The LA Times.
Last month, Nielsen discovered that a high-ranking Univision Radio programming executive at the company's Los Angeles station, KSCA 101.9 FM, had access to several of Nielsen's portable people meter devices that pick up audio signals. Nielsen uses data transmitted from the devices to determine which radio stations have the most listeners.
It is a violation of Nielsen rules for a station employee to have access to the devices. Univision quickly fired the executive and announced more rigorous ethics training sessions for its employees. No other station executives were reprimanded.
Nielsen notified radio stations on Wednesday that despite the problems it found with two households that were removed from its sample audience in Los Angeles, the agency would not go back and reissue the ratings for last year or the first quarter of 2014.
"The analysis revealed that significant differences in the estimates from April 2013 to March 2014 were isolated primarily to a single [Univision] station ... and that there were minimal differences in the estimates for the overwhelming majority of other stations in the market," Nielsen said in a memo sent to L.A. radio stations that was reviewed by The Times.
For the other stations, "we found that 98.8% of the records had less than a 5% difference between the originally published" data.
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