{"id":1607,"date":"2025-03-21T02:34:12","date_gmt":"2025-03-20T19:34:12","guid":{"rendered":"https:\/\/www.ckconitsha.com\/vn\/?p=1607"},"modified":"2025-06-13T11:09:06","modified_gmt":"2025-06-13T04:09:06","slug":"gia-tri-ngoai-le-cua-mau-so-lieu-la-gi","status":"publish","type":"post","link":"https:\/\/www.ckconitsha.com\/vn\/gia-tri-ngoai-le-cua-mau-so-lieu-la-gi\/","title":{"rendered":"Gi\u00e1 Tr\u1ecb Ngo\u1ea1i L\u1ec7 C\u1ee7a M\u1eabu S\u1ed1 Li\u1ec7u L\u00e0 G\u00ec?"},"content":{"rendered":"<div id=\"ez-toc-container\" class=\"ez-toc-v2_0_79_2 counter-hierarchy ez-toc-counter ez-toc-grey ez-toc-container-direction\">\n<div class=\"ez-toc-title-container\">\n<p class=\"ez-toc-title\" style=\"cursor:inherit\">Table of Contents<\/p>\n<span class=\"ez-toc-title-toggle\"><\/span><\/div>\n<nav><ul class='ez-toc-list ez-toc-list-level-1 ' ><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-1\" href=\"https:\/\/www.ckconitsha.com\/vn\/gia-tri-ngoai-le-cua-mau-so-lieu-la-gi\/#Gia_tri_ngoai_le_la_gi\" >Gi\u00e1 tr\u1ecb ngo\u1ea1i l\u1ec7 l\u00e0 g\u00ec?<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-2\" href=\"https:\/\/www.ckconitsha.com\/vn\/gia-tri-ngoai-le-cua-mau-so-lieu-la-gi\/#Cach_xac_dinh_gia_tri_ngoai_le\" >C\u00e1ch x\u00e1c \u0111\u1ecbnh gi\u00e1 tr\u1ecb ngo\u1ea1i l\u1ec7<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-3\" href=\"https:\/\/www.ckconitsha.com\/vn\/gia-tri-ngoai-le-cua-mau-so-lieu-la-gi\/#Su_dung_khoang_tu_phan_vi\" >S\u1eed d\u1ee5ng kho\u1ea3ng t\u1ee9 ph\u00e2n v\u1ecb<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-4\" href=\"https:\/\/www.ckconitsha.com\/vn\/gia-tri-ngoai-le-cua-mau-so-lieu-la-gi\/#Su_dung_bieu_do_hop_box_plot\" >S\u1eed d\u1ee5ng bi\u1ec3u \u0111\u1ed3 h\u1ed9p (box plot)<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-5\" href=\"https:\/\/www.ckconitsha.com\/vn\/gia-tri-ngoai-le-cua-mau-so-lieu-la-gi\/#Vi_du_minh_hoa\" >V\u00ed d\u1ee5 minh h\u1ecda<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-6\" href=\"https:\/\/www.ckconitsha.com\/vn\/gia-tri-ngoai-le-cua-mau-so-lieu-la-gi\/#Y_nghia_va_tac_dong_cua_gia_tri_ngoai_le\" >\u00dd ngh\u0129a v\u00e0 t\u00e1c \u0111\u1ed9ng c\u1ee7a gi\u00e1 tr\u1ecb ngo\u1ea1i l\u1ec7<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-7\" href=\"https:\/\/www.ckconitsha.com\/vn\/gia-tri-ngoai-le-cua-mau-so-lieu-la-gi\/#Xu_ly_gia_tri_ngoai_le\" >X\u1eed