From A for AGF Videoforschung to Z for zapping, the most important technical terms in video research are explained here.

The 0/1 method is one of two processing methods which the user can select for special analyses in the AGF evaluation software. Under this method, performance values are calculated independently of the viewing duration. When a usage occurs, the p-value is set to 1. Thus, the full weight of a person is always included in the analysis. A prefilter can be integrated that limits the groups of persons to 60-second consecutive viewers.

4G refers to the fourth generation of mobile networks. The predecessors of the fourth generation were the first to third generations of mobile networks: 1G, 2G and 3G. Whereas 1G networks were still equipped with an analog transmission technology and only allowed for simple phone connections, 2G networks equipped with a digital transmission technology allow for a higher quality of phone connections at a lower cost and the transmission of SMS messages. GSM is the most widespread standard for 2G. 3G mobile networks allows for faster data transmission and support multimedia applications such as Mobile TV and Internet access. UMTS is the most widespread standard for 3G. Fourth-generation networks are IP-based and allow for high-speed data transfers at any time and place. LTE is the most widespread standard for 4G.

The newest generation of mobile networks allows for transmission speeds of up to 10 Gbit/s. 5G networks are currently being built out in Germany.

A-VoD stands for Advertiser-Supported Video-on-Demand, referring to video streaming services that are usually free of charge and contain commercial breaks.

Ad servers are used to distribute and process online advertising content. Ad servers directly send advertisements for online campaigns such as banners to an HTML page as soon as it is visited. Among other things the numbers of ad impressions and ad clicks are stored and made available to advertisers online.

Adjustment refers to a method for the artificial equalization of fluctuating data. The daily change of weight distribution in the AGF Panel (due to panel entries and exits, technical outages or structural changes) leads to a visible daily change of potentials for non-weighting characteristics. To avoid fluctuations of the target group potential within an analysis when performing multi-day evaluations, the target group is artificially adjusted in some analysis forms.

In both the Cumulation and frequency analysis and the Combination analysis, the weight distribution on the first day of the month of the first deadline for the programme list (campaign start) is applied for adjustment purposes.

The ADM Sampling System (Mastersample) is a sampling system created by the association of German market and social research institutions (Arbeitskreis deutscher Markt- und Sozialforschungsinstitute e.V., ADM) that is based on approximately 53,000 territorial units covering the entire territory of the Federal Republic of Germany. The method of a multi-stage stratified random sample of survey units used in the AGF Panel is based on the ADM Sampling System for Face-to-Face Surveys that has been used in the AGF Panel since July 1, 2005.

ADSL is an acronym that stands for Asymmetric Digital Subscriber Line. It refers to a variant of DSL as a broadband connection technology. Unlike DSL, data uploads to the Internet are transmitted at a slower speed than downloads from the Internet. ADSL can be used on both analog and digital telephone connections. In principle, an ADSL connection consists of two modems that are connected to a telephone line and connected with the computer by means of a USB interface or network card.

Advertisement refers to the form of advertising message: TV spot, advertisement, radio spot, movie theater spot, billboard, website online media.

Advertising medium refers to the medium used for advertising messages: television, print (magazine + newspaper), radio, movie theater, billboards and advertising pillars, online media.

The advertising medium contact for television is defined as contact with at least 60 consecutive seconds in an average half hour in which advertising appears.

The advertising medium contact for print media is defined as contact with an average issue in which advertising appears.

The advertising medium contact for radio is defined as contact with at least one quarter hour in an average hour in which advertising appears.

Advertising medium reach refers to the advertising reach of a medium. It is calculated on the basis of the definition of advertising medium contact. Under the agma guidelines, it is the currently valid standard of comparison for intermedia plans.

The Affinity Index indicates the size of reach in a certain target group in relation to the total viewership (market share in the target group as a percentage of the total market share). This index makes it possible to draw conclusions as to whether a given target group has watched a programme, commercial break or time slot more or less frequently than the total audience. For example, an Affinity Index of 140 means that the market share of a certain target group is 40% higher than that of the overall audience.

The ad customer subscription is addresses to media agencies and advertisers and permits the regular purchase of AGF data for the ad market. It is modular in structure and so allows the data purchase to be tailored for specific evaluation needs.

The AGF Conventions are the rules established by AGF for working with AGF’s complete research system. In particular, they regulate data charges and the rights and obligations for working with the data. The AGF Conventions are a binding component of all AGF’s contracts with third parties.

