{"id":21755,"date":"2023-12-06T02:54:03","date_gmt":"2023-12-06T02:54:03","guid":{"rendered":"https:\/\/masterskills.org\/blog\/coefficient-of-variation-la-gi-vai-tro-va-uu-nhuoc-diem.html"},"modified":"2023-12-22T04:56:14","modified_gmt":"2023-12-21T21:56:14","slug":"coefficient-of-variation-la-gi-vai-tro-va-uu-nhuoc-diem","status":"publish","type":"post","link":"https:\/\/masterskills.org\/blog\/coefficient-of-variation-la-gi-vai-tro-va-uu-nhuoc-diem.html","title":{"rendered":"Coefficient of Variation l\u00e0 g\u00ec? Vai tr\u00f2 v\u00e0 \u01b0u, nh\u01b0\u1ee3c \u0111i\u1ec3m"},"content":{"rendered":"<div class=\"entry-content\">\n<figure class=\"wp-block-image size-large\"><\/figure>\n<p>H\u1ec7 s\u1ed1 bi\u1ebfn thi\u00ean \u2013 <strong>Coefficient of Variation<\/strong> l\u00e0 g\u00ec? \u0110\u00e2y l\u00e0 m\u1ed9t th\u00f4ng s\u1ed1 quan tr\u1ecdng trong l\u0129nh v\u1ef1c to\u00e1n th\u1ed1ng k\u00ea. H\u1ec7 s\u1ed1 bi\u1ebfn thi\u00ean \u0111\u01b0\u1ee3c \u1ee9ng d\u1ee5ng \u1edf nhi\u1ec1u kh\u00eda c\u1ea1nh kh\u00e1c nhau c\u1ee7a cu\u1ed9c s\u1ed1ng, c\u1ea3 trong to\u00e1n h\u1ecdc, sinh h\u1ecdc, y d\u01b0\u1ee3c, t\u00e0i ch\u00ednh v\u00e0 \u0111\u1ea7u t\u01b0 ch\u1ee9ng kho\u00e1n\u2026 Th\u1ef1c ch\u1ea5t Coefficient of Variation l\u00e0 g\u00ec? \u01afu, nh\u01b0\u1ee3c \u0111i\u1ec3m l\u00e0 g\u00ec? C\u00e1ch \u1ee9ng d\u1ee5ng h\u1ec7 s\u1ed1 bi\u1ebfn thi\u00ean trong \u0111\u1ea7u t\u01b0 ra sao? D\u01b0\u1edbi \u0111\u00e2y l\u00e0 c\u00e2u tr\u1ea3 l\u1eddi d\u00e0nh cho b\u1ea1n.<\/p>\n<h2><span id=\"Coefficient_of_Variation_la_gi\"><strong>Coefficient of Variation l\u00e0 g\u00ec?<\/strong><\/span><\/h2>\n<p>Coefficient of Variation trong ti\u1ebfng Anh c\u00f3 ngh\u0129a l\u00e0 h\u1ec7 s\u1ed1 bi\u1ebfn thi\u00ean.<\/p>\n<p>H\u1ec7 s\u1ed1 bi\u1ebfn thi\u00ean\u00a0(Coefficient of Variation \u2013 CV) l\u00e0 m\u1ed9t \u0111\u1ea1i l\u01b0\u1ee3ng\u00a0th\u1ed1ng k\u00ea m\u00f4 t\u1ea3\u00a0c\u01a1 b\u1ea3n. H\u1ec7 s\u1ed1 n\u00e0y \u0111\u01b0\u1ee3c d\u00f9ng \u0111\u1ec3 \u0111o m\u1ee9c \u0111\u1ed9\u00a0bi\u1ebfn \u0111\u1ed9ng t\u01b0\u01a1ng \u0111\u1ed1i c\u1ee7a nh\u1eefng\u00a0t\u1eadp h\u1ee3p\u00a0d\u1eef