“Nielsen Cross-Platform Campaign Ratings takes the commercial exposures from an advertiser’s TV ads and its online ads, and reports on the combined audience for the campaign,” the company says. “This shows advertisers, agencies and publishers just how many people, by age and gender, are seeing their ad across TV and online – both combined, or exclusively across either platform. Double-counting is removed.

“This is important because, by showing the relative cost effectiveness of the separate TV and online parts of the campaign, the system now makes clear to brands what the best media mix of online and TV is – whether the goal is optimal efficiency or maximum incremental cover.”

Cross-platform ratings are produced through a combination of Nielsen’s Online Campaign Ratings data and TV data from Barb, the UK TV ratings body. Results are delivered in terms of reach, frequency, GRPs, unique audience and impressions – at a ‘by day’ level, during the campaign.

Based on the test run of the system, which also featured the involvements of Mecca Bingo and BSkyB, Nielsen says it has seen a variance in ‘incremental reach’ (the additional people who see a campaign online who would not have seen it on TV) of between 0.4% and 14.1% when looking at an advertiser’s specified audience for its campaign, with the average being 4.1%.

“The UK beta tests also show that incremental reach is affected by the age and gender of the desired audience for the campaign (see chart above, click to enlarge). For campaigns aimed at young men, adding online placements to a TV schedule tends to generate significantly higher incremental reach than for campaigns aimed at young women.

“Other early findings show that the bigger the size of a TV campaign, the lower the levels of incremental reach online. And people who see a campaign’s ads both online and on TV don’t necessarily see them more frequently than those who only see them on just one platform.”