Monotonicity: Difference between revisions

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(Add weak and strong possible monotonicity criterion to multi-winner section (speculative?))
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=== Woodall ===
=== Woodall ===
{{seealso|Douglas Woodall}}


Douglas Woodall defined several variations or types of monotonicity.<ref name="Woodall-Monotonicity"/> In Woodall's definitions, a candidate x should not be harmed if:
[[Douglas Woodall]] defined several variations or types of monotonicity.<ref name="Woodall-Monotonicity"/> In Woodall's definitions, a candidate x should not be harmed if:


* l ([[Mono-raise criterion|'''MONO-RAISE''']]) x is raised on some ballots without changing the orders of the other candidates;
* l ([[Mono-raise criterion|'''MONO-RAISE''']]) x is raised on some ballots without changing the orders of the other candidates;
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* l (MONO-ADD-PLUMP): A candidate {{math|''x''}} should not be harmed if further ballots are added that have {{math|''x''}} top with no second choice.
* l (MONO-ADD-PLUMP): A candidate {{math|''x''}} should not be harmed if further ballots are added that have {{math|''x''}} top with no second choice.
* l ([[Mono-add-top criterion|'''MONO-ADD-TOP''']]) further ballots are added that have x top (and are otherwise arbitrary);
* l ([[Mono-add-top criterion|'''MONO-ADD-TOP''']]) further ballots are added that have x top (and are otherwise arbitrary);
* l (MONO-REMOVE-BOTTOM) some ballots are removed, all of which have x bottom, below all other candidates.
* l (MONO-REMOVE-BOTTOM) some ballots are removed, all of which have x bottom, below all other candidates.



=== Multi-winner monotonicity ===
=== Multi-winner monotonicity ===