The AGF evaluation software fulfills the information and analysis needs of programming research and advertising planning. The software made available is sub-divided by functions into the reporting system VIDEOSCOPE, the planning system PLAN TV, the campaign control system TV CONTROL, and the special analysis system VIDEOSCOPE PLUS. AGF has engaged DAP GmbH to develop and maintain the evaluation software.

The "AGF GenZ Video Study" is a basic study on the use of video by children and young people between the ages of 3 and 17, which the Arbeitsgemeinschaft Videoforschung (AGF) commissioned from the market research institute Kantar in February and March 2020.

The study was structured in two stages: In a qualitative preliminary study, intensive explorations were conducted with children of different age groups (3-5 years / 6-10 years / 11-14 years / 15-17 years). The insights gained from these interviews on media use and the specific language worlds of the children could be implemented in the subsequent quantitative survey.

In the large-scale quantitative survey including daily routine surveys, consisting of more than 5,000 interviews and thus unique in this form on the German market, the children's TV and streaming use and their underlying motives were researched.

The central findings: Moving images are very popular with children and young people - 90 percent of all 3- to 17-year-olds consume videe content every day. You can find more information here.


The AGF Panel is one of the world’s biggest television panels, with 5,400 daily reporting, representatively selected households and the more than 11,000 persons who live in these households. Thus, it tracks the television usage of 75,304 million persons aged 3 and over or 38,773 million TV households whose MIE speaks German (01/01/2022). The usage of this universe is representatively tracked for both the entire Federal Republic of Germany and for the individual states of Germany. It is operated by GfK on behalf of AGF.

AGF Videoforschung has expanded the 2020 reach measurement with the "AGF Smart Meter" project: Using a measurement router technology developed by GfK on behalf of AGF, AGF records the use of streaming offers on smart TV sets in the AGF panel. This makes it possible to determine the average daily viewing time of selected video platforms such as Netflix and Amazon Prime Video on the big screen. The monthly reporting represents the usage times for currently seven target groups and is continuously being expanded. This measurement complements the measurement via TC UMX.

The AGF Video Potentials study is the external specifications study of AGF since 01/01/2022. The AGF Video Potentials is based on two separate research studies: The Potential Study, which is conducted in cooperation with agma and agof, and the AGF Platform Study. Both studies are conducted annually in two waves (spring and autumn).

After a joint weighting on the microcensus, both studies form the AGF Video Potentials, which (except for the Sky specifications) provides all relevant potentials of video image use in Germany and serves as an external specification for AGF research system.


Potential study: The potential study is conducted as a CATI survey (Computer Assisted Telephone Interview). People aged 14 and over are surveyed.

Platform study: The platform study is designed as a CAPI study (Computer Assisted Personal Interview) and is conducted at the respondents' homes. In addition to the survey, the interviewers examine TV-specific equipment features and check the reception options in the respondent households. People aged 14 and over are surveyed.

Before weighting on the microcensus, additional information on children aged 3-13 years is obtained from both studies and the specifications of the official statistics. The area statuses (municipality code, administrative district, federal state, GGK bik and GGK pol) of the survey studies and the microcensus are synchronised and - if necessary - updated.

In the joint weighting to the specifications of the microcensus, the tv-specific characteristics, which were obtained in the platform study by triage in the respondent households, are given a higher weight. All other information from the potential and platform study flows equally into the AGF Video Potentials.


The population comprises the resident population in the Federal Republic of Germany in private households with a German-speaking main income earner (HEB) and at least one device for moving image use (TV, PC, laptop, smartphone, tablet, game console) in use.


Total: 25,000 cases

Potential study: 20,000 cases, dual-frame, ADM selection basis, disproportional

Platform study: 5,000 cases, random sample, ADM face to face sampling system, proportional

AGF Videoforschung GmbH specializes in impartial video research. AGF continuously tracks the use of video content in Germany on a quantitative basis and analyses the data collected. It invests many millions of euros per year to continuously refine its instruments in order to deliver reliable data on the use of video content to the market on a daily basis. AGF consults closely with all market partners, including licensed TV stations, advertisers and media agencies.

The shareholders of AGF Videoforschung are ARD, Discovery Communications Deutschland, Mediengruppe RTL Deutschland, ProSiebenSat.1 Media SE, Sky Deutschland, Sport1, Tele 5, Viacom, WeltN24 and ZDF.