li\u1ec7u\u00a0ch\u01b0a ph\u00e2n t\u1ed5 c\u00f3\u00a0gi\u00e1 tr\u1ecb b\u00ecnh qu\u00e2n\u00a0kh\u00e1c nhau. Kh\u00f4ng gi\u1ed1ng nh\u01b0 \u0111\u1ed9 l\u1ec7ch chu\u1ea9n lu\u00f4n ph\u1ea3i \u0111\u01b0\u1ee3c xem x\u00e9t trong b\u1ed1i c\u1ea3nh gi\u00e1 tr\u1ecb trung b\u00ecnh c\u1ee7a d\u1eef li\u1ec7u, h\u1ec7 s\u1ed1 bi\u1ebfn thi\u00ean cung c\u1ea5p m\u1ed9t c\u00f4ng c\u1ee5 t\u01b0\u01a1ng \u0111\u1ed1i \u0111\u01a1n gi\u1ea3n v\u00e0 nhanh ch\u00f3ng \u0111\u1ec3 so s\u00e1nh c\u00e1c chu\u1ed7i d\u1eef li\u1ec7u kh\u00e1c nhau.<\/p>\n<p>X\u00e9t v\u1ec1 b\u1ea3n ch\u1ea5t, h\u1ec7 s\u1ed1 bi\u1ebfn thi\u00ean ch\u00ednh l\u00e0 t\u1ec9 l\u1ec7 gi\u1eefa \u0111\u1ed9 l\u1ec7ch chu\u1ea9n (standard deviation) so v\u1edbi gi\u00e1 tr\u1ecb trung b\u00ecnh (mean). Do \u0111\u00f3, ng\u01b0\u1eddi ta t\u00ednh to\u00e1n CV b\u1eb1ng c\u00e1ch l\u1ea5y \u0111\u1ed9 l\u1ec7ch chu\u1ea9n chia cho gi\u00e1 tr\u1ecb trung b\u00ecnh. Khi \u0111em so s\u00e1nh gi\u1eefa 2 t\u1eadp h\u1ee3p d\u1eef li\u1ec7u, t\u1eadp h\u1ee3p n\u00e0o c\u00f3 h\u1ec7 s\u1ed1 bi\u1ebfn thi\u00ean l\u1edbn h\u01a1n ngh\u0129a l\u00e0 t\u1eadp h\u1ee3p \u0111\u00f3 c\u00f3 m\u1ee9c \u0111\u1ed9 bi\u1ebfn \u0111\u1ed9ng l\u1edbn h\u01a1n. Nh\u01b0 v\u1eady, c\u00f3 th\u1ec3 \u0111\u00e1nh gi\u00e1 Coefficient of Variation l\u00e0 m\u1ed9t th\u00f4ng s\u1ed1 th\u1ed1ng k\u00ea h\u1eefu \u00edch trong vi\u1ec7c so s\u00e1nh m\u1ee9c \u0111\u1ed9 bi\u1ebfn thi\u00ean c\u1ee7a chu\u1ed7i d\u1eef li\u1ec7u n\u00e0y v\u1edbi chu\u1ed7i d\u1eef li\u1ec7u kh\u00e1c, d\u00f9 cho gi\u00e1 tr\u1ecb trung b\u00ecnh c\u1ee7a c\u00e1c chu\u1ed7i d\u1eef li\u1ec7u r\u1ea5t kh\u00e1c nhau.<\/p>\n<blockquote>\n<p><strong><em>B\u1eb1ng c\u00e1ch x\u00e1c \u0111\u1ecbnh h\u1ec7 s\u1ed1 bi\u1ebfn thi\u00ean c\u1ee7a c\u00e1c ch\u1ee9ng kho\u00e1n kh\u00e1c nhau, nh\u00e0 \u0111\u1ea7u t\u01b0 x\u00e1c \u0111\u1ecbnh t\u1ef7 l\u1ec7 r\u1ee7i ro tr\u00ean l\u1ee3i nhu\u1eadn c\u1ee7a t\u1eebng ch\u1ee9ng kho\u00e1n v\u00e0 \u0111\u01b0a ra quy\u1ebft \u0111\u1ecbnh \u0111\u1ea7u t\u01b0.