• by Joe Mandese  @mp_joemandese, June 12, 2009

RSS is an acronym that stands for the online publishing term really simple syndication, but it recently proved to be anything but simple for online audience researcher Nielsen. In an especially embarrassing glitch that illustrates how unreliable and antiquated its current system is for measuring online audiences, an anomaly in the RSS feeds a single user had set up to receive news updates from three publishers - Foxnews.com, NYTimes.com, and USAToday.com - caused their estimates to be grossly inflated, and has triggered a deeper probe by clients into the technology and methods Nielsen uses to measure online audiences.

Nielsen is releasing restated numbers for those three publishers today - all significantly downward - and is poised to rollout a brand new audience measurement system it says will prevent that kind of glitch from ever happening again (see related story), but the debacle is raising new questions about the reliability of online audience measurement.

"This is an extremely rare situation, which we've addressed and fixed," a Nielsen spokesman tells Online Media Daily, adding, "It cannot occur in the new methodology, because of improved filtering techniques."

Actually, he said there are two advantages of the new measurement system. One are enhanced filters that theoretically would detect and weed out anomalies such as the RSS glitch before they get factored into published audience estimates. The other is that the sample is so much larger - ten times bigger than Nielsen's current 20,000 sample - that even if a user glitch were to slip through the filters, it would have a much less significant impact on the overall base.

But the RSS gaff couldn't have come at a worse time for Nielsen, which already was being scrutinized by big publishers such as NYTimes.com, is converting to a brand new system, and is under increased competition from a wide variety of rivals using disparate methods they each claim are superior and more accurate than Nielsen's.

It's not entirely clear what actually happened with the glitch, but Nielsen executives say they discovered it when some big publishers detected "wobbly" numbers, and asked Nielsen to investigate. The cause, Nielsen said, was the way a single panel member had configured his RSS feed for news publishers that caused it to "ping" Nielsen's online ratings meter every time a new news update came in from those publishers.

"Who knew this could happen," said a Nielsen executive, adding, "We know now, and it cannot happen again because of the new methodology."

In an official notice sent to clients earlier this week, Nielsen said the problem was uncovered during "normal Nielsen Online production processing and quality assurance checks," which led to the discovery of "ineligible panelists."

Nielsen did not detail the nature of the problem, but said it "contributed to a material artificial inflation of page views and minutes in the January through April 2009 reporting for the following entities: NYTimes.com (Brand), Fox News Digital Network (Brand), FoxNews.com (Channel), and USATODAY.com (Brand). These invalid URLs had no material impact on Unique Audience."