l\u00fd gi\u00e1 tr\u1ecb ngo\u1ea1i l\u1ec7<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-8\" href=\"https:\/\/www.ckconitsha.com\/vn\/gia-tri-ngoai-le-cua-mau-so-lieu-la-gi\/#Khoang_bien_thien\" >Kho\u1ea3ng bi\u1ebfn thi\u00ean<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-9\" href=\"https:\/\/www.ckconitsha.com\/vn\/gia-tri-ngoai-le-cua-mau-so-lieu-la-gi\/#Khoang_tu_phan_vi\" >Kho\u1ea3ng t\u1ee9 ph\u00e2n v\u1ecb<\/a><\/li><\/ul><\/nav><\/div>\n<h2><span class=\"ez-toc-section\" id=\"Gia_tri_ngoai_le_la_gi\"><\/span>Gi\u00e1 tr\u1ecb ngo\u1ea1i l\u1ec7 l\u00e0 g\u00ec?<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>Gi\u00e1 tr\u1ecb ngo\u1ea1i l\u1ec7 l\u00e0 nh\u1eefng gi\u00e1 tr\u1ecb n\u1eb1m xa so v\u1edbi ph\u1ea7n l\u1edbn d\u1eef li\u1ec7u trong m\u1ed9t m\u1eabu s\u1ed1 li\u1ec7u. Ch\u00fang c\u00f3 th\u1ec3 l\u00e0 nh\u1eefng \u0111i\u1ec3m d\u1eef li\u1ec7u b\u1ea5t th\u01b0\u1eddng, sai s\u00f3t trong qu\u00e1 tr\u00ecnh thu th\u1eadp ho\u1eb7c \u0111\u1ea1i di\u1ec7n cho m\u1ed9t hi\u1ec7n t\u01b0\u1ee3ng \u0111\u1eb7c bi\u1ec7t. Vi\u1ec7c x\u00e1c \u0111\u1ecbnh v\u00e0 x\u1eed l\u00fd gi\u00e1 tr\u1ecb ngo\u1ea1i l\u1ec7 r\u1ea5t quan tr\u1ecdng trong ph\u00e2n t\u00edch d\u1eef li\u1ec7u v\u00ec ch\u00fang c\u00f3 th\u1ec3 \u1ea3nh h\u01b0\u1edfng \u0111\u1ebfn k\u1ebft qu\u1ea3 th\u1ed1ng k\u00ea, g\u00e2y hi\u1ec3u l\u1ea7m v\u1ec1 xu h\u01b0\u1edbng chung c\u1ee7a d\u1eef li\u1ec7u.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"Cach_xac_dinh_gia_tri_ngoai_le\"><\/span>C\u00e1ch x\u00e1c \u0111\u1ecbnh gi\u00e1 tr\u1ecb ngo\u1ea1i l\u1ec7<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>C\u00f3 nhi\u1ec1u ph\u01b0\u01a1ng ph\u00e1p \u0111\u1ec3 x\u00e1c \u0111\u1ecbnh gi\u00e1 tr\u1ecb ngo\u1ea1i l\u1ec7, m\u1ed9t trong nh\u1eefng c\u00e1ch ph\u1ed5 bi\u1ebfn nh\u1ea5t l\u00e0 s\u1eed d\u1ee5ng kho\u1ea3ng t\u1ee9 ph\u00e2n v\u1ecb v\u00e0 bi\u1ec3u \u0111\u1ed3 h\u1ed9p (box plot).<\/p>\n<h3><span class=\"ez-toc-section\" id=\"Su_dung_khoang_tu_phan_vi\"><\/span>S\u1eed d\u1ee5ng kho\u1ea3ng t\u1ee9 ph\u00e2n v\u1ecb<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<ol>\n<li><strong>S\u1eafp x\u1ebfp d\u1eef li\u1ec7u:<\/strong> S\u1eafp x\u1ebfp m\u1eabu s\u1ed1 li\u1ec7u theo th\u1ee9 t\u1ef1 t\u0103ng d\u1ea7n.