Basic Modelling Concepts

Modelling as the act of conceptualising a real thing in either:

(a) Mathematical framework

(b) Visual framework

which gives the symbolic and semantic meanings of the real thing.

To begin with, think of:

Conceptual Integrity in EA Modelling

Conceptual integrity is the degree to which a model can be understood by a single human mind, despite its complexity.

……. occurs when a design presents a single, coherent and easily understood vision

Basic Modelling Activities

Establish purpose, scope & focus of

modelling

Select one or more Viewpoints to model

Create & Structure the Models

Visualise the Models

Maintain the Models

Validate & then use the Models

Modelling is:

Conceptualising domains (parts) of reality knowledge

CREATE conceptsREFINE conceptsABANDON conceptsABSTRACT from conceptsTRANSLATE concepts

Modelling Actionswhich are also documented

Modelling (Internal) Quality Assurance

Heuristics = method of solving a problem by experience

Modelling is heuristic and the integrity of modelling reality as conceptual symbols & semantics is subject to Lankhort’s design principles, which are considered internal quality characteristics:

1. Do not link what is independent (orthogonality)

2. Do not introduce multiple functions that are slightly divergent (generality)

3. Do not introduce what is irrelevant (economy; sometimes denoted as parsimony)

Modelling (External) Quality AssuranceModelling is also subject to external quality assurance:

1. Fit for purpose validation by EA stakeholders, to confirm the correctness and completeness of the EA models;

2. Complying to Grice’s 4 Maxims of optimising the communications of EA models via its visual forms:

Maxim of Quantity:• Make your model as informative

as necessary.• Do not make your model more

informative than necessary.

Maxim of Quality• Do not model what you believe

to be false.• Do not model that for which you

lack adequate evidence.

Maxim of Manner• Avoid obscurity of expression.• Avoid ambiguity.• Be brief (avoid unnecessary

concepts and relations).• Be orderly.

Maxim of Relevance• Be relevant (i.e., model things

related to the modelling goal).

Modelling (External) Quality AssuranceModelling is also subject to external quality assurance:

1. Fit for purpose validation by EA stakeholders, to confirm the correctness and completeness of the EA models;

2. Complying to Grice’s 4 Maxims of optimising the communications of EA models via its visual forms;

3. Lankhorst’s guidelines:• Model iteratively• Model for change / dynamics• Be economical in models• Be economic in views• Make concepts recognisable• Make structures recognisable• Make a model consistent• Keep related models consistent• Make models as correct & completed as needed• Treat different concerns separately

Modelling Guidelines

Act of MODELLING

Pre-start Check-list:

1. Is there a clear stakeholder?2. Is the objective explicit?3. Will creating an enterprise

architecture model help to reach this objective?

4. Are the boundaries clear of what you should model?

5. Is it clear whether the situation ‘as is’ or the situation ‘to be’ should be modelled?

6. Can you obtain the information needed to create the model?

7. Are there realistic expectations regarding your role as an enterprise architect in the process?

8. What to capture in a model

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Modelling Guidelines

Readability (easy to read) & Usability (easy to use) of Models

1. Reduce visual complexity of models

2. Use representation conventions eg naming & indentation conventions; layout rules, use of symbols, colours, text, etc

Basic Modelling Activities

ModelA purpose driven

abstract conception of reality

VisualisationA form of visual communications

Differences Between Model & Visualisation(read Lankhorst chapter 3 & 6 for full details)

Has to provide answers to Qs,

Has an underlying

problem solving heuristic /method

Communications Purpose

Tut Case Study

Decision making is considered a service, which is associated with the provision of good governance to a Council's community. The Vic Local Government Ministry considers that good Council decision making, as a community service, shows evidence of community engagement, compliance to policy frameworks, agreed practice standards and the relevant legislation.

It is consider a measureable objective that every Victorian Council is expected to show they make and implement decisions that in the best interests of their community. The achievement of this objective is measured by a number of indicators, summarized in the diagram overleaf

Case Study

Use any viewpoint to model this Local Government Governance KPI domain.Try a ER model first