"A" Counties – The classification of counties based on Census household counts and metropolitan proximity. "A" counties are highly urbanized areas and belong to the 21 largest Metropolitan Statistical Areas. The combined counties contain 40% of the United States households.

AAAA (American Association of Advertising Agencies) – An organization representing the interests of advertising agencies.

AAF (American Advertising Federation) – An association that advocates the rights of advertisers. Based in Washington, the AAF is a grass-roots organization with chapters in most U.S. cities. The AAF Foundation supports educational programs and minority group employment initiatives.

Above-the-Line Costs – Production costs related to story and script, producer, director and stars. The program's other costs are "below-the-line."

Ace Awards – Annual awards by the National Cable Television Assn. In recognition of outstanding achievement in programs for cable television. Initiated in 1979.

Across the Board – A "board" being a week; a program or commercial announcement scheduled at the same time on successive days of the week.

Address – An Internet term. There are two types of addresses: E-mail addresses are for sending e-mail to someone; they almost always contain an @ symbol between the individual's name and the domain name. Web page addresses are more properly called URLs.

Addressability – Remote control function of sophisticated equipment that allows a cable operator to activate, disconnect or unscramble the signal received by a subscriber. Also called Addressable Cable Converters.

Ad Hoc Network – A temporary grouping of stations to carry a specific program.

Adjacencies – Commercial announcements which are next to, or adjacent to, a program rather than in breaks within the main body of the program.

Ad*Sentry - Ad*Sentry is a web-based tool from Nielsen Monitor-Plus that identifies new TV spots within 48 hours of the first airing, providing digital images in full color and audio.  Clients select specifications by advertiser, brand, or category, and are immediately alerted via email when a new creative is identified. Ad*Sentry reports occurrence data for each creative by market, distributor, date/time, and commercial duration. More about Ad*Sentry on our Monitor-Plus site

Advances – The local audience ratings estimates available just before receipt of the printed local ratings report.

Advertising Agency – An organization acting as an agent for a producer of goods or services (an advertiser) devoted to developing and placing advertising in order to further the acceptance of a brand product, service, or idea.

Advertising Research Foundation (ARF) – Founded in 1936 by the Association of National Advertisers and the American Association of Advertising Agencies, the ARF’s mission is to improve the practice of advertising, marketing and media research. It is located in New York.

Ad*Views - Ad*Views, Monitor-Plus' flagship product, provides summarized and detailed advertising intelligence across 16 media. Ad*Views delivers competitive information in standard report layouts, customized layouts and offers many exclusive functions for advanced competitive analyses. A few of the capabilities includes: details on promotional activity, digital snapshots of all creative executions, trending of ad dollars for any of the 210 U.S. markets, and share of business reports. Ad*Views tracks and analyzes commercial units, GRPs, and dollars in a single, easy-to-use system. More about Ad*Views on our Monitor-Plus site

Affidavit – A document used in commercial television stating that a commercial or program ran as ordered.

Affiliate – A broadcast station not owned by a network but airing its programs and commercials.

Alternate Delivery Source (ADS) The technologies included in alternate delivery sources are satellite (C-Band), DBS (KU-Band), SMATV (Master Antennae) and MMDS (includes Multi-channel multi-point and multi-point distribution service). 

AM/FM – See Modulation

American Women in Radio and Television (AWRT) – A national, non-profit organization dedicated to advancing women in the electronic media and related fields. Established in 1951, AWRT has local chapters throughout the U.S.

AMOL – See Automated Measurement of Lineups.

Amplifier – Electronic device used to boost, or amplify, electrical signals. In cable systems, amplifiers are used to strengthen TV signals distributed by coaxial cable.

ANA (Association of National Advertisers) – Established in 1910 to represent the interests of advertisers.

Analog – A continuous electronic signal that carries information in the form of variable physical values, such as amplitude or frequency modulation (AM or FM); unlike digital signals which are made up of discrete pulses.

Ancillary Markets – Secondary sales targets for a program that has completed its first run(s) on its initial delivery medium.

Andy Awards – Awards for print and broadcast creativity given by the Advertising Club of New York.

ANIK – Canadian broadcast satellite.

Antenna – A metallic device such as a rod or wire used for radiating or receiving TV or radio signals through the air.

Anti-Leap Frogging - A former FCC requirement that cable systems importing distant signals select those broadcast stations originating in outside markets that are closest to the cable system's community.

Area Probability Sample – A type of a probability sample. The initial sampling units are well defined geographic areas, and ultimately housing units. (See also, Probability Sample.)

