{"id":8596,"date":"2026-10-06T09:00:00","date_gmt":"2026-10-06T07:00:00","guid":{"rendered":"https:\/\/smalltalks.eu\/blog\/?p=8596"},"modified":"2026-11-08T13:02:49","modified_gmt":"2026-11-08T12:02:49","slug":"un-jeu-equitable-qui-fabrique-99-de-pauvres-matthias-chemla","status":"publish","type":"post","link":"https:\/\/smalltalks.eu\/blog\/2026\/10\/06\/un-jeu-equitable-qui-fabrique-99-de-pauvres-matthias-chemla\/","title":{"rendered":"Un jeu \u00e9quitable qui fabrique 99 % de pauvres (Matthias Chemla)"},"content":{"rendered":"\n<figure class=\"wp-block-embed is-type-video is-provider-youtube wp-block-embed-youtube wp-embed-aspect-16-9 wp-has-aspect-ratio\"><div class=\"wp-block-embed__wrapper\">\n<iframe loading=\"lazy\" title=\"Ce jeu est \u00e9quitable. Pourquoi produit-il 99% de pauvres ?\" width=\"640\" height=\"360\" src=\"https:\/\/www.youtube.com\/embed\/CXjc7GGXsVw?feature=oembed\" frameborder=\"0\" allow=\"accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share\" referrerpolicy=\"strict-origin-when-cross-origin\" allowfullscreen><\/iframe>\n<\/div><\/figure>\n\n\n\n<div style=\"height:30px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n<p class=\"wp-block-paragraph\">Cent joueurs, cent euros chacun, une pi\u00e8ce bien \u00e9quilibr\u00e9e. \u00c0 chaque tour, deux joueurs tir\u00e9s au hasard jouent \u00e0 pile ou face 10 % de la fortune du plus pauvre des deux. Le jeu est parfaitement \u00e9quitable, et pourtant, \u00e0 la longue, presque tout l&#8217;argent finit chez un seul joueur.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">C&#8217;est le mod\u00e8le dit du \u00ab vide-grenier \u00bb (<em>Yard-Sale<\/em>). Matthias Chemla le simule, puis l&#8217;explique : la fortune moyenne reste \u00e0 cent euros, mais presque tous les joueurs s&#8217;appauvrissent ; la d\u00e9monstration passe par les martingales et le th\u00e9or\u00e8me de Doob. Il teste enfin une r\u00e8gle de redistribution, pour voir ce que changent les r\u00e8gles du jeu.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Voir aussi : <a href=\"https:\/\/smalltalks.eu\/blog\/?p=8252\">les chiffres des in\u00e9galit\u00e9s (\u00c9lucid)<\/a>, <a href=\"https:\/\/smalltalks.eu\/blog\/?p=8353\">le meilleur moyen de rouler un pauvre<\/a>.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><em>Cha\u00eene Matthias Chemla.<\/em><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Cent joueurs, cent euros chacun, une pi\u00e8ce bien \u00e9quilibr\u00e9e. \u00c0 chaque tour, deux joueurs tir\u00e9s au hasard jouent \u00e0 pile ou face 10 % de la fortune du plus pauvre des deux. Le jeu est parfaitement \u00e9quitable, et pourtant, \u00e0 la longue, presque tout l&#8217;argent finit chez un seul joueur. C&#8217;est le mod\u00e8le dit du \u00ab vide-grenier \u00bb (Yard-Sale). Matthias Chemla le simule, puis l&#8217;explique : la fortune moyenne reste \u00e0 cent euros, mais presque tous les joueurs s&#8217;appauvrissent ;&#8230;<\/p>\n<p class=\"read-more\"><a class=\"btn btn-default\" href=\"https:\/\/smalltalks.eu\/blog\/2026\/10\/06\/un-jeu-equitable-qui-fabrique-99-de-pauvres-matthias-chemla\/\"> Read More<span class=\"screen-reader-text\">  Read More<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[280,282,38],"tags":[],"class_list":["post-8596","post","type-post","status-publish","format-standard","hentry","category-sciences","category-sciences-mathematiques","category-theme-economie-mondiale"],"_links":{"self":[{"href":"https:\/\/smalltalks.eu\/blog\/wp-json\/wp\/v2\/posts\/8596","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/smalltalks.eu\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/smalltalks.eu\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/smalltalks.eu\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/smalltalks.eu\/blog\/wp-json\/wp\/v2\/comments?post=8596"}],"version-history":[{"count":1,"href":"https:\/\/smalltalks.eu\/blog\/wp-json\/wp\/v2\/posts\/8596\/revisions"}],"predecessor-version":[{"id":8602,"href":"https:\/\/smalltalks.eu\/blog\/wp-json\/wp\/v2\/posts\/8596\/revisions\/8602"}],"wp:attachment":[{"href":"https:\/\/smalltalks.eu\/blog\/wp-json\/wp\/v2\/media?parent=8596"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/smalltalks.eu\/blog\/wp-json\/wp\/v2\/categories?post=8596"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/smalltalks.eu\/blog\/wp-json\/wp\/v2\/tags?post=8596"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}