<\/li>\n<li><strong>T\u00ecm t\u1ee9 ph\u00e2n v\u1ecb:<\/strong> X\u00e1c \u0111\u1ecbnh Q1 (t\u1ee9 ph\u00e2n v\u1ecb th\u1ee9 nh\u1ea5t), Q2 (trung v\u1ecb) v\u00e0 Q3 (t\u1ee9 ph\u00e2n v\u1ecb th\u1ee9 ba).<\/li>\n<li><strong>T\u00ednh kho\u1ea3ng t\u1ee9 ph\u00e2n v\u1ecb (IQR):<\/strong> IQR = Q3 &#8211; Q1.<\/li>\n<li><strong>X\u00e1c \u0111\u1ecbnh gi\u1edbi h\u1ea1n tr\u00ean v\u00e0 gi\u1edbi h\u1ea1n d\u01b0\u1edbi:<\/strong>\n<ul>\n<li>Gi\u1edbi h\u1ea1n d\u01b0\u1edbi = Q1 &#8211; 1.5 * IQR<\/li>\n<li>Gi\u1edbi h\u1ea1n tr\u00ean = Q3 + 1.5 * IQR<\/li>\n<\/ul>\n<\/li>\n<li><strong>X\u00e1c \u0111\u1ecbnh gi\u00e1 tr\u1ecb ngo\u1ea1i l\u1ec7:<\/strong> B\u1ea5t k\u1ef3 gi\u00e1 tr\u1ecb n\u00e0o n\u1eb1m ngo\u00e0i gi\u1edbi h\u1ea1n tr\u00ean ho\u1eb7c d\u01b0\u1edbi \u0111\u1ec1u \u0111\u01b0\u1ee3c coi l\u00e0 gi\u00e1 tr\u1ecb ngo\u1ea1i l\u1ec7.<\/li>\n<\/ol>\n<h3><span class=\"ez-toc-section\" id=\"Su_dung_bieu_do_hop_box_plot\"><\/span>S\u1eed d\u1ee5ng bi\u1ec3u \u0111\u1ed3 h\u1ed9p (box plot)<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>Bi\u1ec3u \u0111\u1ed3 h\u1ed9p l\u00e0 m\u1ed9t c\u00e1ch tr\u1ef1c quan \u0111\u1ec3 x\u00e1c \u0111\u1ecbnh gi\u00e1 tr\u1ecb ngo\u1ea1i l\u1ec7.  C\u00e1c \u0111i\u1ec3m n\u1eb1m ngo\u00e0i &#8220;r\u00e2u&#8221; c\u1ee7a bi\u1ec3u \u0111\u1ed3 h\u1ed9p th\u01b0\u1eddng \u0111\u01b0\u1ee3c coi l\u00e0 gi\u00e1 tr\u1ecb ngo\u1ea1i l\u1ec7.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"Vi_du_minh_hoa\"><\/span>V\u00ed d\u1ee5 minh h\u1ecda<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>Gi\u1ea3 s\u1eed ta c\u00f3 m\u1eabu s\u1ed1 li\u1ec7u \u0111i\u1ec3m thi c\u1ee7a m\u1ed9t l\u1edbp h\u1ecdc: 5, 6, 7, 7, 8, 8, 8, 9, 9, 10, 15.<\/p>\n<ol>\n<li><strong>S\u1eafp x\u1ebfp:<\/strong> D\u1eef li\u1ec7u \u0111\u00e3 \u0111\u01b0\u1ee3c s\u1eafp x\u1ebfp.<\/li>\n<li><strong>T\u1ee9 ph\u00e2n v\u1ecb:<\/strong> Q1 = 7, Q2 = 8, Q3 = 9.<\/li>\n<li><strong>IQR:<\/strong> IQR = 9 &#8211; 7 = 2.<\/li>\n<li><strong>Gi\u1edbi h\u1ea1n:<\/strong>\n<ul>\n<li>Gi\u1edbi h\u1ea1n d\u01b0\u1edbi = 7 &#8211; 1.5 * 2 = 4<\/li>\n<li>Gi\u1edbi h\u1ea1n tr\u00ean = 9 + 1.5 * 2 = 12<\/li>\n<\/ul>\n<\/li>\n<li><strong>Gi\u00e1 tr\u1ecb ngo\u1ea1i l\u1ec7:<\/strong> Gi\u00e1 tr\u1ecb 15 n\u1eb1m ngo\u00e0i gi\u1edbi h\u1ea1n tr\u00ean, n\u00ean 15 l\u00e0 gi\u00e1 tr\u1ecb ngo\u1ea1i l\u1ec7.