The research commissioned by AGF Videoforschung comprises the survey and reporting of the use of video content (TV and Online/mobile), irrespective of the distribution mode (e.g. linear or non-linear), time of use (e.g. live, time-shifted or time-independent), place of use (e.g. in the house or out of the house), distribution channel (e.g. IPTV, cable) as well as end device (e.g. TV, laptop or smartphone) as well as sender (e.g. TV broadcaster, telecommunication provider or Streaming provider) according to the rules and principles of market and opinion research.

AGF Videoforschung grants licenses for data use to other broadcasters, to media agencies and advertisers. Via licensed data users, it makes AGF data available to the press, production companies and sports sponsors in Germany and abroad, for example.

Aggregated data refers to the aggregation of individual values to form larger units, including the aggregation of second-by-second usage values for broadcasters measured to form longer time frames. The level of detail of the original information is therefore no longer included in the aggregated data.

agma is an acronym that stands for Arbeitsgemeinschaft Media-Analyse e. V., which is a coalition of advertisers, agencies and media formed with the goal of analyzing the performance of advertising media and the users of such media. For this purpose, agma conducts regular studies, so-called ma. The data collected in this study provides an important planning basis for the media genres of TV/radio, print, out of home and online. Among other things, the Potential Study conducted in collaboration with agma delivers results that AGF uses as part of its external specifications for social-demographic level control and for the weighting of the AGF Panel (see AGF Video Potentials). Within the scope of ma Intermedia PLuS, AGF provides data from its AGF Panel for intermedia planning.

Analog television refers to the analog transmission of TV programmes. In Germany, an analog television image transmitted at a frame rate of 50 Hz consists of a series of 25 individual images per second, which are further broken down into 625 lines. Images and sound are transmitted in wave form as multiple status signals. In Germany, analog television signals are only still transmitted via cable. Only digital signals are transmitted at the reception levels of terrestrial, satellite and IPTV.

Applications (apps) are additional applications that perform certain functions on terminal devices such as smartphones, tablets or a Smart TV. In the context of video usage, they especially include media libraries, EPGs, etc.

Audience flow is an indicator of the viewers’ loyalty to a programme. Studies of audience flows examine the identical viewership of consecutive programmes. They provide information about the proportion of the viewership of an examined programme that also watched the preceding programme or watched the subsequent programme.

Audio matching is a technical method for measuring audiovisual content. In the AGF Panel with the UMX measurement system, it has been used in the panel households since 08/01/2012 to survey the television usage of panel members. Under the audio matching method, audio signals in the television set are captured in the form of audio patterns and continuously checked against programmes stored in a server. Matching signals are then assigned to a TV broadcaster. If content cannot be clearly assigned to a broadcaster (for example, if the programme is broadcast simultaneously on several channels), additional information such as the regional reception spectrum or infrared codes are used to make the assignment.

AV source trackers serve the purpose of recognizing external devices that are typically used for television usage and are connected to the TV set. For example, DVD players and game consoles can be recognized by AV source trackers.

The average number of contacts indicates the average number of contacts per person; it is calculated as the quotient of contact total divided by market share. If the 0/1 method is used, this must be indicated.

Bandwidth refers to the range of a transmission channel that lies between the lowest and highest frequencies. Information is transmitted in this range via electronic signals. Higher bandwidth makes it possible to transmit a larger quantity of information.

The BIK municipality size classes are a model for classifying municipalities by the number of inhabitants in the respective BIK region (revised Boustedt Urban Regions Model, Boustedt Classes). They serve as the basis for stratifying the sampling system (ADM Sampling System) of GfK.

Blu-ray players are an advancement over DVD players. They are used to play film content on Blu-ray Discs, which can hold much larger quantities of data compared to DVDs and can therefore deliver higher-quality video and audio.

In television research, bouquets refer to package offerings composed of different programmes of a programming provider. The offerings are therefore marketed under one title.

Branded video players refer to an advertising form of non-linear video ads. They are characterized by the fact that the video is enclosed within a frame in which animations or banner ads are displayed. When users click on an ad in the frame, they can be sent directly to the advertiser’s page.

Break bumpers are three- to four-second inserts between ongoing programmes and commercial breaks. They are legally required and serve as an optical demarcation between programming and advertising.

The break number is a number assigned internally by the broadcaster to a commercial break. It is usually consecutive within an hour or a given environment. It is a component of the eight-digit commercial break code.

Broadband refers to the primary technology for accessing the Internet in Germany. Thanks to a relatively fast data transfer rate, connections are established much more quickly than via a modem.

