The 'Cone of Input'

One of the main difficulties of using technology in teaching is the tendency for the features of the technology to determine the pedagogical features of the course. Or, to use the Japanese saying: when all you have is a hammer, everything looks like a nail. The ‘cone of input’ is an attempt to reassert the primacy of pedagogy in courses which use computer-mediated communication (CMC). An essential first step in the process of making a pedagogical judgement about which mix of technologies to use on a course is to find a ‘common denominator’ against which to assess the cost and value of each particular technology. The following quotation from “In Search of the Virtual Class” by Tiffin and Rajasingham (RKP, London, 1996) started the process off:
“For the moment, let us accept that the amount of bandwidth is a measure of the amount of information that can be transmitted at a given time by a channel …

“The irony of the current situation is that the classroom is a broadband environment and can be used to transmit as much information as the senses can absorb. Yet we mainly use it for learning with words which require little bandwidth.”

Thus ‘bandwidth’ could be a way of assessing one teaching ‘environment’ against another. The face-to-face (f2f) meetings represent, perhaps, the maximum use of bandwidth, with sensory contact possible, in addition to a very sophisticated use of sound and body language. An ISDN- or IP-based studio video conference represents a reduction in bandwidth use, although the amount of bandwidth ‘consumed’ is still great. Reduce the bandwidth still further and you have a podcast. A little more and you have a web page, an audio-blog, Internet radio, a text-based team blog, or an e-mail contact, until you arrive at one of the narrowest bandwidths, which is the signal sent down the printer cable which results in the paper copies of materials you might use. As can be seen in this diagram, the result is a cone inside which a teacher or tutor can make inputs into the students’ learning environment.

The point for the teacher using CMC is to design the course so that there is an optimal mix of bandwidth use to enable the students’ learning environment to be as rich during CMC as you hope it will be during f2f meetings (at which you have maximum bandwidth available). The aim is to provide inputs within the cone which will stimulate student learning both within and outside the cone, to produce what could be called ‘a cylinder of learning’. One example of this was provided on a local history course in an area of natural beauty in Hälsingland in the centre of Sweden. The teacher was on the way home one fine spring evening and took a digital photograph of a noted beauty spot from the window of the bus. Later that evening he published the blurred, but recognisable photograph on the course web site, with the question “Is this the soul of Hälsingland? “. Within 24 hours, each of the students had responded with opinions, stories of their own, poems, etc and had begun to respond to each other’s responses. The teacher’s role then was to guide and shape a dynamic process of learning (rather than having to try to start one off).

There is often a financial aspect to bandwidth use too: the more the bandwidth used, the more it costs (costs someone at least, since institutions and organisations often place the costs of certain types of bandwidth use, such as the hidden costs of maintaining lecture rooms, into general budgets, whilst other types, such as studio time in video conference studios, are often charged to a specific course budget).

The various types of bandwidth available have no intrinsic value – it all depends on what pedagogical value the teachers, students and course designers place on them. Thus, language teachers often need to ‘spend’ their bandwidth on confidence-building measures at f2f meetings, and sound files during the non-f2f aspects of the course. Biology teachers, on the other hand, might need very high-quality colour rendition for scientific photographs.

The connection between the type of learning stimulated by a particular type of bandwidth use may also not be obvious. Podcasts often seem to be intended to transmit information in a form the students have a certain amount of control over (stopping, re-winding, etc). However, the pedagogical value of the podcast may include their function of maintaining the feeling of belonging to the group, as the students hear the teacher’s voice at regular intervals and on important occasions as the course progresses.

The ‘Cone of Input’ concept was developed in the early 1990s as CMC first became viable as a teaching tool. It is true that technical possibility existed long before that, but it was at that time that students first gained access to the technology they needed to study – at least on a wide basis. As more and more technologies become available, the concept has stood the test of time. One of the most difficult aspects of the introduction of new technology into education is making a realistic assessment of the actual benefits to student learning gained from the time and money spent in introducing the latest technological development. Since you can potentially set a monetary value on bandwidth used, and couple this value to the cost and skills required to produce teaching inputs for each use of bandwidth, it is sometimes possible to introduce the technology very quickly.

An example of this was the introduction of podcasting into courses at Högskolan i Kalmar. The initial preparations took up, perhaps, ten working hours, and consisted of finding someone who could construct the .xml document which drives the podcasts, and learning in general how the process worked. We already had the programmes necessary to record the .mp3 files, and it quickly became clear that the incremental time required to copy files, amend .xml document etc, amounted to no more than 10 minutes per podcast, once we had done it the first time. Given the fact that a podcast should not be longer than about 15 minutes (because of downloading difficulties), the total ‘cost’ to the course budget is 25 minutes per podcast in production time. Preparation time is perhaps 10 minutes (because of a) the spontaneous nature of podcasting, and b) the fact that you’re talking about a subject which topical, since the course is on-going). Even if you made one podcast each week, throughout a 12 week course, you are only talking about adding something like 10 (clock) hours to your course time budget. When we began podcasting, it became clear what other use of bandwidth podcasting would replace … so in the end the cost of podcasting was neutral.

If you would like to discuss the Cone of Input further, and see its application to other types of course and technology, please do not hesitate to get in touch.

David Richardson
Högskolan i Kalmar
Sweden
david.richardson@hik.se