<\/li>\n<\/ol>\n<h2><span class=\"ez-toc-section\" id=\"Y_nghia_va_tac_dong_cua_gia_tri_ngoai_le\"><\/span>\u00dd ngh\u0129a v\u00e0 t\u00e1c \u0111\u1ed9ng c\u1ee7a gi\u00e1 tr\u1ecb ngo\u1ea1i l\u1ec7<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>Gi\u00e1 tr\u1ecb ngo\u1ea1i l\u1ec7 c\u00f3 th\u1ec3 cung c\u1ea5p th\u00f4ng tin h\u1eefu \u00edch v\u1ec1 hi\u1ec7n t\u01b0\u1ee3ng \u0111\u1eb7c bi\u1ec7t ho\u1eb7c sai s\u00f3t trong d\u1eef li\u1ec7u. Tuy nhi\u00ean, ch\u00fang c\u0169ng c\u00f3 th\u1ec3 l\u00e0m sai l\u1ec7ch k\u1ebft qu\u1ea3 th\u1ed1ng k\u00ea nh\u01b0 trung b\u00ecnh, \u0111\u1ed9 l\u1ec7ch chu\u1ea9n.  <\/p>\n<h2><span class=\"ez-toc-section\" id=\"Xu_ly_gia_tri_ngoai_le\"><\/span>X\u1eed l\u00fd gi\u00e1 tr\u1ecb ngo\u1ea1i l\u1ec7<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>Vi\u1ec7c x\u1eed l\u00fd gi\u00e1 tr\u1ecb ngo\u1ea1i l\u1ec7 ph\u1ee5 thu\u1ed9c v\u00e0o nguy\u00ean nh\u00e2n v\u00e0 m\u1ee5c ti\u00eau ph\u00e2n t\u00edch. M\u1ed9t s\u1ed1 ph\u01b0\u01a1ng ph\u00e1p x\u1eed l\u00fd bao g\u1ed3m:<\/p>\n<ul>\n<li><strong>Lo\u1ea1i b\u1ecf:<\/strong>  Lo\u1ea1i b\u1ecf gi\u00e1 tr\u1ecb ngo\u1ea1i l\u1ec7 n\u1ebfu ch\u00fang l\u00e0 do sai s\u00f3t trong qu\u00e1 tr\u00ecnh thu th\u1eadp d\u1eef li\u1ec7u.<\/li>\n<li><strong>Thay th\u1ebf:<\/strong> Thay th\u1ebf gi\u00e1 tr\u1ecb ngo\u1ea1i l\u1ec7 b\u1eb1ng gi\u00e1 tr\u1ecb kh\u00e1c, v\u00ed d\u1ee5 nh\u01b0 gi\u00e1 tr\u1ecb trung b\u00ecnh ho\u1eb7c trung v\u1ecb.<\/li>\n<li><strong>Gi\u1eef nguy\u00ean:<\/strong>  Gi\u1eef nguy\u00ean gi\u00e1 tr\u1ecb ngo\u1ea1i l\u1ec7 n\u1ebfu ch\u00fang \u0111\u1ea1i di\u1ec7n cho m\u1ed9t hi\u1ec7n t\u01b0\u1ee3ng th\u1ef1c t\u1ebf v\u00e0 c\u00f3 \u00fd ngh\u0129a \u0111\u1ed1i v\u1edbi ph\u00e2n t\u00edch.<\/li>\n<li><strong>Ph\u00e2n t\u00edch ri\u00eang:<\/strong> Ph\u00e2n t\u00edch gi\u00e1 tr\u1ecb ngo\u1ea1i l\u1ec7 ri\u00eang bi\u1ec7t \u0111\u1ec3 hi\u1ec3u r\u00f5 h\u01a1n v\u1ec1 nguy\u00ean nh\u00e2n v\u00e0 t\u00e1c \u0111\u1ed9ng c\u1ee7a ch\u00fang.<\/li>\n<\/ul>\n<h2><span class=\"ez-toc-section\" id=\"Khoang_bien_thien\"><\/span>Kho\u1ea3ng bi\u1ebfn thi\u00ean<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>Kho\u1ea3ng bi\u1ebfn thi\u00ean (R) l\u00e0 hi\u1ec7u s\u1ed1 gi\u1eefa gi\u00e1 tr\u1ecb l\u1edbn nh\u1ea5t v\u00e0 gi\u00e1 tr\u1ecb nh\u1ecf nh\u1ea5t trong m\u1eabu s\u1ed1 li\u1ec7u.  R = Gi\u00e1 tr\u1ecb l\u1edbn nh\u1ea5t &#8211; Gi\u00e1 tr\u1ecb nh\u1ecf nh\u1ea5t.  