• by Joe Mandese , January 4, 2005

Citing "an unusual set of hardware failures" in its data collection systems, Nielsen Media Research alerted customers on Monday that it would "withhold" ratings for 12 markets in the Western U.S. for Dec. 31, 2004, until it can recover and reprocess the data.

Nielsen did not disclose the nature of the hardware problems, but said they impacted ratings for many of the West's biggest media markets, including: San Diego, Los Angeles, Los Angeles Hispanic, Denver, Sacramento, Salt Lake City, San Francisco, Phoenix, Seattle, Las Vegas, Albuquerque and Portland.

"The hardware failures caused a disruption to the calling-in process from Nielsen's sample households in these 12 markets," stated the advisory. "Not all households were able to call in with their viewing and tuning data for Dec. 31."

Nielsen said the glitch prevented it from collecting sufficient data to release ratings in the 12 markets, but that they all appeared to be reporting normal data on Jan. 1 and Jan. 2, 2005.

While the flaw also affected homes in Nielsen's national people meter sample in Los Angeles and San Francisco, Nielsen said they were not impacted severely enough to fall below its minimum standards for reporting ratings.

While Nielsen indicated the malfunction was due to some kind of anomaly caused by its hardware supplier, the timing of the equipment failures is awkward because Nielsen has been under fire for excessive "fault" rates in certain households, particularly African American, Hispanic American and households with five or more family members.

"We have been working continuously with our hardware vendor since Dec. 31 to identify the problems, fix them and make sure procedures are in place so this does not happen again," Nielsen assured its clients. "We are also working to see if data from these 12 markets can be recovered and reprocessed."