This activity is a result of a number of start-ups and other underdogs trying to be more competitive with Nielsen. Since the company’s recent privatization, it has been operating without industry accreditation for both its local and national TV ratings. This leaves others with no options but to compete. Nielsen’s ratings remain the bedrock of most deals between TV networks and advertisers, but many of the traditional media companies have started to offer new kinds of measurement pacts using companies including iSpot, VideoAmp and Comscore,