New radio ratings system doesn't work

The Arbitron system for radio audience measurement - which is being trialled at the moment in London - appears to have acknowledged that it's having trouble reflecting actual audience figures:

The Arbitron chairman, president and chief executive officer, Steve Morris, said the company remained "confident in the audience estimates that the Portable People Meter [PPM] service is producing".

"However, over the past three weeks, feedback from our customers, the media rating council and other constituencies has led us to conclude that the radio industry would be better served if we were to delay further commercialisation of the PPM in order to address their issues," Morris added.

So, erm, it's confident that the system works, but needs time to... what, exactly? Either the system provides an accurate estimation of radio audiences, or it doesn't, surely?

And the chances are that it doesn't, as the sudden drop in audiences for black stations in New York suggested. Something that Morris tacitly accepts:

"We also plan to use the additional time to work closely with community leaders to review the workings of the Portable People Meter service and to gather their insights as to how we might improve compliance among persons 18 to 34, including young adults from ethnic minorities, across the diverse communities of New York, Los Angeles, Chicago and subsequent markets."

You'll notice the word "compliance" there, as if - somehow - black and Hispanic listeners aren't obeying the law by refusing to wear audience-measurement devices. Given that the members of the sample are doing the company a favour, Arbitron might find they have more success in their efforts if they stopped using "compliance" in favour of "assistance", "favours" or something similar.

It's still hard to understand how a company can admit that sizeable ethnic groups are, at best, under-represented in its sampling and yet remain "confident" in its audience figures. Arbitron - or just arbitrary?