Decision Support Tool (DST)
What is the
Decision Support
Tool?
© 2006 IARC
Hybrid Vehicle Projects
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Decision Support Tool (DST)
What is the DST?
A way of helping make decisions related to
hybrid vehicles
Decisions can be complex, multi-faceted and often have to be
made with limited information…
..using the DST will make decision-making easier, faster and
repeatable.
© 2006 IARC
Hybrid Vehicle Projects
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Decision Support Tool (DST)
Who is it
applicable to?
© 2006 IARC
Hybrid Vehicle Projects
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Decision Support Tool (DST)
Who is it applicable to?
Members of
the public
Commercial
Users
Suppliers
Local/National
Government
Vehicle Manufacturers
© 2006 IARC
Hybrid Vehicle Projects
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Decision Support Tool (DST)
How does it
work?
© 2006 IARC
Hybrid Vehicle Projects
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Decision Support Tool (DST)
How does it work?
STEP 1 – DECISION QUESTION
Start by defining the decision to be
supported.
Decisions categorised by decision maker
type and decision type to aid selection.
EXAMPLE
I’m a private consumer
PUBLIC
I’m making a decision relating to vehicle PURCHASE
Decision – I need to decide …
… which vehicle to purchase from a set of identified
vehicles?
© 2006 IARC
Hybrid Vehicle Projects
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Decision Support Tool (DST)
How does it work?
STEP 2 – VALUE PROFILE
Identify what is important to the decision
maker – their value set.
Nesting allows for level of detail to reflect
knowledge of user.
EXAMPLE – Vehicle Purchase
Specify importance on 0 (lowest) to 10 (highest)
importance for set of factors relevant to purchase
decisions.
Both quantifiable aspects such as purchase cost and
subjective factors such as aesthetics (appearance) can
be included.
© 2006 IARC
Hybrid Vehicle Projects
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Decision Support Tool (DST)
How does it work?
STEP 3 – VALUE PROFILE(2)
Identify how the decision maker’s
preference varies with variations in the
factors on which the decision is based.
EXAMPLE – Purchase Cost
When does a difference in price between 2 vehicles
impact your preference for a vehicle?
e.g. if you are considering between 2 £20k vehicles,
does £100 difference in price influence your decision, or
are you indifferent to such a small price difference?
© 2006 IARC
Hybrid Vehicle Projects
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Decision Support Tool (DST)
How does it work?
STEP 4 – DECISION SPECIFICATION
Define the scenario in which the decision is
being made i.e. information which provides
context for the decision.
EXAMPLE – Vehicle Purchase
Information captured about how and where the
vehicle is used.
• road types – motorway, urban etc.
• driving style
• across congestion charging zone?
• annual mileage
© 2006 IARC
Hybrid Vehicle Projects
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Decision Support Tool (DST)
How does it work?
STEP 4 – DECISION SPECN (2)
Specify each of the options being
considered and evaluated, both factual and
subjective impressions.
EXAMPLE – Vehicle Purchase
Information captured about the vehicles.
• Factual – weight, drag co-efficient etc.
• Subjective – aesthetics, image etc.
Data, such as fuel economy might be entered directly, or
generated through simulation.
© 2006 IARC
Hybrid Vehicle Projects
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Decision Support Tool (DST)
How does it work?
STEP 5 – DATA PROCESSING
Input data is now processed using
PROMETHEE methodology.
Might include simulations, cost model
calculations etc. to generate data.
EXAMPLE – Vehicle Purchase
Vehicle simulation - WARPSTAR returns fuel
economy for a drive cycle generated based on
users use profile.
g/km
Figure more representative of real-world economy.
© 2006 IARC
Hybrid Vehicle Projects
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Decision Support Tool (DST)
How does it work?
STEP 6 – RESULTS
Options ranked. This might include
continuous options such as determining
optimum price.
Confidence in results also indicated.
EXAMPLE – Vehicle Purchase
Vehicle
Satisfaction
Index
Toyota Prius
5.45
Honda IMA
3.2
Jaguar X
Type
4.5
Vehicles ranked according to preference of
decision maker
Based on specified value set and specification
data.
© 2006 IARC
Hybrid Vehicle Projects
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Decision Support Tool (DST)
How does it work?
STEP 7 – DESIGN BY ITERATION
What if questions analysed. Tool could be
used recursively but slow.
Automation through inputs as variables or
targets.
EXAMPLE – Vehicle Purchase
?
What if someone else also drives the vehicle?
What if I do less/more miles per annum?
What if ….
© 2006 IARC
Hybrid Vehicle Projects
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Decision Support Tool (DST)
What are the
benefits of
using the DST?
© 2006 IARC
Hybrid Vehicle Projects
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Decision Support Tool (DST)
What are the benefits of using the DST?
Improved decision making through
• consideration of factors in a structured format.
• ability to test sensitivity to changes.
• assistance in generation of accurate data e.g. link
to simulation.
• capture of different perspectives across business
in a formal, non-technical manner.
© 2006 IARC
Hybrid Vehicle Projects
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Decision Support Tool (DST)
What are the benefits of using the DST?
Leads to :
• Accelerated decision taking through clear process and
identification of required information.
• Reduced changes in programme.
• Easy-to-review reasoning behind decisions taken as auto
captured and documented.
• Easy to see the effects of changes during programme if
assumptions used differ from reality.
Business Benefits :
• Reduced time to market
• Reduced rework
© 2006 IARC
Hybrid Vehicle Projects
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