Tag Archives: subject coding

HECoS, a new subject coding system for Higher Education

You may have missed that just before Christmas HECoS (the Higher Education Classification of Subjects) was announced. I worked a little on the project that lead up to this, along with colleagues in Cetis (who lead the project), Alan Paull Serices and Gill Ferrell, so I am especially pleased to see it come to fruition. I believe that as a flexible classification scheme built on semantic web / linked data principles it is a significant contribution to how we share data in HE.

HECoS was commissioned as part of the Higher Education Data & Information Improvement Programme (HEDIIP) in order to find a replacement to JACS, the subject coding scheme currently used in UK HE when information from different institutions needs to be classified by subject. When I was first approached by Gill Ferrell while she was working on a preliminary study of to determine if it needed changing, my initial response was that something which was much more in tune with semantic web principles would be very welcome (see the second part of this post that I wrote back in 2013). HECoS has been designed from the outset to be semantic web friendly. Also, one of the issues identified by the initial study was that aggregation of subjects was politically sensitive. For starters, the level of funding can depend on whether a subject is, for example, a STEM subject or not; but there are also factors of how universities as institutions are organised into departments/faculties/schools and how academics identify with disciplines. These lead to unnecessary difficulties in subject classification of courses: it is easy enough to decide whether a course is about ‘actuarial science’ but deciding whether ‘actuarial science’ should be grouped under ‘business studies’ or ‘mathematics’ is strongly context dependent. One of the decisions taken in designing HECoS was to separate the politics of how to aggregate subjects from the descriptions of those subjects and their more general relationships to each other. This is in marked contrast to JACS where the aggregation was baked into the very identifiers used. That is not to say that aggregation hierarchies aren’t important or won’t exist: they are, and they will, indeed there is already one for the purpose of displaying subjects for navigation, but they will be created through a governance process that can consider the politics involved separately from describing the subjects. This should make the subject classification terms more widely usable, allowing institutions and agencies who use it to build hierarchies for presentation and analysis that meet their own needs if these are different from those represented by the process responsible for the standard hierarchy. A more widely used classification scheme will have benefits for the information improvement envisaged by HEDIIP.

The next phase of HECoS will be about implementation and adoption, for example the creation of the governance processes detailed in the reports, moving HECoS up to proper 5-star linked data, help with migration from JACS to HECoS and so on. There’s a useful summary report on the HEDIIP site, and a spreadsheet of the coding system itself. There’s also still the development version Cetis used for consultation, which better represents its semantic webbiness but is non-definitive and temporary.

Heads up for HEDIIP

A while back I summarised the input about semantics and academic coding that Lorna and I had made on behalf of Cetis for a study on possible reforms to JACS, the Joint Academic Coding System. That study has now been published.

JACS is mainatained by HESA (the Higher Education Statistics Agency) and UCAS (Universities and Colleges Admissions Service) as a means of classifying UK University courses by subject; it is also used by a number of other organisations for classification of other resources, for example teaching and learning resources. The report (with appendices) considers the varying requirements and uses of subject coding in HE and sets out options for the development of a replacement for JACS.

Of course, this is all only of glancing interest, until you realise that stuff like Unistats and the Key Information Set (KIS) are powered by JACS.
– See more at Followers of the apocalypse

If you’re not sure why this should interest you (and yet for some reason have read this far) David Kernohan has written what I can only describe as an appreciation of the report, Hit the road JACS, from which the quote above is taken.

hediip_logoTo move forward from this and the other reports commissioned from the Redesigning the HE data landscape study, the Higher Education Data and Information Improvement Programme (HEDIIP) is being established to enhance the arrangements for the collection, sharing and dissemination of data and information about the HE system. Follow them on twitter.

On Semantics and the Joint Academic Coding System

Lorna and I recently contributed a study on possible reforms to JACS, a study which is part of a larger piece of work on Redesigning the HE data landscape. JACS, the Joint Academic Coding System, is mainatained by HESA (the Higher Education Statistics Agency) and UCAS (Universities and Colleges Admissions Service) as a means of classifying UK University courses by subject; it is also used by a number of other organisations for classification of other resources, for example teaching and learning resources. The study to which we were contributing our thoughts had already identified a problem with different people using JACS in different ways, which prompted the first part of this post. We were keen to promote technical changes to the way that JACS is managed that would make it easier for other people to use (and incidentally might help solve some of the problems in further developing JACS for use by HESA and UCAS), which are outline in the second part.

There’s nothing new here, I’m posting these thoughts here just so that they don’t get completely lost.

