AggregationOperator
WAM: Weighted Arithmetic Mean
Yager, R. R. · 1988
Overview
Linear additive aggregation operator. Output typically rank_position (lower value = preferred).
Strengths
- •Method-specific: Linear additive aggregation operator
Limitations
- •Assumes: Input is a rank matrix (1=best, m=worst per voter)
- •Assumes: Each voter ranks all alternatives
Method assistant
Grounded explanations: it explains the method, it does not compute.
Assumptions to verify
- •Input is a rank matrix (1=best, m=worst per voter)
- •Each voter ranks all alternatives
When not to use
- •Cardinal preferences important → use a MAUT method
Edge cases
- •See F.steps and D.parameters for WAM-specific edge handling. recommendation_metadata.assumptions_to_verify also lists boundary conditions.
Common pitfalls
- •Hatalı: 'WAM bu varsayımı kontrol etmeden uygulamak'. Doğrusu: Input is a rank matrix (1=best, m=worst per voter)
- •Hatalı: 'WAM bu varsayımı kontrol etmeden uygulamak'. Doğrusu: Each voter ranks all alternatives
- •Hatalı: WAM'yi 'Cardinal preferences important → use a MAUT method' durumunda kullanmak: recommendation_metadata.not_recommended_when alternatif öneriyor.
Worked example
- 1.Adım 1 (F1): Step 1: Validate weights satisfy Σw_j = 1 and w_j ≥ 0. Formül: \sum_{j=1}^{n} w_{j} = 1,\quad w_{j}\ge 0 Anchor: Yager 1988, p.184 Eq.(1)
- 2.Adım 2 (F2): Step 2: Weighted arithmetic mean WAM(x_1,…,x_n) = Σ w_j x_j. Formül: \text{WAM}(x_{1},\ldots,x_{n}) = \sum_{j=1}^{n} w_{j}\,x_{j} Anchor: Yager 1988, p.184 Eq.(2)
- 3.Adım 3 (F3): Step 3: Apply WAM per alternative; descending ranking. Formül: S_{i} = \sum_{j=1}^{n} w_{j}\,x_{ij},\quad i=1,\ldots,m Anchor: Yager 1988, p.185 Eq.(3)
How to cite
Yager, R. R. (1988). On ordered weighted averaging aggregation operators in multicriteria decisionmaking. IEEE Transactions on Systems, Man, and Cybernetics. https://doi.org/10.1109/21.87068