<\/em><\/strong><\/p>\n<\/blockquote>\n<h2><span id=\"Uu_nhuoc_diem_cua_Coefficient_of_Variation_la_gi\"><strong>\u01afu nh\u01b0\u1ee3c \u0111i\u1ec3m c\u1ee7a Coefficient of Variation l\u00e0 g\u00ec?<\/strong><\/span><\/h2>\n<p>Khi xem x\u00e9t kh\u00e1i ni\u1ec7m Coefficient of Variation l\u00e0 g\u00ec, ch\u00fang ta d\u1ec5 d\u00e0ng nh\u1eadn ra \u01b0u \u0111i\u1ec3m l\u1edbn nh\u1ea5t c\u1ee7a h\u1ec7 s\u1ed1 bi\u1ebfn thi\u00ean ch\u00ednh l\u00e0 c\u00f3 th\u1ec3 d\u00f9ng \u0111\u1ec3 so s\u00e1nh m\u1ee9c \u0111\u1ed9 bi\u1ebfn \u0111\u1ed9ng c\u1ee7a 2 t\u1eadp d\u1eef li\u1ec7u c\u00f3 gi\u00e1 tr\u1ecb b\u00ecnh qu\u00e2n kh\u00e1c nhau. Tuy nhi\u00ean, c\u0169ng ch\u00ednh v\u00ec \u0111\u1eb7c tr\u01b0ng c\u1ee7a h\u1ec7 s\u1ed1 bi\u1ebfn thi\u00ean l\u00e0 \u0111o m\u1ee9c \u0111\u1ed9 bi\u1ebfn \u0111\u1ed9ng n\u00ean trong tr\u01b0\u1eddng h\u1ee3p gi\u00e1 tr\u1ecb b\u00ecnh qu\u00e2n r\u1ea5t nh\u1ecf (g\u1ea7n b\u1eb1ng 0) th\u00ec ch\u1ec9 m\u1ed9t bi\u1ebfn \u0111\u1ed9ng nh\u1ecf c\u1ee7a gi\u00e1 tr\u1ecb b\u00ecnh qu\u00e2n c\u0169ng c\u00f3 th\u1ec3 khi\u1ebfn cho h\u1ec7 s\u1ed1 n\u00e0y thay \u0111\u1ed5i r\u1ea5t l\u1edbn. \u0110\u00e2y c\u0169ng ch\u00ednh l\u00e0 nh\u01b0\u1ee3c \u0111i\u1ec3m ph\u1ea3i k\u1ec3 \u0111\u1ebfn c\u1ee7a h\u1ec7 s\u1ed1 Coefficient of Variation.<\/p>\n<h2><span id=\"Hieu_the_nao_ve_Coefficient_of_Variation_trong_linh_vuc_tai_chinh\"><strong>Hi\u1ec3u th\u1ebf n\u00e0o v\u1ec1 Coefficient of Variation trong l\u0129nh v\u1ef1c t\u00e0i ch\u00ednh?<\/strong><\/span><\/h2>\n<p>Khi t\u00ecm hi\u1ec3u \u0111\u1ecbnh ngh\u0129a chung Coefficient of Variation l\u00e0 g\u00ec, ta bi\u1ebft r\u1eb1ng \u0111\u00e2y l\u00e0 h\u1ec7 s\u1ed1 bi\u1ebfn thi\u00ean\u00a0\u2013 m\u1ed9t th\u00f4ng s\u1ed1 cho th\u1ea5y m\u1ee9c \u0111\u1ed9 bi\u1ebfn thi\u00ean c\u1ee7a d\u1eef li\u1ec7u trong t\u01b0\u01a1ng quan v\u1edbi gi\u00e1 tr\u1ecb trung b\u00ecnh c\u1ee7a t\u1ed5ng th\u1ec3. Trong l\u0129nh v\u1ef1c t\u00e0i ch\u00ednh, Coefficient of Variation l\u00e0 th\u00f4ng s\u1ed1 bi\u1ec3u th\u1ecb m\u1ee9c \u0111\u1ed9 dao \u0111\u1ed9ng c\u1ee7a c\u00e1c s\u1ea3n ph\u1ea9m t\u00e0i ch\u00ednh (c\u1ed5 phi\u1ebfu, tr\u00e1i phi\u1ebfu, ti\u1ec1n t\u1ec7\u2026) tr\u00ean s\u00e0n ch\u1ee9ng kho\u00e1n.