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

Validity refers to the validity of a measurement method. It indicates whether and to what extent a method delivers error-free measurement. In the AGF system, the ECC is used as a validity check.

VAST is an acronym that stands for Digital Video Ad Serving Template. It refers to a template that allows for communication between a video player and an ad server. It was published by the Interactive Advertising Bureau (IAB).

VCR is an acronym that stands for Video Cassette Recorder, which is a device used for recording and playing back audio and video signals such as television programmes, for example. Programmes can be recorded to and played back from a video cassette at a later time, also on a different TV set.

VDSL is an acronym that stands for Very High Speed Digital Subscriber Line, a variant of DSL as a connection technology for broadband connections. This technology allows for considerably faster data transmission rates via cable networks than with DSL or ADSL.

Video content is programming or advertising content by which issues are reported, stories told or facts presented with cinematic techniques using video and audio. Video research involves the monitoring and reporting of video content usage. This can be done independently of the mode of distribution (e.g. linear or non-linear), time of use (e.g. live, non-live), place of use (e.g. in home or out of home), distribution channel (e.g. IPTV, cable or mobile) and terminal device (e.g. TV, laptop or smartphone), and also independently of the content provider (e.g. broadcaster, telecommunications provider or online video content provider).

Video streaming usage refers to the on-demand use of video content on a computer, another mobile device or IP-based services. It is an important component of video usage besides television usage.

The Video usage share is the share of the usage volume of an evaluation element in the usage volume of moving images as a whole. The basis for the video usage share are offers under AGF measurement. The fact is only available for the evaluation of convergence intervals.

VIDEOSCOPE was an evaluation software of AGF developed by DAP GmbH for the preparation of standardized evaluations of video usage. This software is a further development of TV Scope for the analysis of convergent usage data, which include both TV data and video streaming usage data (desktop and laptop). VIDEOSCOPE was succeeded by AGF SCOPE as the leading reference system on 08/01/2023.

VIDEOSCOPE PLUS was an extension of the AGF evaluation system VIDEOSCOPE that includes special analyses. This software allows for the detailed study of viewer growth, identities and movements across multiple TV programmes (audience flow, usage overlaps, etc.). The special analyses include cumulation and frequency analyses, identity analyses, origin and retention analyses, combination analyses and constellation analyses. VIDEOSCOPE PLUS was replaced by AGF SCOPE on 08/01/2023.

Viewers describe the users of an evaluation element (method 0/1) with a minimum usage condition of one minute consecutively.

The viewing duration indicates the duration of a person's usage of an evaluation element. While only the users within a target group are included in the calculation of the average duration, the entire target group (including non-users) is included in the calculation of the average viewing duration.

Viewing participation is the average usage of the evaluation element. It is calculated on an individual basis as the proportion of the duration of usage to the duration of the evaluation element.

The calculation of the average viewing participation of an evaluation element with more than one part or several evaluation elements with different lengths is only permissible if the length weighting is taken into account. The addition of viewing durations shall be marked as Contact total.

In cumulative counts and other special analyses, the calculation is designated as (cumulative) net viewing participation.

Viewing volume is the cumulative viewing duration in seconds.

VoD is an acronym that stands for Video on Demand, a service that makes it possible to access and watch a video from a selection of videos at any time.

VOSDAL is an acronym that stands for Viewing On Same Day As Live, referring to time-delayed usage.