A. C. Nielsen Co. is expected to reveal plans in Los Angeles today to more accurately measure the size and makeup of audiences watching national network and cable-TV programming.
In a marked break with its past practices, the ratings company is expected to announce that it gradually will adopt a new ratings technology to measure the individual viewing of TV programs rather than aggregate household tune-in patterns.
As part of the new system, Nielsen plans eventually to increase the size of its national sample of electronically surveyed homes to 6,000 from the current 1,700.
The company said that the new system could cut in half its standard margin of error in national TV ratings.
Full implementation of the new ratings system is planned for September, 1988, said Nielsen spokesman Larry Frerk. Details of the new system are expected to be unveiled at a meeting of Nielsen's clients this morning at the Century Plaza Hotel in Century City.
According to Frerk, the new technology, called "people meters," will enable the ratings service to produce more detailed demographic profiles of viewers of TV programs and to more accurately determine the size of audiences tuned to cable-TV program services.
Frerk said that the people meters are being introduced as a result of improvements in audience measurement technology as well as the desire of programmers and advertisers to better gauge the audiences of national program services that did not exist just a few years ago.
The ratings firm plans to introduce the first 1,000 people meters by the fall of 1986, replacing written ratings diaries currently used to supplement about 1,700 homes around the country equipped with passive electronic ratings meters.