Docbook is the older of the two specifications and created specifically for technical documentation. DITA, is a younger specification which grew out of IBM, and is referred to as having its own architecture and was designed to provide structure to more than just a book. Both specifications are OASIS standards.



As with XML schemas, both specifications can be extended to include bespoke features. However, Docbook is based more on a book structure with Sections and subsections, where as DITA is built around topics that can be built up in any arrangement based on a document map.  A DITA topic is open to specialisation itself, however, a topic has only three required elements

1. An id attribute
2. A title
3. A body

A topic can exist as a single XML file which can be composed into any arrangement for publication through the use of a document map. A DITA structure would present a more flexible architecture where the same “topic”, i.e a journal article section, such as an abstract, materials and methods, or results, could be included with ease more than one publication, correctly referenced. In this respect DITA is more like an object-oriented document schema, and can be more easily repurposed (in terms of structure) for any output format (i.e pdf, HTML). In the same respect, Docbook can be configured with some work to behave on a more topic by topic basis and DITA can support a book based methodology. They are after all both XML schemas and are equally extensible or open to specialisation.

As its a standard, whole ecosystems have emerged which makes use of the DITA architecture. For example, DITA for publishers provides libraries to convert DITA markup into HTML, PDF, EPUB, and Kindle rendering support. This allows content structures in DITA to be repurposed for different audiences or different devices with relative ease.

I have recently started using DITA as an architecture to represent content, primarily designed for books. However, with new demands appearing for different delivery mechanisms of the traditional textbook, such as Web delivery and ebooks, DITA is proving to be immensely powerful to deliver the same content through different mediums with relative ease and speed. In using it, it seems obvious that a DITA architecture would benefit the representation of content within a journal article, allowing references re-purposing and multiple format delivery. Maybe a topic for discussion through the Beyond the PDF forum.

In the end, it’s just XML, so I wont repeat the virtues of content markup through XML. However, for me its main advantage is the object oriented -like topic structure as a working architecture.

Related articles

• Using RDFa with DITA and DocBook (devx.com)
• Dita Educational Use cases (docs.oasis-open.org)
• Converting documents between a wiki and Word, XML, FrameMaker or other help formats (ffeathers.wordpress.com)
• Future-proofing e-books with XML (teleread.com)
• The PDF Landscape for DITA Content (tc.eserver.org)

On looking at the date on my last post, shamefully I realised I have not posted for over a year. Most, well all, of my activity has been via twitter and FriendFeed. The reason for the lack of posts is also related to why I started bloging in the first place. I created this blog when I was a Phd student and maintained it while I was a postdoc to discuss work, ideas and problems. With my move to the biotech industry I was not able to post so freely on work related issues.

I have now moved from being in the biotech industry to the publishing industry (see About page) and I think I am in a position to blog a bit more freely than I have been previously. So with this in mind I have been doing some housekeeping. I have updated my about page accordingly. I have updated my publication page via referencing my Mendeley public profile, as opposed to referencing my CiteULike profile.

However, the main change is that I have retired the “peanutbutter” meme  (hence the title for this post) and replaced it with fgibson.com (the jam). Hopefully wordpress will work its magic and maintain the mapping for all the subscriptions, but just incase, if you want to, please update your feed subscriptions to http://www.fgibson.com

Maybe my top referring search term “is peanutbutter good for you health” will start to be replaced with more informatics relevant topics.

This is a cross-posted , two-author item available both from this and Allyson’s blog.

Often the words “attribution” and “citation” are used interchangeably. However, in the context of ensuring your work gets the referencing it deserves when others make use of it, it is important that the differences between these two concepts are clear. This article outlines the differences between attribution and citation, and suggests that what most scientists are interested in is not attribution, which can be ensured via licensing restrictions, but instead citation, which is a much tougher nut to crack.

At ISMB last week, there were a number of conversations about the difference between attribution and citation. This topic was brought up again yesterday in a conversation between the two authors of this post, Frank and Allyson. It is an important distinction which is explored in this post.

First, some definitions for attribution and citation. These are not the only definitions possible, but for the purposes of this discussion, please keep these in mind.

Attribution: Acknowledgement of the use of someone else’s information, data, or other work. Crucially, while Wikipedia has a fairly straightforward definition of citation, it does NOT mention even common ways that attribution should be implemented (see Wikipedia attribution page).

Citation: When you publish a paper that makes use of someone else’s information (data, ontology, etc.), you include in that paper a reference to the work of that other person or group. Wikipedia states that it is a “reference to a published or unpublished source” whose prime purpose is of “intellectual honesty”.

