Evaluation Criteria
Weighted scoring in a procurement evaluation is a method to assess and compare vendor proposals systematically and objectively.
When evaluations involve two levels of criteria — main criteria and their respective sub-criteria — the calculations ensure that both levels are appropriately weighted based on their relative importance. This ensures decisions align with your organisation’s priorities.
Here’s how the calculations are created and structured in Cotiss:
1. Define and Structure Evaluation Criteria
Main Criteria: These are the high-level areas of evaluation, typically based on organisational priorities such as Cost, Quality, Delivery, or Technical Capability.
Sub-Criteria: These are the detailed factors under each main criterion. For instance:
Cost → Upfront Cost, Ongoing Costs.
Quality → Durability, Reliability.
Example:
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Example:
Cost = 40%
Quality = 35%
Delivery Time = 25%
2. Assign Weights to the Main Criteria
Determine the relative importance of each main criterion based on organizational priorities.
Assign weights to each main criterion.
Example:
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3. Distribute Weights Among Sub-Criteria
Each main criterion’s weight is further distributed among its sub-criteria based on their relative importance within that criterion.
Example:
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The total sub-criteria weights under a main criterion must equal that criterion’s weight.
4. Score Vendors on Sub-Criteria
Vendors are evaluated for each sub-criterion using a defined scale, such as:
1 to 5, where 1 = Poor and 5 = Excellent.
1 to 10, for finer granularity.
Example:
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5. Calculate Weighted Scores for Each Sub-Criterion
Multiply the vendor’s score for each sub-criterion by its total weight (main criterion weight × sub-criterion weight).
Formula:
Example: For Cost (40%) with two sub-criteria:
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6. Aggregate Scores for Main Criteria
Sum the weighted scores of all sub-criteria under each main criterion to get the vendor’s total score for that criterion.
Formula:
Example:
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7. Calculate the Vendor’s Final Weighted Score
Sum the scores of all main criteria to determine the vendor’s overall performance.
Formula:
Example:
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Criteria | Weight | Sub-Criteria | Weight | Vendor Score | Weighted Score |
Cost (40%) | 40% | Upfront Cost | 30% | 8 | 0.4 × 0.3 × 8 = 0.96 |
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| Ongoing Costs | 10% | 7 | 0.4 × 0.1 × 7 = 0.28 |
Quality (35%) | 35% | Reliability | 20% | 9 | 0.35 × 0.2 × 9 = 0.63 |
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| Durability | 15% | 9 | 0.35 × 0.15 × 6 = 0.32 |
Delivery (25%) | 25% | Lead Time | 15% | 8 | 0.25 × 0.15 × 8 = 0.3 |
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| Flexibility | 10% | 7 | 0.25 × 0.1 × 7 = 0.18 |
Total Weighted Score for Vendor: 0.96 + 0.28 + 0.63 + 0.32 + 0.3 + 0.18 = 2.67