<\/p>\n<p>Nh\u00e0 \u0111\u1ea7u c\u00f3 th\u1ec3 \u1ee9ng d\u1ee5ng h\u1ec7 s\u1ed1 bi\u1ebfn thi\u00ean \u0111\u1ec3 x\u00e1c \u0111\u1ecbnh \u0111\u1ed9 l\u1ec7ch gi\u1eefa gi\u00e1 trung b\u00ecnh trong qu\u00e1 kh\u1ee9 v\u00e0 hi\u1ec7u su\u1ea5t gi\u00e1 hi\u1ec7n t\u1ea1i c\u1ee7a c\u1ed5 phi\u1ebfu, h\u00e0ng h\u00f3a ho\u1eb7c tr\u00e1i phi\u1ebfu so v\u1edbi c\u00e1c t\u00e0i s\u1ea3n kh\u00e1c. Th\u00f4ng qua Coefficient of Variation, nh\u00e0 \u0111\u1ea7u t\u01b0 c\u00f3 th\u1ec3 x\u00e1c \u0111\u1ecbnh \u0111\u01b0\u1ee3c m\u1ee9c \u0111\u1ed9 r\u1ee7i ro ho\u1eb7c l\u1ee3i nhu\u1eadn k\u1ef3 v\u1ecdng c\u1ee7a c\u00e1c kho\u1ea3n \u0111\u1ea7u t\u01b0. T\u1eeb \u0111\u00f3 h\u1ecd l\u1ea5y l\u00e0m c\u0103n c\u1ee9 \u0111\u1ec3 \u0111\u01b0a ra quy\u1ebft \u0111\u1ecbnh \u0111\u1ea7u t\u01b0 \u0111\u00fang \u0111\u1eafn.<\/p>\n<p>L\u00fd t\u01b0\u1edfng nh\u1ea5t, n\u1ebfu h\u1ec7 s\u1ed1 bi\u1ebfn thi\u00ean th\u1ea5p (ngh\u0129a l\u00e0 \u0111\u1ed9 l\u1ec7ch th\u1ea5p h\u01a1n nhi\u1ec1u so v\u1edbi gi\u00e1 tr\u1ecb trung b\u00ecnh) th\u00ec \u0111\u00e2y l\u00e0 d\u1ea5u hi\u1ec7u cho th\u1ea5y c\u01a1 h\u1ed9i \u0111\u1ea7u t\u01b0 h\u1ea5p d\u1eabn v\u00ec t\u1ec9 l\u1ec7 r\u1ee7i ro kh\u00f4ng cao. L\u01b0u \u00fd l\u00e0 n\u1ebfu l\u1ee3i nhu\u1eadn k\u00ec v\u1ecdng n\u1eb1m \u1edf m\u1eabu s\u1ed1 c\u00f3 gi\u00e1 tr\u1ecb \u00e2m ho\u1eb7c b\u1eb1ng th\u00ec h\u1ec7 s\u1ed1 bi\u1ebfn thi\u00ean c\u00f3 th\u1ec3 v\u00f4 ngh\u0129a, g\u00e2y hi\u1ec3u nh\u1ea7m.<\/p>\n<p>M\u1eb7t kh\u00e1c, h\u1ec7 s\u1ed1 Coefficient of Variation c\u00f2n h\u1eefu \u00edch khi nh\u00e0 \u0111\u1ea7u t\u01b0 s\u1eed d\u1ee5ng t\u1ec9 l\u1ec7 r\u1ee7i ro tr\u00ean l\u1ee3i nhu\u1eadn l\u00e0m c\u01a1 s\u1edf \u0111\u1ec3 quy\u1ebft \u0111\u1ecbnh \u0111\u1ea7u t\u01b0. Ch\u1eb3ng h\u1ea1n nh\u01b0, m\u1ed9t nh\u00e0 \u0111\u1ea7u t\u01b0 e ng\u1ea1i r\u1ee7i ro s\u1ebd l\u1ef1a ch\u1ecdn nh\u1eefng t\u00e0i s\u1ea3n c\u00f3 m\u1ee9c \u0111\u1ed9 dao \u0111\u1ed9ng th\u1ea5p v\u00e0 m\u1ee9c sinh l\u1eddi cao trong qu\u00e1 kh\u1ee9 khi so s\u00e1nh trong t\u01b0\u01a1ng quan v\u1edbi to\u00e0n th\u1ecb tr\u01b0\u1eddng. Tr\u00e1i l\u1ea1i, nh\u1eefng nh\u00e0 \u0111\u1ea7u t\u01b0 \u01b0a m\u1ea1o hi\u1ec3m th\u01b0\u1eddng t\u00ecm \u0111\u1ebfn nh\u1eefng t\u00e0i s\u1ea3n c\u00f3 m\u1ee9c \u0111\u1ed9 dao \u0111\u1ed9ng trong qu\u00e1 kh\u1ee9 cao \u0111\u1ec3 \u201cr\u00f3t v\u1ed1n\u201d.