{"id":137,"date":"2019-01-05T19:55:31","date_gmt":"2019-01-05T18:55:31","guid":{"rendered":"http:\/\/excelop.net\/exo\/?p=137"},"modified":"2020-02-27T23:03:11","modified_gmt":"2020-02-27T22:03:11","slug":"etude-de-cas-1","status":"publish","type":"post","link":"https:\/\/excelop.net\/exo\/etude-de-cas-1\/","title":{"rendered":"Etude de cas 1"},"content":{"rendered":"\n<p class=\"wp-block-paragraph\">&nbsp;Imaginons un \u00e9leveur qui souhaite acheter de nouvelles vaches pour sa production laiti\u00e8re. Il poss\u00e8de trois races diff\u00e9rentes de vaches et se pose donc la question de savoir si la race est importante pour son choix. Il poss\u00e8de comme informations la race de chacune de ses b\u00eates (c&#8217;est la variable explicative discr\u00e8te ou&nbsp;facteur de variabilit\u00e9, qui peut prendre 3 valeurs diff\u00e9rentes) et leurs productions de lait journali\u00e8res (c&#8217;est la variable \u00e0 expliquer continue, qui correspond au volume de lait en litre).<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Dans notre exemple, l&#8217;hypoth\u00e8se nulle revient \u00e0 consid\u00e9rer que toutes les vaches produisent la m\u00eame quantit\u00e9 de lait journali\u00e8re (au facteur al\u00e9atoire pr\u00e8s) quelle que soit la race. L&#8217;hypoth\u00e8se alternative revient \u00e0 consid\u00e9rer qu&#8217;une des races produit significativement plus ou moins de lait que les autres.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Supposons que les productions soient&nbsp;:<\/p>\n\n\n\n<ul class=\"wp-block-list\"><li>Pour la race A&nbsp;: 20,1&nbsp;; 19,8&nbsp;; 21,3 et 20,7<\/li><li>Pour la race B&nbsp;: 22,6&nbsp;; 24,1&nbsp;; 23,8&nbsp;; 22,5&nbsp;; 23,4&nbsp;; 24,5 et 22,9<\/li><li>Pour la race C&nbsp;: 31,2&nbsp;; 31,6&nbsp;; 31,0&nbsp;; 32,1 et 31,4<\/li><\/ul>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"\"><tbody><tr><th>Race<\/th><th>Taille<\/th><th>Moyenne<\/th><th>Variance<\/th><\/tr><tr><td>A<\/td><td>4<\/td><td>20,475<\/td><td>0,443<\/td><\/tr><tr><td>B<\/td><td>7<\/td><td>23,4<\/td><td>0,59333<\/td><\/tr><tr><td>C<\/td><td>5<\/td><td>31,46<\/td><td>0,178<\/td><\/tr><tr><td>Total<\/td><td>16<\/td><td>25,1875<\/td><td>20,90117<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Table d&#8217;ANOVA<\/strong>&nbsp;:<br><\/p>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"\"><tbody><tr><th>Source de la variance<\/th><th>Sommes des<br>carr\u00e9s des \u00e9carts<\/th><th>Degr\u00e9s de libert\u00e9<\/th><th>Variance<\/th><th>F<\/th><th>p-value<\/th><\/tr><tr><td>Inter-classes<\/td><td>307,918<\/td><td>2<\/td><td>153,959<\/td><td>357,44<\/td><td>4,338 e-12<\/td><\/tr><tr><td>Intra-classe<\/td><td>5,6<\/td><td>13<\/td><td>0,431<\/td><\/tr><\/tbody><\/table><\/figure>\n","protected":false},"excerpt":{"rendered":"<p>&nbsp;Imaginons un \u00e9leveur qui souhaite acheter de nouvelles vaches pour sa production laiti\u00e8re. Il poss\u00e8de trois races diff\u00e9rentes de vaches et se pose donc la question de savoir si la race est importante pour son choix. Il poss\u00e8de comme informations la race de chacune de ses b\u00eates (c&#8217;est la variable explicative discr\u00e8te ou&nbsp;facteur de variabilit\u00e9, [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_crdt_document":"","footnotes":""},"categories":[1],"tags":[],"class_list":["post-137","post","type-post","status-publish","format-standard","hentry","category-non-classe"],"_links":{"self":[{"href":"https:\/\/excelop.net\/exo\/wp-json\/wp\/v2\/posts\/137","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/excelop.net\/exo\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/excelop.net\/exo\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/excelop.net\/exo\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/excelop.net\/exo\/wp-json\/wp\/v2\/comments?post=137"}],"version-history":[{"count":3,"href":"https:\/\/excelop.net\/exo\/wp-json\/wp\/v2\/posts\/137\/revisions"}],"predecessor-version":[{"id":449,"href":"https:\/\/excelop.net\/exo\/wp-json\/wp\/v2\/posts\/137\/revisions\/449"}],"wp:attachment":[{"href":"https:\/\/excelop.net\/exo\/wp-json\/wp\/v2\/media?parent=137"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/excelop.net\/exo\/wp-json\/wp\/v2\/categories?post=137"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/excelop.net\/exo\/wp-json\/wp\/v2\/tags?post=137"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}