New Nielsen Data Likely to Shock Some Web Publishers
Nielsen told clients that it was going to change its methodology for @Plan, including more than tripling the number of sites included in the data, and shifting from a questionnaire to electronic meters to determine who had visited which sites. It also lowered the minimum size of a sample on which it collects data to 50 from 200.
Nielsen still uses quarterly surveys to determine offline behavior, and this is combined with electronic measurement to come up with the new data. Theoretically, the changes would produce much more granular results and perhaps remove an inherent bias toward well-known brands.
via adage.com
