PPM produces listenership estimates that differ from diary based estimates–mostly lower estimates. Consequently, trending diary and PPM based numbers can produce misleading results and lead to erroneous conclusions.
Don’t take our word for it. This is what Arbitron has to say:
Different measurement methodologies can and do produce different results. We upgraded our measurement methodology, and the scale has changed accordingly.
We would think that “experts” who regularly deal with listening estimates would understand this, but apparently not. Interpublic’s Magna Global SVP Brian Wieser, who is the company’s Global Media Forecaster, recently generated headlines by noting that radio listening had dropped from 300 billion hours to 270 billion hours in 11 years.
The problem is that the comparison is meaningless.
He used RADAR estimates comparing the 1998 numbers to 2009 numbers. We suspect that most broadcasters don’t pay much attention to RADAR, and don’t know anything about it. But when any expert using any data declares radio on the ropes, it generates headlines.
Briefly, RADAR (Radio's All Dimension Audience Research) is a quarterly listenership survey done for national networks. RADAR was produced by Statistical Research Inc (SRI) until 2001, then sold to Arbitron. Arbitron has produced the estimates since. RADAR started out as a 12,000 respondent telephone survey. After Arbitron took over, it gradually became a diary survey, and now Arbitron combines diary and PPM data to create the estimates.
So Mr. Wieser is comparing 1998 estimates based on a telephone survey to 2009 estimates based on some amalgam of diary and PPM estimates. That’s a problem.
Arbitron says that different methodologies produce different results. Anyone old enough to remember when Birch competed with Arbitron knows that telephone estimates differ from diary estimates, and we’ve already seen how much lower PPM estimates are from diary estimates.
Mr. Wieser should understand this. He apparently doesn’t. The fact that he found only a 10% drop in total hours comparing 1998 telephone estimates to 2009 estimates with PPM in the nation’s top 10 markets is actually quite amazing.
It suggests that radio is considerably more resilient than its critics believe. It is further evidence that media consumption is not a zero-sum game and that new media consumption is not at radio’s expense.
Unfortunately, in our current environment no one wants to believe that. It is easier for Mr. Wieser to grab headlines by cooking up bogus trends that confirm the conventional wisdom.