V\u00ed d\u1ee5, trong m\u1eabu s\u1ed1 li\u1ec7u tr\u00ean, R = 15 &#8211; 5 = 10.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"Khoang_tu_phan_vi\"><\/span>Kho\u1ea3ng t\u1ee9 ph\u00e2n v\u1ecb<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>Kho\u1ea3ng t\u1ee9 ph\u00e2n v\u1ecb (IQR) \u0111\u00e3 \u0111\u01b0\u1ee3c gi\u1ea3i th\u00edch \u1edf tr\u00ean.  IQR l\u00e0 m\u1ed9t th\u01b0\u1edbc \u0111o \u0111\u1ed9 ph\u00e2n t\u00e1n c\u1ee7a d\u1eef li\u1ec7u, \u00edt b\u1ecb \u1ea3nh h\u01b0\u1edfng b\u1edfi gi\u00e1 tr\u1ecb ngo\u1ea1i l\u1ec7 h\u01a1n so v\u1edbi kho\u1ea3ng bi\u1ebfn thi\u00ean.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Gi\u00e1 tr\u1ecb ngo\u1ea1i l\u1ec7 l\u00e0 g\u00ec? Gi\u00e1 tr\u1ecb ngo\u1ea1i l\u1ec7 l\u00e0 nh\u1eefng gi\u00e1 tr\u1ecb n\u1eb1m xa so v\u1edbi ph\u1ea7n l\u1edbn d\u1eef li\u1ec7u trong m\u1ed9t m\u1eabu s\u1ed1 li\u1ec7u. Ch\u00fang c\u00f3 th\u1ec3 l\u00e0 nh\u1eefng \u0111i\u1ec3m d\u1eef li\u1ec7u b\u1ea5t th\u01b0\u1eddng, sai s\u00f3t trong qu\u00e1 tr\u00ecnh thu th\u1eadp ho\u1eb7c \u0111\u1ea1i di\u1ec7n cho m\u1ed9t hi\u1ec7n t\u01b0\u1ee3ng \u0111\u1eb7c bi\u1ec7t. Vi\u1ec7c x\u00e1c&#8230;<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-1607","post","type-post","status-publish","format-standard","hentry","category-blog"],"_links":{"self":[{"href":"https:\/\/www.ckconitsha.com\/vn\/wp-json\/wp\/v2\/posts\/1607","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.ckconitsha.com\/vn\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.ckconitsha.com\/vn\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.ckconitsha.com\/vn\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.ckconitsha.com\/vn\/wp-json\/wp\/v2\/comments?post=1607"}],"version-history":[{"count":1,"href":"https:\/\/www.ckconitsha.com\/vn\/wp-json\/wp\/v2\/posts\/1607\/revisions"}],"predecessor-version":[{"id":1608,"href":"https:\/\/www.ckconitsha.com\/vn\/wp-json\/wp\/v2\/posts\/1607\/revisions\/1608"}],"wp:attachment":[{"href":"https:\/\/www.ckconitsha.com\/vn\/wp-json\/wp\/v2\/media?parent=1607"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.ckconitsha.com\/vn\/wp-json\/wp\/v2\/categories?post=1607"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.ckconitsha.com\/vn\/wp-json\/wp\/v2\/tags?post=1607"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}