ARPANET – A computer network developed by the U.S. Department of Defense during the Cold War, it later became the basis of the Internet. Designed to survive nuclear attacks, ARPANET was distributed over a large number of geographically dispersed computers so that, even if most servers were destroyed, the remaining servers would be able to communicate.

Aspect Ratio - The ratio of a screen's width to its height. Today's TV screens have a 4x3 ratio. In the digital television environment, TV screens may have ratios as high as 19x6.

Association of Independent Television Stations (INTV) – Association that represents the interests of independent television stations in regulatory and promotional concerns. It is based in Washington, DC.

Attrition – The loss of respondents from a research panel. Panel members may drop out voluntarily or be asked to leave. The attrition rate usually is expressed as a percentage of the ongoing panel for one year.

Audience – A group of households or individuals who are attending, listening or watching something. It is often used to indicate viewers of a television program or another advertising medium. Audience measurements are expressed as percentages, or as estimated numbers of households or individuals watching or listening to a program.

Audience Composition – Estimates of numbers of people viewing a program or time period, by age, sex, etc.

Audience Duplication – The number or percent of households or individuals reached by one program (or station) that are also reached by another program (or station).

Audience Flow – A measure of the change in audience during and between programs. Audience flow shows the percentages of people or households who turn on or off a program, switch to or from another channel, or remain on the same channel as the previous program.


Audilog – An early version of the paper diary used by Nielsen Media Research to gather demographic data from households in its national sample. Audilogs were introduced in 1953, and placed in sample homes already equipped with Recordimeters. These meters verified the accuracy and completeness of the diary entries by automatically recording total minutes of TV usage daily. The Recordimeter’s presence, usually on top of the TV, also reminded households to write down viewing information in the diary. Nielsen Media Research no longer uses the combination of meter and diary measurement devices in the same panel.

Audience Turnover – The ratio of cumulative to average quarter-hour audiences. Turnover is a valuable index of the consistency of an audience. If turnover equals 1.0, all the station’s audience for a given time period or daypart is tuned in during the average quarter hour of the daypart. If turnover equals 2.0, there are twice as many persons in the cume audience of the daypart as in the quarter hour.

Automated Measurement of Lineups (AMOL) – An electronic identification method used by Nielsen Media Research to decipher codes each broadcast/cable network or other program supplier assigns to their programs before distribution to a station or cable system.

Audimeter – An electronic meter, attached to the television set, which measures channel, time and duration of tuning. The early Audimeters, adapted from the radio Audimeters, contained tapes or cartridges which were mailed back to Nielsen Media Research every week by the sample home. Weekly ratings were reported. The next generation of Audimeter was called the "Instantaneous Audimeter," and it required no interaction from the household. It collected the set-tuning data on a minute-by-minute basis and fed the information instantaneously to Nielsen Media Research via a dedicated phone line in the home. Unlike later models, the "Instantaneous Audimeter" had no storage capacity, so data were transmitted "live" to Nielsen Media computers for processing. Beginning with the 1973 television season, Nielsen Media Research introduced the "Storage Instantaneous Audimeter" for nationwide service. The new Audimeter automatically recorded and stored minute-by-minute tuning records for channel, time of day, and duration of tuning. Now the data could be stored and automatically retrieved quickly by Nielsen’s computers via a separate phone line from the home during the night. This resulted in faster service and made possible the introduction of a daily national ratings report which included average audience, share, station count and evening network coverage. (Nielsen Media Research started to discontinue separate phone lines from sample homes in 1982, relying instead on the single home phone line.)

Audio – The sound portion of a television or radio broadcast signal.

Availability – Time on a station, cable channel or network which is offered for sale.  Also know as an Avail.

Avail – see Availability.

Average – A statistical measure. The most common average is arithmetic mean. This is computed by adding a group of values together and dividing by the total number of values in the group.

Average Audience (AA) – A widely used rating term, expressed as a percentage, to reflect viewing to the average minute of a program or time period. It is an average of the audience at minute 1, 2, 3, etc. As such, it serves as an estimate of the average commercial audience (households or persons).

Average Episodes Per Viewing Household/Person – The average number of quarter-hours viewed by each household/person reached.

Average Frequency – The average number of times households or persons viewed a given program, station or advertisement during a specific time period. This number is derived by dividing the Gross Ratings Points (GRPs) by the total non-duplicated audience (cume). For example, if a group of programs has achieved 30 GRPs and a cume of 20, then the average frequency is 1.5 exposures per person or household. The term is interchangeable with frequency.

Average Hours – The average number of hours viewed per TV household, per day, per week, or per time period.

Average Quarter Hour (AQH) – The number of persons or households estimated to be tuned to a specific channel or program for at least five minutes during an average fifteen minute period.

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