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, time-shifted or time-independent), 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) in accordance with the rules and principles of market and opinion research.

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.

VIDEOSCOPE is 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 PLUS is 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.

Viewers refer to the potential of the users of a programme with a minimum usage condition of one minute consecutively according to the 0/1 method. Each person who exhibits an market share (i.e. p-value > 0) and fulfills the minimum usage condition of one second is counted and represented as a viewer of this programme.

Viewing duration refers to the average viewing duration of the reporting basis or target group per day. Whereas only users within a target group are included in the calculation of visit duration, the entire target group (including non-users) is included in the calculation of the viewing duration.

Viewing participation (VP) indicates the average number of persons of a target group who have watched TV. Each person is counted as the percentage of the programme duration represented by their viewing duration (PIN). This quotient of viewing duration divided by programme duration is multiplied by the weight per person to arrive at the individual viewing participation. The sum of all individual viewing participations of all persons is the average viewing participation of the programme.

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.