Distinguishing between attribution and citation.
You can imagine that citation is a specific type of attribution, but attribution itself can be performed in any number of ways. For scientists, citation is much more useful to their careers as a result of the publish or perish environment.

So, what could attribution consist of? First, let’s take as an example the re-use of someone else’s ontology or specific sub-parts or classes of that ontology. Each class in an ontology is identified by a URI. Therefore, is importing the URI enough? With a URI is it clear where you got the class from? If it’s not enough, where do you put that reference or statement that you are re-using other classes: within the overall metadata of your own ontology? Alternatively, when attributing data is a reference to the originating paper or URL from where you downloaded the data enough? Where do you put that reference: within the metadata of your own document? As a citation? How much is enough attribution?

These questions cannot easily be answered.

A common-sense answer to the question of properly fulfilling requirements is to, at a minimum, first cite their information in your paper, and second include URL(s)/URI(s) in your metadata. But here we get to the crux of the matter: we’ve now stated that a useful way to ensure attribution is to cite the other person. But, if you think carefully, what’s more important for your impact assessments, and your work? It’s actually the citation itself. Sure, acknowledgement via extra referencing in the metadata of the person using your information is great, but what you really need is a citation in their work. If we aren’t careful, we will all make the easy mistake of conflating citation in papers with importing a licensed piece of information and how to mark its inclusion: the former is what we often are scored on and what we would really like, while the latter is the only thing a license enforces. Licensing with attribution requirements is not citation; you can make use of a licensed ontology, but this does not require you to cite it in a paper.

Attribution: the legal entity.

Important point: It’s easy to use a license such as the CC-BY, thinking that you’ll ensure citation, when in fact all you’re doing is ensuring attribution.

What are the implications of attribution? It can quickly get out-of-control and difficult to manage.
By requiring attribution in an ontology or data file, if someone imports information (such as a class from an ontology) into their own document, the new one must attribute the original. Continuing the ontology analogy, if there are 20-30 ontologies being used for a single project (which is not inconceivable in the coming years), there could be great difficulty in maintaining attribution for them all.

Important point: While licenses such as the CC-BY allow the attribution to be performed “in the manner specified by the author or licensor”, this could lead to 30 different licensors requiring potentially 30 different methods of attribution, and attribution stacking isn’t pretty.

Citation: the gentlemen’s club.

Can citation be assured? No. Well, maybe.
You can imagine citation as a gentlemen’s club, as propriety dictates that you should cite another’s work that you use, but there is no legal requirement to do so. Indeed, many believe that citation should not be enforced anyway. In contrast, attribution as required by licenses is a legal statement. However, let’s revisit the clause in CC-BY that states the author/licensor can specify the manner in which the attribution is given.

Important point: Could you use a license such as CC-BY, and state that the attribution must come in the form of, at a minimum, citation in the paper which describes the work being performed by the licensee?

Bottom line: which one is more important to you, as a scientist? Depends on the context.
This is difficult to answer. There aren’t very many guidelines available for us to analyse. The OBO Foundry does have a set of principles, the first of which states that “their [the ontology(ies) and their classes] original source is always credited and that after any external alterations, they must never be redistributed under the same name or with the same identifiers”. However, how this credit is attained is unclear, as described in various blog posts (Allyson, Frank, Melanie). As a result, the following conclusions came out of the OBO Foundry workshop this summer (Monday outcomes): it is “unclear if each ontology should develop their own bespoke license or use develop ‘CC-by’; how to give attribution? Generally use own judgment, here MIREOT mechanism can help when importing external terms into an ontology, giving class level attribution” (MIREOT web page, see also OWLED 2008 paper). Therefore, while they are aware of the problem, they don’t offer a consensus solution(s).

The flipside of this is that in order to use an ontology, you first have to write a paper and cite the classes you wish to import, then get on with the work. If you never get a paper and therefore a citation, is you ontology/data illegal? If you take the example of OBI, which imports several other ontologies and is an open community of developers, would a license restriction requiring citation actually prevent the work starting? This is probably a bit of a chicken-and-egg scenario, if it were ever to come a reality. In short, while there are some tempting possibilities, there doesn’t yet seem to be a useful solution.

In summary, it’s generally not attribution that people want (which can be licensed, even if you don’t like the layers of attribution that will require once you’re using multiple sources) but citation, which isn’t so easily licensed – yet. When deciding what sort of license to use (e.g. an open one like CC0 or an attribution-based one like CC-BY), you need to take into account expected usage. In some cases, for a leaf ontology, perhaps CC-BY is appropriate, as it isn’t intended to be imported by others, but you never know when your leaf will turn into something others import. Science Commons also believes that attribution is a very different beast, and shouldn’t be required when licensing data. They provided me with an answer to how to license ontologies recently that favored CC0.

