• by March 16, 2001

Here's an alternative to using Media Metrix and Nielsen numbers in planning your online buys.

DoubleClick and comScore Networks today announced that its jointly marketed online audience measurement product, netScore, is producing traffic estimates that closely match the server logs of individual sites, confirming that actual traffic to most websites is substantially higher than has been reported by other syndicated ratings services.

As an example of the degree to which site traffic has been understated by current ratings services, Media Metrix reported 51,983,000 unique U.S. visitors for Yahoo during December 2000, while netScore reported 81,262,000 unique U.S. visitors, a 56% difference.

Yahoo self-reported 181,000,000 unique worldwide visitors for December 2000, while netScore closely matched that number by reporting 177,000,000 unique worldwide visitors for that same time period. In contrast, Media Metrix reported 89,440,000 unique worldwide visitors for December 2000.

For the month of January 2001, Media Metrix reported 10,604,000 unique U.S. visitors to the AltaVista site and netScore reported 17,950,000 unique U.S. visitors for that same time period. This represents a 69% difference between Media Metrix and netScore numbers.

"The discrepancies between appropriately processed web logs and syndicated ratings data are well known, and for the longest time industry concerns about undercounted traffic have been dismissed as self-serving," said Magid Abraham, President and CEO, comScore. "netScore's data shows that sites' concerns have been valid."