On the price of diversity for multiwinner elections under (weakly) separable scoring rules

Mostapha Diss (), Clinton Gubong Gassi and Eric Kamwa ()
Additional contact information
Mostapha Diss: CRESE - Centre de REcherches sur les Stratégies Economiques (UR 3190) - UFC - Université de Franche-Comté - UBFC - Université Bourgogne Franche-Comté [COMUE], AIRESS - Africa Institute for Research in Economics and Social Sciences
Clinton Gubong Gassi: CRESE - Centre de REcherches sur les Stratégies Economiques (UR 3190) - UFC - Université de Franche-Comté - UBFC - Université Bourgogne Franche-Comté [COMUE], department of mathematics University of yaounde 1
Eric Kamwa: BETA - Bureau d'Économie Théorique et Appliquée - AgroParisTech - UNISTRA - Université de Strasbourg - Université de Haute-Alsace (UHA) - Université de Haute-Alsace (UHA) Mulhouse - Colmar - UL - Université de Lorraine - CNRS - Centre National de la Recherche Scientifique - INRAE - Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement

Post-Print from HAL

Abstract: We consider a model of multi-winner elections, where each voter expresses a linear preference over a finite set of alternatives. Based on voters' preferences, the primary goal is to select a subset of admissible alternatives, forming what is referred to as a committee. We explore (weakly) separable committee scoring rules, the voting mechanisms that assess each alternative individually using a scoring vector and select the top k alternatives, where k represents the committee's size. Furthermore, we operate under the assumption that alternatives are categorized based on specific attributes. Within each attribute category, there exists a targeted minimum number of alternatives that the selected committee should encompass, emphasizing the necessity for diversity. In this context, we assess the cost associated with imposing such a diversity constraint on the voting process. This assessment is conducted through two methodologies, referred to as the "price of diversity" and the "individual price of diversity". We set the upper bounds for both prices across all (weakly) separable committee scoring rules. Additionally, we show how the maximum price of diver- sity can be used to discriminate between different voting rules in this context. Ultimately, we illustrate that concentrating on the candidates' performance yields a more accurate estimation of the price of diversity compared to a focus on the enforced diversity constraint.

Keywords: Group decisions and negotiations; Voting; Multiwinner elections; Scoring rules; Price of diversity (search for similar items in EconPapers)
Date: 2025
Note: View the original document on HAL open archive server: https://univ-fcomte.hal.science/hal-04390700v1
References: Add references at CitEc
Citations:

Published in European Journal of Operational Research, In press, 25 p. ⟨10.1016/j.ejor.2025.06.013⟩

Downloads: (external link)
https://univ-fcomte.hal.science/hal-04390700v1/document (application/pdf)

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:hal:journl:hal-04390700

DOI: 10.1016/j.ejor.2025.06.013

Access Statistics for this paper

More papers in Post-Print from HAL
Bibliographic data for series maintained by CCSD ().