While Nielsen has been reviewing and altering its weighting controls annually for years, it normally gives its clients plenty of time - at least a full year - to evaluate the changes before it makes them. The discussion surrounding this year's changes are based on only a few weeks of data, and some clients fear Nielsen is giving them the bum's rush, because the changes impact other parts of its business plans, especially its decision to begin reporting online viewing of TV programming in its ratings this fall.
For their part, Nielsen executives say they have made no decision to implement the changes, and will only make the adjustments if their clients approve them. They also say the actual impact on TV ratings for specific television networks will likely be negligible, and that the biggest reason for implementing the controls now is to give Nielsen the ability to recalibrate its ratings when there is a big shift in the number of households that have new computers with Internet access. Pat McDonough, the Nielsen executive overseeing the process, says that usually occurs during the Christmas holidays, and Nielsen spends a few weeks adjusting its ratings based on a variety of new consumer electronics equipment, including computers and broadband access.
McDonough said the timing surrounding the new weighting controls is unlike any Nielsen has implemented in the past, because it only just compiled universe estimates for households with computers connected to the Internet, and it will begin reporting TV viewing via the Internet this fall.
According to the data Nielsen has begun circulating with its clients, 69.7% of U.S. households now have a computer with broadband Internet access. Based on its current sample, Nielsen's panel over-represents those households by 1.7%, and under-represents households with no computers by 0.8%.
"The changes in ratings are really, really small," McDonough said of the impact those weighting controls would have on the ratings TV networks use to sell billions of advertising to agencies and advertisers.
She estimated that the rating adjustments created by those weights would ultimately compute to "thousandths" of a ratings point, or numbers so small that they wouldn't event impact the statistical rounding that goes into the numbers Nielsen reports.
That is small comfort for some Nielsen clients who are concerned that the ultimate, long-term impact of the weighting controls could be more significant, especially for networks that skew especially high or low with viewers living in households with or without Internet access. They also note that those estimates are based on only a week or two of data, vs. 52-weeks of data Nielsen normally gives its clients before making such changes.
"Even fractional declines in ratings can become costly over time," one Nielsen client notes. "Networks whose audiences are older are more likely to experience negative changes. Conversely, the younger the age profile of network the more likely the change is to be neutral or positive. In the final analysis, a measurement company does not weight unless its wants to see audience data change in some way because its sample is out of alignment."
Another concern among clients is that Nielsen's new estimates for Internet-connected households may not be accurate, and that it is not being benchmarked off of some reputable, objective, third-party source such as the U.S. Census.
"It is unclear how Nielsen collects some the information that goes into developing its sample universe estimates," said the Nielsen client, adding, "Full disclosure is essential."