(6th in my logic of competence series)
In the earlier post on structure, I was looking for the structure of a single "definition" of "what is required". In following that line of enquiry, I drew attention to one of the UK National Occupational Standards (NOSs), in horticulture as it happened. Other UK NOSs share a similar structure, and each one of these could be seen as setting out a kind of relationship structure between competences in that occupational area. In each case we see an overall area (in the case cited, "production horticulture"), which is broken down into units, where each unit seems to correspond roughly to an occupational role -- one of a set of roles that could be distributed between employees. Then, each unit is broken down into what the person with that role has to be able to do, and what they need to know to provide a proper basis for that ability.
This is clearly a kind of tree structure, but it is not immediately obvious what kind of tree. Detailed consideration of a few examples is instructive. A first point to note is that NOS units may occur within several different occupational areas. This is particularly true of generic competences such as health and safety, but also applies to some specific units of skill and competence that just happen to play a part in several occupational areas, or several careers if you like. So, a particular unit does not necessarily have a single place on "the tree". A second point emerges from consideration of different trees. UK NOSs have a common structure of, roughly: responsible body (usually a Sector Skills Council); occupational area; unit; skill or knowledge. But this is not always the case with structures that are not NOSs. For example, the "Tuning" work on "educational structures in Europe" includes "generic competences" that are given just as headings, from "capacity for analysis and synthesis" to "will to succeed", and there is no attempt to break these down into smaller components.
Tuning's specific competences have the same depth of tree structure as their generic ones, still unlike NOSs. For instance, the "business-specific competences" have items such as "identify and operate adequate software", which looks a bit like some of the things that NOSs specify that people have to do, but also items such as "understand the principles of law and link them with business / management knowledge", which seems to correspond more with NOS knowledge items. Some Tuning items straddle both ability and knowledge. In all Tuning cases, the tree structure is shallower than for NOSs. You may find many other such tree-structures of competences, but I doubt you will find any reliable correspondence between the kinds of thing that appear at different points on different trees. This is a natural consequence of the logical premise of this whole series: that it is the claim and the requirement that are the logical starting point. Yes, we may well see correspondence at that level of job requirement, and much common practice; but any commonality here will not extend to other levels, because people analyse claims and requirements in their own different ways. It's not just that some trees leave out particular kinds of branch, but rather that, to go with the natural analogy, branches come in all thicknesses, with no clear dividing line between say a branch and a twig.
Even for the same subject area, there are quite different structures. As well as NOSs, the UK has what are called "subject benchmarks", which are more for academic courses rather than purely vocational ones. The QAA's Subject benchmark statement for "Agriculture, horticulture, forestry, food and consumer sciences" has this structure:
- 8 very general "abilities and skills", such as "understand the provisional nature of information and allow for competing and alternative explanations within their subject"
- other generic skills divided into
- intellectual skills
- practical skills
- numeracy skills
- communication skills
- information and communication technology (ICT) skills
- interpersonal/teamwork skills
- self-management and professional development skills
- "agriculture and horticulture",
- "the agricultural sciences",
- "food science and technology".
Both the subject-specific and the generic skills have descriptions for what is expected at three levels: "threshold", "typical", and "excellent". While this is an interesting and reasonable structure, the details of the structure do differ from the NOSs in the same area.
We have also to reckon with the fact that just about any of a tree's smallest branches can in principle be extended to even more detailed and smaller ones by adding thinner twigs. It might be tempting to try this with the Tuning competences, as talk about the "principles of law", and how they linked with other "knowledge", begs the question of what principles we are talking about and indeed how they are linked. However, in practice this is unlikely, because the Tuning work is intended as a synthesis and reference point for diverse academic objectives, and typically every academic institution will structure their own version of these competences in their own different ways. Another way in which two similar trees may differ is the number of intermediate layers, together with the branching factor. One tree may have twenty "thinner" branches coming off a "thicker" one; another tree may cover the same twenty by first having four divisions, each with five sub-divisions. There is no right or wrong here, just variants.
A simple way of representing many tree structures is to document the relationship between elements that are immediately larger and smaller, or broader and narrower. And recently, there seems to be a significant consensus building up that relationships from the SKOS Simple Knowledge Organization System are a good start, and may be the best known and most widely known relationships that fit. SKOS has the relationships "broader" and "narrower": the broader competence, skill, or knowledge is the one that covers a set of narrower ones. The only thing to be careful about is that the SKOS terms come from the librarian's BT and NT -- that is, if we write "A broader B" it does not mean "A is broader than B", but the opposite, that A is associated with a broader term, and that broader term is B. Thus B is a broader concept than A. Then, to use SKOS in the way it is designed to be used, we need identifiers for all the terms that might occur as "A" or "B" here. Each identifier would most reasonably be a URI, and needs to be clearly associated with its description.
This general purpose structure of URIs and SKOS relations seems to be sufficient to represent the basic aspects of most aspects of the competence structures I have mentioned or referred to, beyond the concepts and definitions themselves. We will next look at more advanced considerations.