<\/p>\n<p>B\u00e0i h\u1ecdc r\u00fat ra ch\u00ednh khi \u0111\u1ea7u t\u01b0 v\u1edbi Coefficient of Variation<\/p>\n<p>\u2013\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 H\u1ec7 s\u1ed1 bi\u1ebfn thi\u00ean l\u00e0 m\u1ed9t th\u01b0\u1edbc \u0111o th\u1ed1ng k\u00ea v\u1ec1 m\u1ee9c \u0111\u1ed9 ph\u00e2n t\u00e1n t\u01b0\u01a1ng \u0111\u1ed1i c\u1ee7a c\u00e1c \u0111i\u1ec3m d\u1eef li\u1ec7u trong m\u1ed9t chu\u1ed7i d\u1eef li\u1ec7u xoay quanh gi\u00e1 tr\u1ecb trung b\u00ecnh.<\/p>\n<p>\u2013\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 Trong t\u00e0i ch\u00ednh, h\u1ec7 s\u1ed1 bi\u1ebfn thi\u00ean cho ph\u00e9p c\u00e1c nh\u00e0 \u0111\u1ea7u t\u01b0 d\u1ef1 \u0111o\u00e1n m\u1ee9c \u0111\u1ed9 bi\u1ebfn \u0111\u1ed9ng ho\u1eb7c r\u1ee7i ro \u0111\u01b0\u1ee3c gi\u1ea3 \u0111\u1ecbnh so v\u1edbi m\u1ee9c l\u1ee3i nhu\u1eadn k\u1ef3 v\u1ecdng t\u1eeb c\u00e1c kho\u1ea3n \u0111\u1ea7u t\u01b0.<\/p>\n<p>\u2013\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 T\u1ef7 l\u1ec7 gi\u1eefa \u0111\u1ed9 l\u1ec7ch chu\u1ea9n so v\u1edbi gi\u00e1 tr\u1ecb trung b\u00ecnh c\u00e0ng th\u1ea5p th\u00ec m\u1ee9c \u0111\u1ed9 r\u1ee7i ro c\u00e0ng h\u1ee3p l\u00fd.<\/p>\n<h2><span id=\"Cong_thuc_tinh_Coefficient_of_Variation_la_gi\"><strong>C\u00f4ng th\u1ee9c t\u00ednh Coefficient of Variation l\u00e0 g\u00ec?<\/strong><\/span><\/h2>\n<p>CV = \u0110\u1ed9 l\u1ec7ch chu\u1ea9n \/ Gi\u00e1 tr\u1ecb trung b\u00ecnh<\/p>\n<p>Hay: CV=<\/p>\n<p>Trong \u0111\u00f3: \u03c3 l\u00e0 \u0111\u1ed9 l\u1ec7ch chu\u1ea9n c\u1ee7a t\u1eadp h\u1ee3p d\u1eef li\u1ec7u<\/p>\n<p>\u03bc l\u00e0 gi\u00e1 tr\u1ecb trung b\u00ecnh c\u1ee7a t\u1eadp h\u1ee3p d\u1eef li\u1ec7u<\/p>\n<p>V\u00ed d\u1ee5 minh h\u1ecda t\u00ednh to\u00e1n v\u00e0 \u1ee9ng d\u1ee5ng Coefficient of Variation trong \u0111\u1ea7u t\u01b0<\/p>\n<p>V\u00ed d\u1ee5 1. T\u00ednh h\u1ec7 s\u1ed1 bi\u1ebfn thi\u00ean \u0111\u01a1n gi\u1ea3n th\u00f4ng