Both deals are ironic, because both Nielsen's National Audience Demographic data, and PRIZM are proxies of actual audiences derived from samples and/or geographic clustering that are used to infer how viewers and households within the actual TV universe behave. Google TV Ads is based on actual TV usage data generated from satellite and cable TV digital set-top devices.

The deal also follows a recent one between Nielsen and DataLogix (Online Media Daily, Nov. 2), a company that licensed PRIZM to do the same thing for advertisers and agencies making online audience buys through advertising networks and exchanges.

In all of these cases, media planners and advertisers would be using offline surrogates to make decisions for targeting people that they already have actual users' behavior for.

"This partnership brings more layers of audience data to our existing targeting tools," Google posted Thursday on the official Google TV Ads Blog. " In addition to demographic and interest dimensions from Nielsen and Equifax already available in our targeting tools, advertisers will now be able to layer on PRIZM segments to find their audience on TV through Google TV Ads. PRIZM categorizes US households into 66 unique segments, using attributes such as lifestage, income, social group, home ownership, employment, and education."

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