{"id":7229,"date":"2026-09-16T18:29:06","date_gmt":"2026-09-16T18:29:06","guid":{"rendered":"http:\/\/french.arabpsychology.com\/statistics\/variance-combinee-definition-exemple\/"},"modified":"2026-09-16T18:29:06","modified_gmt":"2026-09-16T18:29:06","slug":"variance-combinee-definition-exemple","status":"publish","type":"psych_stat","link":"https:\/\/french.arabpsychology.com\/?psych_stat=variance-combinee-definition-exemple","title":{"rendered":"Qu&rsquo;est-ce que la variance combin\u00e9e ? (D\u00e9finition et exemple)"},"content":{"rendered":"<p>r<br \/>\n# D\u00e9finition des donn\u00e9es empiriques de l&rsquo;exemple clinique<br \/>\nn1 <- 25; m1 <- 42.0; s1 <- 6.0\nn2 <- 20; m2 <- 47.0; s2 <- 7.0\n\n# 1. Calcul de la variance combin\u00e9e et de l'\u00e9cart-type combin\u00e9\nsp_carre <- ((n1 - 1) * s1^2 + (n2 - 1) * s2^2) \/ (n1 + n2 - 2)\nsp <- sqrt(sp_carre)\ncat(\"Variance combin\u00e9e (sp2) :\", round(sp_carre, 4), \"n\")\ncat(\"\u00c9cart-type combin\u00e9 (sp)  :\", round(sp, 4), \"n\")\n\n# 2. Simulation de vecteurs pour t.test direct\nset.seed(123)\ngroupe1 <- rnorm(n1, mean = m1, sd = s1)\ngroupe2 <- rnorm(n2, mean = m2, sd = s2)\n\n# 3. Ex\u00e9cution du test t avec variance combin\u00e9e\nresultat_t <- t.test(groupe1, groupe2, var.equal = TRUE)\nprint(resultat_t)\n<\/p>\n","protected":false},"excerpt":{"rendered":"<p>D\u00e9couvrez la d\u00e9finition, la formule math\u00e9matique et des exemples concrets de la variance combin\u00e9e (pooled variance) en statistiques et recherche psychologique.<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"closed","template":"","categories":[304,1835],"tags":[2546,2461,16,3321,5809],"class_list":["post-7229","psych_stat","type-psych_stat","status-publish","hentry","category-methodologie-de-recherche","category-statistiques-en-psychologie","tag-d-de-cohen","tag-homoscedasticite","tag-psychometrie","tag-test-t-de-student","tag-variance-combinee"],"_links":{"self":[{"href":"https:\/\/french.arabpsychology.com\/index.php?rest_route=\/wp\/v2\/psych_stat\/7229","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/french.arabpsychology.com\/index.php?rest_route=\/wp\/v2\/psych_stat"}],"about":[{"href":"https:\/\/french.arabpsychology.com\/index.php?rest_route=\/wp\/v2\/types\/psych_stat"}],"author":[{"embeddable":true,"href":"https:\/\/french.arabpsychology.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/french.arabpsychology.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=7229"}],"version-history":[{"count":0,"href":"https:\/\/french.arabpsychology.com\/index.php?rest_route=\/wp\/v2\/psych_stat\/7229\/revisions"}],"wp:attachment":[{"href":"https:\/\/french.arabpsychology.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=7229"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/french.arabpsychology.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=7229"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/french.arabpsychology.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=7229"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}