panel of two million internet users, with data from ad and website servers recording details of what pages were accessed.

ComScore has consistently argued that effective web audience measurement must count people, not computers – in other words it must be based on panel data rather than server data. Earlier this year it warned that, as various hybrid products come on the market, buyers should understand that “not all hybrids are created equal”.

CEO Magid Abraham said: “This new approach will effectively reconcile panel and server-based measurement and provide unified numbers that are fully consistent with the ad server counts used for advertising payments.”

The hybrid approach is an attempt to combine the benefits of panel-based measurement with the ability of census-level server data to reveal the ‘long tail’ of niche websites whose audiences are too small to be effectively measured using a panel.

ComScore has criticised ratings providers who rely on server data to produce web audience figures, arguing that this approach is vulnerable to inaccuracies caused by cookie deletion. Earlier this year it published a detailed criticism of the methodology of Quantcast, which provides free server-based audience measurement tools.

But others, including the president of the Interactive Advertising Bureau have called such panel-based systems “outdated”.
Media Metrix 360 will be introduced for the US and Canada in August, with the UK following in September and other countries in the last quarter of the year.