Importance of
Modeling
What is Modeling?
·
A model is a simplification of reality
·
Modeling can be done for both simple and complex
systems. It is more important for complex systems to understand them completely
·
A model may provide blueprints of a system that
show both the structure and behavior
o
Structure means parts of the system and their
relationships
For
Example: A table has a top and legs. And, they are connected to form a
table
o
Behavior defines the system's actions and how
different parts contribute to it
Example: Learning
is a part of college. Teachers teach and students learn. And the management
organizes resources to make sure learning is carried out
Types of Models
• Different types of
models are used in practice
For
example
- o A Curriculum Vitae (CV) is written in a textual model
- o Representation of problems in the form of equations is a mathematical model
- o Directions from one place to another are best shown as a map
- o Parts of human body are best represented as a pictorial model
- o A tabular model is a good way to capture details about a list of things
- o Organization hierarchies are often represented as organization charts
- o An algorithm is best understood in terms of a flow chart
Aims of modeling
A model:
·
Helps to visualize a system as it is or the way
wanted
Example: Flowcharts help us to visualize an algorithm
·
Specifies the structure or behavior of a system
Example:
Class diagrams in software systems show the system structure where as
interaction diagrams show the behavior
A picture can be used to depict the structure of a human
body
·
Gives a template that guides in constructing a
system
Example: SRS for a software system
·
Document the decisions made
Example: An architecture document specifies the
architectural decisions
Principles of Modeling
Principles of Modeling are:
Ø
Choice of Model is Important
Ø
Levels of Precision may differ
Ø
Connected to Reality
Ø
No Single Model is Sufficient
Choice of Model is Important:
Depending
on the nature of the problem and the solution, we choose an appropriate type of
model
Levels of Precision May Differ:
Every
model may be expressed at different levels of precision
The
best kinds of models help to choose degree of detail. It depends on the person
viewing the model and the need to view it
Best Models are connected to Reality:
All
models simplify reality
Hence,
we have to ensure that simplification does not hide any important details e.g.
a simulation of a flight should consider different weather conditions
No Single Model is Sufficient:
Every
complex system is approached by a set of independent models
We
create models that can be built and studied separately, making sure that these
models are still interrelated