The function of the broadcast master is to assign measured usage to broadcast elements such as programme, advertisement, etc. Components of the broadcast master include the programme directory, rate files and programme codes.

In the AGF system, the broadcasting day begins at 3:00 a.m. and lasts until 2:59 a.m. of the following day. All programmes during this time interval are assigned to the same calendar date. Under this definition, the data change occurs at 3:00 in the morning. This division of time, which differs from the customary calendar definition, has proved to be expedient for programme and advertisement planning by reason of viewer behavior. Among other things, this ensures that all data on TV usage during the previous television day can be retrieved at the same time during the night and reported in the morning.

In the AGF Panel, build-up refers to increasing the number of panel households. This is done to improve the validity of data at the regional level or to make more cases available for analyzing more deeply sub-divided target groups. In the AGF Panel, the evaluation quality of AGF data for smaller German states is ensured by regionally increasing the number of panel households (= disproportional build-up).

Customer variables (c-variables) are used in streaming measurement. They are maintained by the providers on a per-video basis. The information for each video usage is transmitted in the streaming measurement process. Like broadcaster protocols in TV, they serve the purpose of transmitting programme-specific information such as the video length or title or information on the matching of TV programmes (see Matching).

Cable refers to the transmission of analog or digital television via copper or fiber-optic cables. The cable section from the cable head station to the property usually belongs to a cable network operator. This section is referred to as Network Level 3. The distribution line from the property to the residence is owned by many small cable network operators such as building societies, but also by the network level 3 cable network operator. This section is referred to as Network Level 4.

Calibration is the term used by AGF to refer to the process of adapting the views and net coverage values in the weighted Video Streaming Panel to the level of the census measurement by means of statistical methods. Whereas the number of views is measured for the census measurement and the panel, the net coverage is only available in the panel and is extrapolated to the census level by means of a statistical estimation method.

In terms of the objective, calibration is similar to weighting: The purpose is to adapt the information collected from samples to the known external specifications of a full survey. In addition to the adjustment requirements dictated by the composition of the sample, calibration also serves to compensate for the design-related under-coverage of usage in the panel resulting from the non-coverage of at-work and other usage. The level variables of the census measurement only cover usage via the IP addresses assigned to Germany. To implement the calibration, the stream views must be aggregated to reach a sufficiently high number of cases case. These aggregations are known as calibration units. After the process of calculating the net coverage values at the level of the census measurement, these specifications are applied to generate a respondent-level data set, which forms the basis for analysis and planning.

Campaign control refers to the performance review of an already concluded advertising campaign on the basis of actually achieved reach values. It serves the purpose of measuring and evaluating the advertising impact.

Campaign planning involves the selection of suitable commercial breaks for the target group for an advertising campaign before they are broadcast. Suitable advertising environments are identified on the basis of past television data. The indicators that serve to forecast the performance of the planning campaign can then be calculated with the aid of planning software. The indicators are net coverageaverage contactsaffinityCPM-C (cost per mille contacts), CPM-U (cost per mille users), GRP and contact distribution.

CAPI is an acronym that stands for computer-assisted personal interview. CAPI surveys are computer-assisted face-to-face interviews in which the interviewer reads the questions directly from the computer screen and enters the answers into the computer. Unlike a traditional face-to-face interview, the questionnaire is stored in the computer instead of being printed out on paper.

Catch-up TV is a form of VoD in which broadcasters make TV programmes available to users on the Internet for a certain period of time after the original broadcast. These programmes can usually be accessed by users free of charge.

CATI is an acronym that stands for computer-assisted telephone interview. CATI surveys are computer-assisted telephone interviews in which the interviewer reads the questions directly from the computer screen and enters the answers into the computer in the telephone studio. Unlike a traditional telephone interview, the questionnaire is stored in the computer instead of being printed out on paper.

CAWI is an acronym that stands for computer-assisted web interview. CAWI surveys are computer-assisted online surveys in which the questions are displayed one after the other to the interviewee on the computer screen and the answers are entered into the computer and stored there. Unlike a traditional survey, the questionnaire is stored in the computer instead of being printed out on paper.

Cell plan refers to a plan of characteristics used for the level control and quality assurance of the AGF Panel. For each state of Germany, it defines 54 cells in the reception levels of cable and satellite and 27 cells for the levels of terrestrial and IPTV. It is therefore called the 54/27 cell plan. These cells are subject to continuous target-actual comparisons.