> I'll still give Nielsen props for making people think
> about "the numbers" and using their influence to bring light to the
> challenges of new media measurement. At the end of the day though, it's
> still tough data to believe since I have no insight as to whether the
> panel
> suffers from coverage error and selection bias, regardless of the
> technical
> challenges to measuring time on the web.

Sure, let's stipulate these panels have all kinds of measurement problems as
it is, which is part of the reason for going through the audits. It could
be there is simply a higher correlation between the effectiveness of display
advertising and Visit Duration / Engagement than the effectiveness of
display advertising and Page Views / Consumption.

This could simply be because the panel measurement error, while high for
Duration, is even higher for Page Views - and probably getting worse.

Jim Novo
jim@...
Web Site: http://www.jimnovo.com
Blog: http://blog.jimnovo.com/