On Jun 21, 2010, at 6:57 AM, Chuck Geiger wrote: "The introduction of Arbitron 360 - Mobile monitoring device - What it means to you? The positives and negatives?"
It is a much-needed improvement which hopefully will increase the carry rate, especially early in the morning of women.
But, it doesn't address THE problems:
1) under-representation by a factor of two to four of cell phone only homes in the sample which necessitates HUGE weighting in almost every demo from month to month and
2) the fact that the sample simply must be at least four times larger in order to be truly statistically-reliable.
The diary sample has never been great, but at least in what Canadians call "BBM ballots" (diary survey = an election, a chance to vote for your favorites vs measurement of real usage) when you get a week with one household sending back one or even more diaries with 201+ quarter hours you know that home won't be in next week's sample.
In PPM, you will still live with homes like that for an average of seven months in the U.S. and at least a year in Canada.