• by David Goetzl  @dgoetzl, July 14, 2010

Nielsen said the industry group that evaluates media-measurement techniques has granted accreditation to its local ratings process in all 25 markets that use local people meters. The Media Rating Council review process led to accreditation of 15 markets for the first time, and renewed approval for the first 10 markets where Nielsen launched the service. 

MRC, which includes station groups and agencies, has now accredited LPM-based ratings in the 25 largest DMAs in the country, covering about half of its population.

The lengthy accreditation process involved Nielsen proving to the MRC its active/passive meter was indeed measuring all viewing. The deployment of A/P meters began several years ago and finished in 2009 as the digital transition was complete.

Nielsen has adopted several initiatives to satisfy the MRC, including a house code-check, where it checks every A/P meter in panel homes to ensure proper function. If malfunctions are detected, Nielsen has agreed to take action.

There is also a system to help stations that feel there may be ratings inaccuracies, including conducting surveys of the markets to identify potential problems. Nielsen will regularly monitor whether signal transmission to cable systems affects its ratings process. Back-up sites have been established for the 25 DMAs to ensure that if one data-collection site goes down, it can continue to gather viewing information. Similarly, Nielsen is launching a second site for its national service in Ohio to go along with its Tampa, Fla. base.