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The main ones concern equilibrium uniqueness. The setting presupposes that each player has <jats:inline-formula><jats:alternatives><jats:tex-math>$$\\mathbb {R}_+$$<\/jats:tex-math><mml:math xmlns:mml=\"http:\/\/www.w3.org\/1998\/Math\/MathML\">\n                  <mml:msub>\n                    <mml:mi>R<\/mml:mi>\n                    <mml:mo>+<\/mml:mo>\n                  <\/mml:msub>\n                <\/mml:math><\/jats:alternatives><\/jats:inline-formula> as strategy set, makes smoothness assumptions but allows for a discontinuity of stand-alone payoff functions at 0; this possibility is especially important for various contest and oligopolistic games. Conditions are completely in terms of marginal reductions which may be considered as primitives of the game. For many games in the literature they can easily be checked. They automatically imply that conditional payoff functions are strictly quasi-concave. The results are proved by means of the Szidarovszky variant of the Selten\u2013Szidarovszky technique. Their power is illustrated by reproducing quickly and improving upon various results for economic games.<\/jats:p>","DOI":"10.1007\/s11590-021-01780-7","type":"journal-article","created":{"date-parts":[[2021,7,20]],"date-time":"2021-07-20T03:32:11Z","timestamp":1626751931000},"page":"2033-2058","update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Equilibrium uniqueness in aggregative games: very practical conditions"],"prefix":"10.1007","volume":"16","author":[{"given":"Jun-ichi","family":"Itaya","sequence":"first","affiliation":[]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5702-3340","authenticated-orcid":false,"given":"Pierre","family":"von Mouche","sequence":"additional","affiliation":[]}],"member":"297","published-online":{"date-parts":[[2021,7,20]]},"reference":[{"key":"1780_CR1","doi-asserted-by":"publisher","first-page":"27","DOI":"10.1016\/j.geb.2013.03.009","volume":"81","author":"D Acemoglu","year":"2013","unstructured":"Acemoglu, D., Jensen, M.K.: Aggregate comparative statics. 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