Modelling is building Models for the representation of modules, i. e. the entities of a System.
Modelling requires one to:
- Decompose the system into its basic entities
- Identify the essential/relevant entities and linkages
- Recompose a simplified/selected version of the system with its essential/relevant entities and linkages (i.e. the model)
A Model is a selected simplified representation of the essential or relevant entities (modules) of some specific reality and their characteristics (fields, factors, features).
The basic types of Models are:
An Iconic Model is a look-alike representation of some specific entity (e.g. a house)
Iconic Models can be represented in:
- Two Dimensions : e.g. photos, drawings, etc.
- Three Dimensions : e.g. scale model
A scale model can be a:
- reduction (scaled down, e.g. the model of a building)
- reproduction (same scale, e.g. copy model, prototype or working model)
- enlargement (scaled up, e.g. the model of an atom)
of some specific entity
An Analogue Model is the representation of entities of a system by analogue entities pertaining to the model (e.g. through diagrams).
An Analogue Model can be built through:
- Two Dimensional Visualization : Charts, Graphs, Diagrams
(e.g. the colour coding of a geographical chart for representing different altitudes)
- Three Dimensional Visualization : Analogue Devices
(e.g. the flow of water in pipes to represent the flow of electricity in wires or the flow of resources in an economic system)
A Symbolic Model is the representation of entities of a system through symbols.
Symbols can be:
A Symbolic Model is used whenever the reality is:
- too complex or too abstract to be portrayed through an iconic or analogue model
- the factors of the system (variables) can be represented by symbols that can be manipulated in a meaningful and fruitful way
Modelling : summing up (^)
Modelling is the building of Models.
Models can be:
The use of Models allows for:
Extrapolation is achieved through manipulation of Models with a view to Simulating.