Building an Evidence Ontology


I have already highlighted in several earlier posts the aspects and importance of evidence but i am going to revisit particular key messages to explain the benefits from formalising the structure of evidence in order for it to support and improve EA knowledge.

  • The evidence ontology needs to be able to bring together a variety of research to strengthen hypotheses and recommendations in the artefacts and methods used in the architecture development method.
  • The evidence ontology needs to be able to support the internal EA content behind new views and scenarios as well as incorporate evidence from external sources.
  • Finally the evidence ontology needs to be able to support the formation of an evidence knowledge base that is flexible to help the engineering of future organisation models.
  • The evidence ontology needs to be able to enable the cross referencing required to demonstrate the importance of pattern and knowledge rules

You may be asking what is the point of building up a model of evidence to such a degree as an ontology. The main reason is that it is a relatively simple model and by doing so you are able to decide upon what constitutes evidence, how you characterise it and how you build and approve it. Otherwise any supporting evidence looses it importance if it does not have foundation. The reason i choose to use Cyber Defence evidence as an example it that the lessons and knowledge gained from understanding threats, risk and vulnerabilities in your organisation is vital to your architectural development now and in the future. That is not to say that evidence in Marketing, Sales or Product / Service development is less important, it is not, as any evidence used to support decision making is vital to develop and sustain a business.

So back to the Evidence Ontology and a proposed high level structure. at the top level the Evidence Ontology looks as follows:

  • Evidence research
  • Evidence development
  • Evidence synthesis
  • Evidence evaluation
  • Hypothesis
  • Evidence monograph
  • Evidence attributes

Each of these classes is further defined by sub classes as demonstrated in the attached image file. I have collected these classes from various sources of information and they represent my view of the necessary requirements to cover the process, classification, evaluation and provision of evidence material to support any decision based activity such as planning, strategy and enterprise architecture. I will continue in the next post with a look at the properties and relationships to the decision based activities through examples.

Evidence Ontology
Evidence Ontology

All architects should be trained on how to perform evidence research and evidence analysis – principle 7


It was only after working for a research institute that i began to fully appreciate the capabilities and time required when conducting research for evidence. This institute employed research librarians, research analysts and specialist researchers to support the teams building clinical evidence. These individuals collectively located evidence, analysed it and stored and maintained it for use in several large knowledge databases.

In order to apply evidence based enterprise architecture, Architects should at least be trained on the basic techniques of research, analysing the information they find and how to apply it. This should include setting the objectives of the research, defining the questions to answer, undertaking literature reviews and collecting the information for analysis. Finally, identifying the appropriate evidence required to support their hypothesis and conveying that through their documentation.

I don’t however expect Architects to become experts in this area. The architecture practice within an organisation should make a judgement on how it develops this capability and whether or not it requires specialist resources.

Using an evidence model to define how an organisation classifies evidence and evidence value – principle 6


During my research into the subject of evidence based practices and how to apply the approach to enterprise architecture i have only come across three models or metamodels associated with evidence. The first comes from a publication called Enterprise Architecture – Models and Analysis for Information Systems Decision Making by Pontus Johnson and Mathias Ekstedt (a very good book and i recommend reading it) the second and third are models from the OMG website on the subjects of Software Assurance Evidence Metamodel (SAEM) and Argument Metamodel (ARM). Non of these models fulfil all of the requirements i was looking for as a model to support evidence based enterprise architecture however they provide useful associations. The two models from OMG are software related and thus would be useful in the area of software development. The model from the publication is a high level model giving the main subject areas.

For this principle I recommend that an organisation produces an evidence model to define how they classify evidence, value it, analyse it and apply it. In future posts i will offer descriptions of the model i have been developing.