Transcript C

CHAPTER SEVEN
Model complexity
Business models must be kept simple so that they can be
easily understood by others.
It is much easier to build a complex model than to build a
simple one.
Creating simple models takes skill. Novice modelers create
overly complex, incomprehensible models because the
world they are modeling is always complex.
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CHAPTER SEVEN
Model complexity
But how do you create simple business models?
There are three simplifying techniques:
1. Model element omission
2. Selective revelation
3. Hierarchy and decomposition
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CHAPTER SEVEN
Model complexity
Model element omission
just omit unnecessary model elements.
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CHAPTER SEVEN
Model complexity
Selective revelation
The model is selectively revealed, one diagram at a time.
The model is shown in several diagrams, each one of which
is simple enough to understand on its own.
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Model complexity
Hierarchy and decomposition
Some model elements are aggregated together into a
composite model element. The details are underneath.
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CHAPTER SEVEN
Bad names
Model elements can be named poorly and often are.
What are the characteristics of a good name for a model
element?
A good name is short: two, three, or four words are best.
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Bad names
A good name is short: two, three, or four words are best.
If you are tempted to write a long model element name to
explain details, you should instead describe those details
in the model element description.
The name should describe the intent of a model element,
not the implementation.
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CHAPTER SEVEN
Bad names
The name should describe the intent of a model element,
not the implementation.
The implementation might change over time, even as the
intent stays the same. “Validate Customer” is better than
“Run search for customer name in CRM system” You may
later validate the customer using another system.
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Bad names
CAC
Avoid acronyms
Receive/Send New/Updated Enrollment/Registration data
from system
Avoid slashes
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Bad names
Model element names should generally be unique
in a large model, you might be able to create unique
names only by resorting to numeric suffixes, e.g., “Validate
Customer 23”
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CHAPTER SEVEN
Weak descriptions
every named model element should have a written
description.
The description of a model element should be a
paragraph or two that is easy to read and easy to
understand by someone who is not a modeler.
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Weak descriptions
A model element description should be about the model
element, not how the model element is associated with
other elements.
The description should be understandable, well written,
and long enough to explain the association.
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Weak descriptions
A modeler should be able to change the process by
rearranging the sequence flow changing the
descriptions of individual activities.
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CHAPTER SEVEN
Ugly models
What actions can you take to make a model attractive?
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Ugly models
What actions can you take to make a model attractive?
Change the size of model elements. For example, a
business process model looks better when all the activities
are the same size.
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Ugly models
What actions can you take to make a model attractive?
Rearrange model elements. A model looks better when
related model elements are close to each other, making
the associations or flows between them short and straight.
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Ugly models
What actions can you take to make a model attractive?
Draw the associations without kinks or crossing lines. For
example, an interaction model with simple straight lines
that do not cross looks better than one with intersecting
interactions.
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Ugly models
What actions can you take to make a model attractive?
Draw sequence flows in business process models from left
to right.
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Ugly models
What actions can you take to make a model attractive?
Align and distribute model elements.
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Ugly models
What actions can you take to make a model attractive?
Change the font size. A model looks better when it has
uniform font size that is large enough to read.
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Ugly models
What actions can you take to make a model attractive?
Arrange the names of model elements. The names of the
model elements are displayed as text on the diagram. Text
looks better when it does not overlap with model elements,
associations, or other text.
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Ugly models
What actions can you take to make a model attractive?
Use a complementary color palette. Color is often used in
a motivation model, with goals, strategies, influencers, and
assessments distinguished by different colors. Colored
models look better when the colors complement each
other rather than clash.
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