So, if you really want citation and not attribution, consider an open license such as CC0 and make a gentlemanly (gentle-science-person-ly) request that if someone uses it AND publishes a paper on it, please cite it in the way you suggest. Alternatively, I’d be interested to hear if it would be possible to use an attribution-based license such as CC-BY and then require the attribution method be citation in a paper. Would this method work, and would it be polite? Your comments, please.

1.The ontology must be open and available to be used by all without any constraint other than (a) its origin must be acknowledged and (b) it is not to be altered and subsequently redistributed under the original name or with the same identifiers.

Licenses – This is always a touchy subject, within the life-sciences and IMHO largely due to a mis-understanding of what a license is actually for. Being open in the sciences is often mis-interpreted as “you can use it, but you have to attribute me”. This is actually not being open. The attribution aspect is actually a restriction. The principle of the OBO foundry  is that there will be hundreds of separate and orthogonal ontologies that will all refer and reference each other. If every single ontology has to be attributed this will become a large overhead. In addition, if we do insist on attribution, how do we acknowledge the use?  An official statement? Is importing the URI enough?  This aspect of the principles really needs to be explicit and clearly stated. Making use of  licenses that already exist may be a good starting point, rather than trying to define a bespoke OBO Foundry license. Two possibilities are Creative Commons – Attribution or CCO. The current OBO principles seem to merge these two licenses together. An explicit statement on licenses  is  really needed. Ally covers this in more detail on her post.

2. The ontology is in, or can be expressed in, a common shared syntax. This may be either the OBO syntax, extensions of this syntax, or OWL.

mm, this is confusing “expressed in a common shared syntax”, but you can use either OBO or OWL that would be two different syntax – no? Either the OBO foundry are in a shared syntax, or they are in OBO or OWL.

3. The ontologies possesses a unique identifier space within the OBO Foundry.

I would be good just to tighten this up a bit. A clear statement of the identification schema would be helpful

4. The ontology provider has procedures for identifying distinct successive versions.

This is a good statement and version of ontologies definitely need to be identified. As Ally mentions, we probably do not want to legislate which versioning system to use (svn, git etc). However maybe a recommendation of which to use and what constitutes a change may be helpful.

5. The ontology has a clearly specified and clearly delineated content.

How would you describe this to your users or developers? In ontology development this is traditionally called defining your scope. Your scope can be described by competency questions – questions your ontology should answer.

6.The ontologies include textual definitions for all terms.

A definition of a class in the ontology is its assertion in the hierarchy and all the logical restrictions, it can also include a natural language definition. I would re-word this to ” The classes in the ontology shoud have a natural language definition which reflection the logical definition of the class”.

7.The ontology uses relations which are unambiguously defined following the pattern of definitions laid down in the OBO Relation Ontology.

Same comment as Ally

8. The ontology is well documented.

Not really sure what this actually means or how to implement it. There are a set of naming recommendations within the OBO Foundry, is this what it is referring to? There are also metadata recommendation from OBI, is this the same thing?

9.The ontology has a plurality of independent users.

Why is this important as a principle for inclusion? Is listing on the OBO Foundry not an attempt to gain wider use? Are the computational users? is a user an individual, a  lab, a project, community?

10.The ontology will be developed collaboratively with other OBO Foundry members.

Why? Is this really a guiding development policy? What does collaboratively mean? In terms of the license? Does branching in a versioning repository count as collaborative development? I would suggest that if we get the terms of the license explicit an the idea of the Foundry then this principle is probably not necessary to be stated.

These comments are more a mix questions for debate rather than any clear cut corrections.

It is a lengthy document. Here is the abstract:

This paper addresses two research questions: “How should a well-engineered methodology facilitate the development of ontologies within communities of practice?” and “What methodology should be used?” If ontologies are to be developed by communities then the ontology development life cycle should be better understood within this context. This paper presents the Melting Point (MP), a proposed new methodology for developing ontologies within decentralized settings. It describes how MP was developed by taking best practices from other methodologies, provides details on recommended steps and recommended processes, and compares MP with alternatives. The methodology presented here is the product of direct first-hand experience and observation of biological communities of practice in which some of the authors have been involved. The Melting Point is a methodology engineered for decentralised communities of practice for which the designers of technology and the users may be the same group. As such, MP provides a potential foundation for the establishment of standard practices for ontology engineering.

I will be at the Molecular Regulation of Cardiac Disease Symposium May 14-15 2009, London, UK. Hosted by Abcam http://www.abcam.com/index.html?pageconfig=resource&rid=11503&sc_ql=1595&intGoUser=15