1. AHP And proposal
management
Gianmarco Piva
83864
10 May 2011
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2. The objective
• Selection of the best discount on the price for
a tender for a public work
• Maintenance and restoration of "Boboli
garden" in Florence, Italy
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3. The contract - content
• Supply of ornamental plants
• Creation and maintenance of green areas
• Pruning and felling of trees
• Creation of lawns
• Implementation of irrigation systems
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4. The contract -
characteristics
• All main features already defined ( price,
quality, timing, etc.)
• 2 constraints:
• Price fixed after contract is won
• Anomalous discounts rejected
• Historical data
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5. The hierarchical
structure
• Two constraints:
• Maximum of 9 alternatives (for simpler evaluation)
• Alternatives must represent real cases
• Experts questioned to draw hierarchical tree
( Delphi method )
• 31 criteria - 5 first level, 14 second level and 12
sub-level
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6. The alternatives
• Comparison between public work contracts
vs. ASSOVERDE prices
• Three different alternative ( three percentage
intervals )
• Interval chosen : 7 - 18 % of discount, divided
in 4 sub-alternatives
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7. Pairwise comparison
• Experts interviews and discussion to select
alternatives and weights of the criteria
• Individual interviews for criteria weighting
( see appendix 2 )
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8. Consistency issues
• Inconsistency ratio lower than 0.1
• Analysis is consistent and the judgements are
congruent and reliable
• Sensitivity analysis: only important changes to
the weight of first level criteria result in a
change of ranking of alternatives ( 0.12 to
0.40 in interest in the contract )
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9. Consistency -
objections
• Sensitivity analysis rolled out only for first level
criteria
• Interaction effects ignored ( considering two
or more relations )
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10. AHP considerations
• Relatively simple and effective
• Real-life applications
• User-friendly software
• Involvement of the experts
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11. Thank you!
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