{"paper":{"title":"Ballot Exhaustion in Multiwinner Single Transferable Vote Elections","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"Raw ballot exhaustion rates in multiwinner STV overstate how often voters lose representation.","cross_cats":["q-fin.EC"],"primary_cat":"econ.GN","authors_text":"David McCune, E.E. Naber","submitted_at":"2026-05-12T19:26:40Z","abstract_excerpt":"We study ballot exhaustion in multiwinner single transferable vote (STV) elections using a dataset of 1,070 Scottish local government elections comprising over 5.4 million ballots. While ballot exhaustion has been studied extensively in single-winner elections, comparatively little work examines exhaustion in the multiwinner setting. We introduce formal definitions of several types of exhaustion in STV elections, distinguishing between exhausted ballots, non-first-choice exhausted ballots, unrepresented exhausted ballots, and weight exhaustion. These definitions clarify important conceptual di"},"claims":{"count":4,"items":[{"kind":"strongest_claim","text":"raw exhaustion rates alone substantially overstate the extent to which voters lose their influence or fail to obtain representation under STV.","source":"verdict.strongest_claim","status":"machine_extracted","claim_id":"C1","attestation":"unclaimed"},{"kind":"weakest_assumption","text":"The proportional ballot-completion model accurately reflects how voters would complete their ballots if given more options.","source":"verdict.weakest_assumption","status":"machine_extracted","claim_id":"C2","attestation":"unclaimed"},{"kind":"one_line_summary","text":"27.9% of ballots exhaust in Scottish STV elections but weight exhaustion is only 7.1%, and most voters still achieve representation.","source":"verdict.one_line_summary","status":"machine_extracted","claim_id":"C3","attestation":"unclaimed"},{"kind":"headline","text":"Raw ballot exhaustion rates in multiwinner STV overstate how often voters lose representation.","source":"verdict.pith_extraction.headline","status":"machine_extracted","claim_id":"C4","attestation":"unclaimed"}],"snapshot_sha256":"1a7717fd049dd55bcacbdbe26226f116e91536026381c39beef58b3547e3a4b8"},"source":{"id":"2605.12676","kind":"arxiv","version":1},"verdict":{"id":"f302ab0d-42e4-4c06-99b2-fdb8aaab29a8","model_set":{"reader":"grok-4.3"},"created_at":"2026-05-14T20:11:07.313208Z","strongest_claim":"raw exhaustion rates alone substantially overstate the extent to which voters lose their influence or fail to obtain representation under STV.","one_line_summary":"27.9% of ballots exhaust in Scottish STV elections but weight exhaustion is only 7.1%, and most voters still achieve representation.","pipeline_version":"pith-pipeline@v0.9.0","weakest_assumption":"The proportional ballot-completion model accurately reflects how voters would complete their ballots if given more options.","pith_extraction_headline":"Raw ballot exhaustion rates in multiwinner STV overstate how often voters lose representation."},"references":{"count":23,"sample":[{"doi":"","year":2024,"title":"T. Bardal, M. Brill, D. McCune, & J. Peters. (2024). Proportional Representation in Practice: Quantifying Proportionality in Ordinal Elections.Proceedings of the AAAI Conference on Artificial Intellig","work_id":"d19a3c3d-4e5d-47ae-907f-275966fcd3fa","ref_index":1,"cited_arxiv_id":"","is_internal_anchor":false},{"doi":"","year":2024,"title":"G. Benad` e, C. Donnay, M. Duchin, and T. Weighill. (2024) Proportionality for ranked voting, in theory and practice. Preprint:https://mggg.org/PRVTP","work_id":"8609bd6a-9982-49f8-9798-61357dbd31da","ref_index":2,"cited_arxiv_id":"","is_internal_anchor":false},{"doi":"","year":2015,"title":"C.M. Burnett & V. Kogan. (2015). Ballot (and voter) “exhaustion” under Instant Runoff Voting: An examination of four ranked-choice elections.Electoral Studies37: 41-49","work_id":"7f225c24-d232-4aa1-bb01-ba512fec1602","ref_index":3,"cited_arxiv_id":"","is_internal_anchor":false},{"doi":"","year":2013,"title":"A. Clark. (2013). Second time lucky? The continuing adaptation of voters and parties to the single transferable vote in Scotland.Representation49(1): 55-68","work_id":"ae068cc3-902a-4528-bb24-8a995c970d8f","ref_index":4,"cited_arxiv_id":"","is_internal_anchor":false},{"doi":"","year":2021,"title":"A. Clark. (2021). The effects of electoral reform on party campaigns, voters and party systems at the local level: from single member plurality to the single transferable vote in Scotland.Local Govern","work_id":"a26978d0-cfb2-4f7d-9b92-61ee75532aec","ref_index":5,"cited_arxiv_id":"","is_internal_anchor":false}],"resolved_work":23,"snapshot_sha256":"96f8240b0b3deb1db11fa76e95c0a25acc7cd4ae13cee5d67c1560aec9138a88","internal_anchors":0},"formal_canon":{"evidence_count":1,"snapshot_sha256":"657f7eb83bc40c70eca8f659ca141d6b6f8239c541558d4d0dcadbe9b7955288"},"author_claims":{"count":0,"strong_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"builder_version":"pith-number-builder-2026-05-17-v1"}