Last week I explained how Arbitron measures radio listenership and produces ratings with the diary system. After years of criticism about the validity of data collected by diaries, they are being phased out in each market in favor of portable people meters (PPMs). The PPMs are beeper-like devises that pick up and record radio signals and transmit the data back to Arbitron on a daily basis when they are “docked.” Survey participants are required to carry them around everywhere they go, some up to 18 months. Meters must be worn on the outside of clothing and have motion sensors to detect movement (they can’t be stuck next to the radio all day on the dresser).
Whereas diary keepers were paid a few dollars per week, PPM carriers can earn more than a hundred dollars a month for each person in the household, depending on how much the motion sensors pick up movement. I read a recent independent research report from Broadcast Architecture that interviewed PPM panelists to get a feel for their habits. One women confided that her son tied the meter to a ceiling fan to get points (points are accumulated by motion and more points means more dollars).