qua l\u1ee3i nhu\u1eadn h\u00e0ng n\u0103m v\u00e0 \u0111\u1ed9 l\u1ec7ch chu\u1ea9n<\/p>\n<p>M\u1ed9t nh\u00e0 \u0111\u1ea7u t\u01b0 n\u1ecd e ng\u1ea1i r\u1ee7i ro, anh ta mong mu\u1ed1n t\u00ecm m\u1ed9t qu\u1ef9 \u0111\u1ea7u t\u01b0 c\u00f3 m\u1ee9c \u0111\u1ed9 dao \u0111\u1ed9ng trong qu\u00e1 kh\u1ee9 th\u1ea5p. Nh\u00e0 \u0111\u1ea7u t\u01b0 n\u00e0y ch\u1ecdn \u0111\u01b0\u1ee3c ba qu\u1ef9 \u0111\u1ea7u t\u01b0 A, B, C, sau \u0111\u00f3 ti\u1ebfn h\u00e0nh ph\u00e2n t\u00edch s\u1ed1 li\u1ec7u v\u1ec1 m\u1ee9c \u0111\u1ed9 dao \u0111\u1ed9ng v\u00e0 l\u1ee3i nhu\u1eadn c\u1ee7a ch\u00fang trong v\u00f2ng 15 n\u0103m qua. Th\u00f4ng tin ph\u00e2n t\u00edch th\u1ec3 hi\u1ec7n trong b\u1ea3ng d\u01b0\u1edbi \u0111\u00e2y:<\/p>\n<p>Qu\u1ef9 \u0111\u1ea7u t\u01b0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 \u0110\u1ed9 l\u1ec7ch chu\u1ea9n (\u03c3)\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 L\u1ee3i nhu\u1eadn h\u00e0ng n\u0103m (\u03bc)<\/p>\n<p>A\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 14,68%\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a05,47%<\/p>\n<p>B\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 21,31%\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 6,88%<\/p>\n<p>C\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 19,46%\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 7,16%<\/p>\n<p>Sau khi \u0111\u00e3 ho\u00e0n th\u00e0nh d\u1eef li\u1ec7u ph\u00e2n t\u00edch, nh\u00e0 \u0111\u1ea7u t\u01b0 n\u00e0y ti\u1ebfn h\u00e0nh t\u00ednh to\u00e1n h\u1ec7 s\u1ed1 bi\u1ebfn thi\u00ean v\u00e0 xem x\u00e9t nh\u01b0 sau:<\/p>\n<p>Qu\u1ef9 \u0111\u1ea7u t\u01b0\u00a0\u00a0\u00a0\u00a0<\/p>\n<p>A\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 CV = 14,68% \/ 5,47% = 2,68<\/p>\n<p>B\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 CV = 21,31% \/ 6,88% = 3,09<\/p>\n<p>\u00a0C\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 CV = 19,46% \/ 7,16% = 2,72<\/p>\n<p>D\u1ef1a v\u00e0o s\u1ed1 li\u1ec7u sau khi t\u00ednh to\u00e1n, th\u1ea5y r\u1eb1ng qu\u1ef9 A v\u00e0 C c\u00f3 h\u1ec7 s\u1ed1 bi\u1ebfn thi\u00ean th\u1ea5p h\u01a1n qu\u1ef9 B n\u00ean nh\u00e0 \u0111\u1ea7u t\u01b0 quy\u1ebft \u0111\u1ecbnh \u0111\u1ea7u t\u01b0 hai qu\u1ef9 n\u00e0y. L\u00fd do l\u00e0 v\u00ec t\u1ec9\u00a0l\u1ec7 r\u1ee7i ro tr\u00ean l\u1ee3i nhu\u1eadn c\u1ee7a hai qu\u1ef9 A v\u00e0 C kh\u00e1 gi\u1ed1ng nhau v\u00e0 t\u1ed1t h\u01a1n so v\u1edbi qu\u1ef9 B.