It used to be simple. When Arthur Nielsen introduced his first metering device, the average American household had one television set and received three network telecasts. Today, the typical home has 109 channels, and our measurement technologies must evolve to keep pace with daily innovations in consumer electronics.
Meters & Diaries
Electronic metering technology is the heart of the Nielsen Media Research ratings process. We use two types of meters: Set meters capture what channel is being viewed, while People Meters add information about who is watching.
Diaries continue to be a valuable instrument in our measurement toolbox, and are used to collect viewing information from sample homes in almost every television market in the United States. Each year we process approximately 2 million paper diaries from households across the country for the months of November, February, May and July — also known as the “sweeps” rating periods. This local viewing information provides a basis for program scheduling and advertising decisions for local television stations, cable systems, and advertisers. In some of the larger markets, diaries provide viewer information for up to three additional “sweeps” months (October, January and March).
Over the course of a sweeps month, diaries are mailed to a new panel of homes each week. At the end of the month, all of the viewing data from the individual weeks is aggregated.
People Meter samples
Our national sample, composed of a cross-section of representative homes throughout the United States, is measured by People Meters, a technology that has been in place since 1987. These meters give us information about not only what is being viewed on the set, but also exactly which members of the household are watching.
The People Meter is a “box” — about the size of a paperback book — that's hooked up to each television set and is accompanied by a remote control unit. Each family member in a sample household is assigned a personal viewing button, which is matched to that person's age and sex. Whenever the TV is turned on, a light flashes on the meter, reminding viewers to press their assigned button and to indicate that they're watching television. Additional buttons on the People Meter enable guests who are also watching to participate in the sample by entering their age, sex and viewing status into the system.
In addition to our national measurement, Nielsen also measures some of the nation's largest local markets (such as New York, Los Angeles and Chicago) with Local People Meter Technology.
Set Meter samples
Large to mid-sized local markets (such as Seattle, San Antonio and Memphis) are measured by a different type of meter - one that gives information about set-tuning only. In these markets, demographic information is provided by a separate sample of people who fill out seven-day paper diaries (or eight-day diaries in homes with DVRs).
Diary samples
Smaller markets (such as Honolulu, Hawaii; Tallahassee-Thomasville, Fla., and Fargo-Valley City, N.D.) are measured by paper diaries only. These seven-day diaries (or eight-day diaries in homes with DVRs) are mailed to homes to keep a tally of what is watched on each television set and by whom.