During the 1980s, the Arbitron Company was developing the " Portable People Meter ", or " PPM ", technology to replace its self-administered, seven-day radio diary method to collect radio listening data from Arbitron survey participants.
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Rantel became an early evangelist for the new PPM method, because Rantel researchers had performed many audits of Arbitron radio diaries during its early years and were keenly aware of the weaknesses of the seven-day radio diary method.
