OClistener said:
thanks pjc1961 for the LA PPM analysis! Sorry new to this board, but does the P represent people. I presume then that people are keeping a record of what they listen to, right? I mean if not, how do they know how old their listeners are? If so, then technically the PPM numbers depend on who the diaries or people are recording, right? I always thought that they were just looking at the number of people who tune into their station.
PPM means Personal People Meter. There is a full description at
www.arbitron.com at the tabs for the PPM at the lower left.
In brief, Arbitron recruits a panel of households/families all members of which carry a small pager-sized device with them a minimum of 8 hours a day. The device "knows" what station each person with a meter hears and for how long they are exposed to it. The collected data is sent daily via a docking station that also recharges the meter.
The panel (a panel is a precise research term) is made up of a representative sample of the population of the market. That means if the market, in the case of LA is, 41% Hispanic, 41% of the people with meters will be Hispanic... or if 8% are teens, 8% of the people with meters will be carried by teens. There is one meter for about every 3,500 people in the market.
In a market with meters, there are no diaries. All measurement is passive, with no writing or remembering. Metered measurement is used in 48 of the top 50 markets now.
Arbitron processes the daily data and does a weekly report with limited age and gender breakouts, and then every 4 weeks, a full "book" with tens of thousands of ways of looking at the data by age, gender, ethnicity, geography, by dayparts, hours, half hours, quarter hours, etc. It's all done by projecting the sample into the universe to get
estimates of the listening characteristics of each station and the market.
