|
In most decision problems it will be useful to develop an
objectives hierarchy to group similar objectives. Once a list of
issues or preliminary "objectives" has been
brainstormed, you can build a fundamental objectives hierarchy
by continually asking "what do you mean by that?"
Consider for example, a park planning exercise in which the
fundamental objectives are defined as: "Protect
Wildlife", "Maximize Recreational Opportunities"
and "Minimize Net Cost". Asking "what do you mean
by that?" may lead you to several sub-objectives that
further describe exactly what is meant by these terms in this
particular decision context. For example:
Protect Wildlife |
|
Minimize Disturbance |
|
Enhance Habitat Quality |
|
Maximize Recreational Opportunities |
|
Maximize Quantity of Use |
|
|
Maximize Land-based Use |
|
|
Maximize Water-based Use |
|
Maximize Quality of Experience |
|
|
Maximize Visual quality |
|
|
Minimize Noise |
|
|
Maximize Probability of Wildlife Sightings |
|
|
Minimize Crowding |
|
Minimize Net Cost |
|
Maximize Revenue |
|
Minimize Management Cost |
Any objective may have different interpretations depending on
the decision context. Through this hierarchy you have defined
exactly what you mean by each fundamental objective for this
context. Recreational Quality for example, would likely be
defined quite differently for say an amusement park, or a fly
fishing resort. With the objectives hierarchy, you have defined
all the important elements of recreational opportunity that can
be affected by this decision. Each of the lowest level
objectives will now need an evaluation criterion to be defined.
Using Mean-Ends Diagrams to Help with Objectives
Hierarchies
A means-ends diagram is a kind of conceptual model that
visually shows the relationship between policy alternatives
(means) at one end and fundamental objectives (ends) at the
other. It is useful for developing a conceptual understanding of
a system, for helping separate interests (objectives) from
positions (means), and for identifying potential evaluation
criteria. During brainstorming and objectives structuring
discussions, it is often useful to quickly trace out means-ends
relationships to help people see how the issues they are
concerned about fit into the decision process. Besides being
important from a decision quality perspective, this helps people
to see that issues that are not "fundamental
objectives" still have a place in the process and will be
addressed.
Below is a mean-ends diagram developed for the park
management decision described above. Management objectives
include maximizing the quality of visitor experiences,
protecting wildlife and minimizing net management cost.
Fundamental objectives are shown at the far right, with proposed
means shown at the left. The diagram shows that crowding is an
important contributor to the quality of experience. It shows how
instituting pay parking can address crowding and consequently
crowding. It also shows that it affects other objectives at the
same time.
Similar diagrams (or additional detail added to this one)
might be constructed to show that there are other means of
achieving these objectives. For example, the provision of more
facilities or zoning the park to accommodate conflicting uses
might be other ways to enhance the quality of the experience and
protect wildlife that don't involve reducing park usage.
Reducing users (and pay parking in particular) is only one means
of achieving the fundamental objectives.
Next>> |
