{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,18]],"date-time":"2026-03-18T02:58:51Z","timestamp":1773802731625,"version":"3.50.1"},"reference-count":0,"publisher":"Association for the Advancement of Artificial Intelligence (AAAI)","issue":"20","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["AAAI"],"abstract":"<jats:p>Despite extensive theoretical research on proportionality in\napproval-based multiwinner voting, its impact on which committees and candidates can be selected in practice remains\npoorly understood. We address this gap by (i) analyzing the\ncomputational complexity of several natural problems related\nto the behavior of proportionality axioms, and (ii) conducting an extensive experimental study on both real-world and\nsynthetic elections. Our findings reveal substantial variation\nin the restrictiveness of proportionality across instances, including previously unobserved high levels of restrictiveness\nin some real-world cases. We also introduce and evaluate new\nmeasures for quantifying a candidate\u2019s importance for achieving proportional outcomes, which differ clearly from assessing candidate strength by approval score.<\/jats:p>","DOI":"10.1609\/aaai.v40i20.38713","type":"journal-article","created":{"date-parts":[[2026,3,18]],"date-time":"2026-03-18T00:49:39Z","timestamp":1773794979000},"page":"16709-16716","source":"Crossref","is-referenced-by-count":0,"title":["Understanding the Impact of Proportionality in Approval-Based Multiwinner Elections"],"prefix":"10.1609","volume":"40","author":[{"given":"Niclas","family":"Boehmer","sequence":"first","affiliation":[]},{"given":"Lara","family":"Glessen","sequence":"additional","affiliation":[]},{"given":"Jannik","family":"Peters","sequence":"additional","affiliation":[]}],"member":"9382","published-online":{"date-parts":[[2026,3,14]]},"container-title":["Proceedings of the AAAI Conference on Artificial Intelligence"],"original-title":[],"link":[{"URL":"https:\/\/ojs.aaai.org\/index.php\/AAAI\/article\/download\/38713\/42675","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/ojs.aaai.org\/index.php\/AAAI\/article\/download\/38713\/42675","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,3,18]],"date-time":"2026-03-18T00:49:39Z","timestamp":1773794979000},"score":1,"resource":{"primary":{"URL":"https:\/\/ojs.aaai.org\/index.php\/AAAI\/article\/view\/38713"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,3,14]]},"references-count":0,"journal-issue":{"issue":"20","published-online":{"date-parts":[[2026,3,17]]}},"URL":"https:\/\/doi.org\/10.1609\/aaai.v40i20.38713","relation":{},"ISSN":["2374-3468","2159-5399"],"issn-type":[{"value":"2374-3468","type":"electronic"},{"value":"2159-5399","type":"print"}],"subject":[],"published":{"date-parts":[[2026,3,14]]}}}