CHICAGO -- Given the sheer number of operating systems and devices, mobile advertising is a challenging medium to measure, but it could benefit greatly from so-called "big data," says Joan FitzGerald, VP of TV & Cross-Media Solutions at comScore. Beet.TV interviewed her at the Beet.TV Video Advertising Summit in Chicago to discuss advances in mobile and online measurement. The best strategy for mobile measurement may be one that blends consumer research with census data to give an overall picture of mobile reach, she explains to Beet.TV in this video interview. comScore is starting to do that with some of its measurement tools, such as as its Mobile Metrix 2.0, a mobile behavioral measurement service. In general, advertisers in digital video are eager to compare TV campaigns to online campaigns, and that's why the use of the GRP is rising across brands, agencies and online publishers. Another measurement tool gaining traction is comScore's Validated Campaign Essentials that lets advertsers count impressions actually seen by consumers, leaving out impressions below the fold that might not be seen. "This lets you create greater comparability between TV and online and lets advertisers count impressions seen by consumers," she says in this video.comScore introduced Validated Campaign Essentials earlier this year. It was accredited by the Media Ratings Council in August and has already seen hundreds of campaigns rely on it, FitzGerald tells us.