"I don't think they're that useful because stations could start distorting ratings with promotions," notes Agresti. "Weekly ratings give radio stations the option to do that during key retail weeks and massively inflate their numbers."
Although Arbitron is promising a nationwide rollout in the future, the ratings company is vague on the time frame and the cities targeted.
To date, Arbitron has only offered monthly ratings. The introduction of weekly PPM ratings appears to suggest greater transparency at a time when accountability and flexibility are keywords in the media-buying community. But the new level of precision may prove to be a double-edged sword.
According to Agresti, the sample sizes seem to be getting smaller--"and the smaller the measurement pool is, the greater any distortion is going to be." She doesn't see buyers wanting to look "that closely," although she concedes that weekly ratings might be useful to some local retail accounts.
Indeed, in promoting the new service, Arbitron identified local retailers and radio promotions as key areas where the weekly ratings could help local programmers. Gary Marince, Arbitron's vice president of programming services and development, said in a statement: "With PPM, when you run a strong promotion, make a personality or format change, you'll have credible audience feedback within weeks." It's unclear, however, whether this would benefit media buyers.