• by Joe Mandese  @mp_joemandese, January 10, 2008

Following a series of unusual and surprising glitches in its highly redundant and supposedly fool-proof television coding system, Nielsen Media Research Wednesday sent letters to U.S. TV stations asking for help to ensure there are no more snafus.

"The purpose of this communication is to emphasize the importance of properly maintaining encoding equipment, which embeds codes in the audio and video streams at your station, and to review actions you can take to help ensure that you receive complete and proper credit for the tuning and viewing to your station," Nielsen said in the alert, which follows recent disclosures of several malfunctions, some of which have been attributed to problems at the TV station level.

Such problems were not supposed to occur, even if there were errors with the "active" coding at the station level, because Nielsen's so-called A/P (active/passive) codes also have a passive component. But in the most recent disclosure, three telecasts of New England Patriots games were understated for local TV stations in Boston and overstated for the ESPN cable network, due to a mix-up in the coding process (MediaDailyNews Jan. 9).

While such glitches are still considered rare, the revelations are troubling, because the A/P system was supposed to be Nielsen's solution to measuring television across digital TV platforms.

"As you know, Nielsen began deploying Active/Passive (A/P) meters in its local metered samples beginning in 2005. This is a critical quality initiative - A/P metering remains the most accurate technology available today for capturing all television viewing, including viewing to digital channels and time-shifted (DVR) viewing. Approximately 73% of our local market metered panel homes currently utilize A/P meters to credit audience," Nielsen advised stations in Wednesday's notice, stressing the need for "cooperation and active coding" by stations to ensure that the A/P system works properly.

"While Nielsen wants to work with you to minimize any such occurrence at your station in the future, it is ultimately your responsibility to encode properly," Nielsen emphasized.

Nielsen also circulated a "Guide to Encoder Best Practices" to stations, detailing proper coding procedures, a copy of which was not obtained by MDN.