Subjects and disciplines in JACS

One of the issue identified with the use of JACS is that “although ostensibly believing themselves to be using a single system of classification, stakeholders are actually applying JACS for a variety of different purposes” including Universities who “often try to align JACS codes to their cost centres rather than adopting a strictly subject-based approach”. The cost centres in question are academic schools or departments, which are discipline based. This is problematic to the use of JACS to monitor which subjects are being learnt since the same subject may be taught in several departments. A good example of this is statistics, which is taught across many fields from Mathematics through to social sciences, but there are many other examples: languages taught in mediaeval studies and business translation courses, elements of computing taught in electronic engineering and computer science and so on. One approach would be to ignore the discipline dimension, to say the subject is the same regardless of the different disciplinary slants taken, that is to say statistics taught to mathematicians is the same as statistics taught to physicists is the same as statistics taught to social sciences. This may be true at a very superficial level, but obviously the relevance of theoretical versus practical elements will vary between those disciplines, as will the nature of the data to be analysed (typically a physicist will design an experiment to control each variable independently so as not to deal with multivariate data, this is not often possible in social sciences and so multivariate analysis is far more important). When it comes to teaching and learning resources something aimed at one discipline is likely to contain examples or use an approach not suited to others.

Perhaps more important is that academics identify with a discipline as being more than a collection of subjects being taught. It encapsulates a way of thinking, a framework for deciding on which problems are worth studying and a way of approaching these problems. A discipline is a community, and an academic who has grown up in a community will likely have acquired that community’s view of the subjects important to it. This should be taken into account when designing a coding scheme that is to be used by academics since any perception that the topic they teach is being placed under someone else’s discipline will be resisted as misrepresenting what is actually being taught, indeed as a threat to the integrity of the discipline.

More objectively, the case for different disciplinary slants on a problem space being important is demonstrated by the importance of multidisciplinary approaches to solving many problems. Both the reductionist approach of physics and the holistic approach of humanities and social sciences have their strengths, and it would be a shame if the distinction were lost.

The ideal coding scheme would be able to represent both the subject learnt and the discipline context in which it was learnt.

JACS and 5* data

Tim Berners-Lee suggested a 5 star deployment scheme for open data on the world wide web:
* make your stuff available on the Web (whatever format) under an open licence
** make it available as structured data (e.g., Excel instead of image scan of a table)
*** use non-proprietary formats (e.g., CSV instead of Excel)
**** use URIs to denote things, so that people can point at your stuff
**** link your data to other data to provide context

Currently JACS fails to meet the open licence requirement for 1-star data explicitly, but that seems to be a simple omission of a licensing statement that shows the intention that JACS should be freely available for others to use. It is important that this is fixed, but aside from this, JACS operates at about 3-star level. Assigning URIs to JACS subjects and providing useful information when someone accesses these URIs will allow JACS to be part of the web of linked open data. The benefits of linking data over the web include:

  • The identifiers are globally unique and unambiguous, they can be used in any system without fear of conflicting with other identifiers.
  • The subjects can be referenced globally by humans by from websites, emails, and by computer systems in/from data feeds and web applications.
  • The subjects can be used for semantic web approaches to representing ontologies, such as RDF.
  • These allow relationships such as subject hierarchies and relationships with other concepts (e.g. academic discipline) to be represented independently of the coding scheme used. An example of this is SKOS, see below.

In practical terms, implementing this would mean:

  • Devising a URI scheme. This could be as simple as adding the JACS codes to a suitable base URI. For example H713 could become http://id.jacs.ac.uk/H713
  • Setting up a web service to provide suitable information. Anyone connecting to that URL would be redirected to information that matched parameters in their request. A simple web browser would request an HTML page and so be redirected to http://id.jacs.ac.uk/H713.html; web applications would request data in a machine readable form such as xml, rdf or json.

The main overhead is in setting up, maintaining and managing the data provided by the web service, but Southampton University have already set one up for their own use. (The only problem with the Southampton service–and I believe Oxford have done something similar–is a lack of authority, i.e. it isn’t clear to other users whether the data from this service is authoritative, up to date, used under a correct license, sustainable.)


SKOS (Simple Knowledge Organization System) is a semantic web application of RDF which provides a model for expressing the basic structure and content of concept schemes such as thesauri, classification schemes, subject heading lists, taxonomies, folksonomies, and other similar types of controlled vocabulary. It allows for the description of a concept and the expression of the relationship betweens pairs of concepts. But first the concept must be identified as such, with a URI. For example:
jacs:H713 rdf:type skos:concept
In this example jacs: is shorthand for the JACS base URI, http://id.jacs.ac.uk/ as suggested above; rdf: and skos: are shorthand for the base URIs for RDF and SKOS. This triple says “The thing identified by http://id.jacs.ac.uk/H713 is a resource of type (as defined by RDF) concept (as defined by SKOS)”.

Other assertions can be made about the resource, e.g. the preferred label to be used for it and a scope note for it.
jacs:H713 skos:prefLabel “Production Processes”
jacs:H713 skos:scopeNote “The study of the principles of engineering as they apply to efficient application of production-line technology.”

Assuming the other JACS codes have been suitably identified, relationships between them can be described:
jacs:H713 skos:broader jacs:H710
jacs:H713 skos:related jacs:H830

Once JACS is on the semantic web relationships between the JACS subjects and things in other schemas can also be represented
http://example.org/123 dct:subject jacs:H713
(The resource identified by the URI http://example.org/123 is about the subject identified by jacs:H713).