TV research Mediapulse measures digital TV from the screen. But there are other methods. An overview.
Mediapulse, the foundation for radio and TV research that has been active for a year, is gearing up for the digital future and must therefore decide on a measurement method. Firstly, it installs stationary measuring instruments in the TV sets of panel households, which can recognize the channels switched on using frequencies, codes and electrical voltage. The second form of measurement is carried out using mobile devices (small box or wristwatch) worn by the panelists. The built-in microphones pick up ambient noise, including radio and TV sound, and reduce it to codes (audio matching). In a control center, the same is done with all available programs. The codes of the measuring devices are then compared with those of the control center, allowing the programs used to be identified. The Radiocontrol clock, which is used in Switzerland for radio and sometimes also for TV measurement, works according to this method.
Digital technology per se does not pose a fundamental problem for either form of measurement. However, since the technology has many different standards, it also makes new forms of use and offerings possible and the number of receivable programs is increasing exponentially, new solutions are needed, of which the five most important methods are presented here.
Audio matchingSome places rely entirely on audio matching (as described above). However, this requires huge computer capacities at the headquarters in order to record, encode and compare hundreds of available stations with the measurement data. For comparison: Mediapulse currently records around 180 radio and TV stations using this method.
CodingIn the second approach, the measuring device manufacturers agree with the individual TV broadcasters that, in addition to their digital signal, they will also transmit an individual code that is inaudible to the human ear (= coding). This then enables the measuring device to make the correct assignment.
InterfaceA third way is via the set-top boxes that every household needs for digital reception. These boxes are very different. However, with individually developed and subsequently installed software (= interface), the channels can be correctly assigned. Mediapulse has also previously used this solution for TV research.
SIPA fourth approach, now chosen by Mediapulse (see page 1), focuses on the screen: Only what appears there is recorded. For this purpose, the measuring box in the household is equipped with Screen Interface Processing (= SIP). SIP is a kind of scanner that - invisible to TV viewers - scans the screen second by second for information such as channel number, channel logo and other information and saves it.
SubstitutionThe fifth option is to consider a radical solution: instead of installing just a single measuring device in the panel household, almost the entire existing TV set is replaced (= substitution). Only the screen and any existing video recorder remain, but the set-top box, hard disk recorder (PVR) or DVD player (if present) are removed and replaced by other devices. Although these fulfill the same function, they are equipped with measurement technology and storage media. This allows the TV behavior of the panelists to be studied in even greater detail, right down to the volume, brightness or color tone settings on the remote control. The favorites list can also be viewed.
Possibilities and limitationsAll of these approaches have their advantages and disadvantages. The disadvantages include the costs, which are of course particularly high in the case of device substitution. However, there are also scientific concerns about substitution: it may represent too strong an intervention and could influence the panelists' behavior instead of simply measuring it.
For the coding and interface variants, on the other hand, the measuring device manufacturers are dependent on the cooperation of the TV broadcasters or set-top box manufacturers. However, this help is sometimes difficult or impossible to obtain, especially from box manufacturers and broadcasters abroad. Those who choose these approaches therefore usually have to decide which programs they want to measure and which not. However, this also means giving up the claim to measure all TV consumption as far as possible.
The same applies to audio matching, but here the scope is limited by computer capacity. However, the method also has significant advantages: TV consumption can be measured more individually than with any other approach. TV usage outside the home can also be included.
That leaves SIP, which, like audio matching, works independently of TV channels, set-top box manufacturers and reception type, but also knows no capacity limits. The only effort required is the coordination with the range of programs available in the panel household. As SIP monitors what is happening on the screen, it can be used to measure not only live TV usage, but also time-shifted television using video recording, video on demand, DVD or PVR. This is because the channel information reappears on the screen when recorded TV programs are played back. The SIP can therefore read it in again and assign it to the original broadcasts.
If panelists view private video or DigiCam recordings on the screen, this is also recognized, partly because channel information is missing.
Several methods usedWhich of the approaches described are used depends on the measuring device manufacturers. Some also combine several variants. The Swiss Telecontrol Group, for example, which is part of the German GfK Group and also supplies the measuring devices for Mediapulse's Swiss TV panel, primarily relied on the interface variant until two years ago. Telecontrol VIII, the latest generation of measuring boxes, can also "read" around 30 set-top boxes.
"For around a year now, however, these boxes can also be equipped with SIP. Austria, for example, has been using devices with SIP since the end of 2007," says Matthias Steinmann, founder and CEO of the Telecontrol Group Telecontrol also works with the substitution method. "At the request of the Arbeitsgemeinschaft Fernsehforschung (AGF), the German equivalent of Mediapulse, we developed the TCScore system, which largely replaces the TV set in the panel household," says Steinmann. AGF has ordered 9,000 such TCScore substitution sets at a cost of 19 million euros. 30 test households are currently under observation. Austria has also ordered 600 TCScores, which corresponds to half of the TV panel there.
However, it is clear that even with these technologies, not all forms of usage can be measured. For example, mobile TV, streaming (Internet TV on a PC) or downloads on an iPod are not yet recorded. But according to Steinmann, Telecontrol already offers solutions for these areas too.
Markus Knöpfli
Need for clarificationWhatever TV research can measure - it cannot limit itself to the search for suitable instruments and measurement methods, but must also help to clarify at least three other fundamental questions. Namely: Should everything that is broadcast and used also be measured?
Where are the limits to measurement technology - financial and otherwise? And with regard to time-shifted television, it must be agreed (as is already the case today with repeat programs) when a program is considered to have been viewed. Only when broadcast and consumption take place simultaneously (live)? Or also when parts of it have already been used an hour earlier via cell phone? Is only what is seen on the same day counted? And how do you count what is only watched tomorrow or in a week's time? (mk)
No big differenceLike SRG, ORF in Austria also switched the terrestrial transmission of its TV signals from analog to digital (DVB-T) last year. This affected around 30 percent of all TV households, almost all of which have since switched to digital reception. GfK Austria, which is responsible for the TV panel there, has been measuring all households with digital TV using SIP since the beginning of 2008. There are no figures yet. However, TV research manager Alke Sulimma has not noticed any significant change in behavior. "Despite the greater choice now available, daily TV viewing time is trending downwards," she says. Sulimma can only speculate about the reasons at present. (mk)