<\/p>\n<p>V\u00ed d\u1ee5 2. T\u00ednh h\u1ec7 s\u1ed1 bi\u1ebfn thi\u00ean d\u1ef1a tr\u00ean x\u00e1c su\u1ea5t t\u1ef7 su\u1ea5t sinh l\u1eddi<\/p>\n<p>Hai qu\u1ef9 \u0111\u1ea7u t\u01b0 A v\u00e0 B c\u00f3 th\u00f4ng tin t\u00ecnh tr\u1ea1ng x\u00e1c su\u1ea5t t\u1ef7 su\u1ea5t sinh l\u1eddi nh\u01b0 trong b\u1ea3ng d\u01b0\u1edbi \u0111\u00e2y:<\/p>\n<p>Qu\u1ef9 \u0111\u1ea7u t\u01b0 A<\/p>\n<p>T\u00ecnh tr\u1ea1ng\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 X\u00e1c su\u1ea5t\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 T\u1ef7 su\u1ea5t sinh l\u1eddi<\/p>\n<p>X\u1ea5u nh\u1ea5t\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 20%\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 \u00a0\u00a0\u00a012%<\/p>\n<p>Trung b\u00ecnh\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 30%\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 13%<\/p>\n<p>T\u1ed1t nh\u1ea5t\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 50%\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 15%<\/p>\n<p>Qu\u1ef9 \u0111\u1ea7u t\u01b0 B<\/p>\n<p>X\u1ea5u nh\u1ea5t\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 10%\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 9%<\/p>\n<p>Trung b\u00ecnh\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 30%\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 12%<\/p>\n<p>T\u1ed1t nh\u1ea5t\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 60%\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 14%<\/p>\n<p>C\u0103n c\u1ee9 v\u00e0o s\u1ed1 li\u1ec7u n\u00e0y, nh\u00e0 \u0111\u1ea7u t\u01b0 ti\u1ebfn h\u00e0nh t\u00ednh to\u00e1n x\u00e1c \u0111\u1ecbnh h\u1ec7 s\u1ed1 bi\u1ebfn thi\u00ean c\u1ee7a t\u1eebng qu\u1ef9 \u0111\u1ea7u t\u01b0 v\u00e0 \u0111\u01b0a ra quy\u1ebft \u0111\u1ecbnh \u0111\u1ea7u t\u01b0. C\u00e1c b\u01b0\u1edbc l\u00e0m nh\u01b0 sau:<\/p>\n<p>B\u01b0\u1edbc 1. T\u00ednh h\u1ec7 s\u1ed1 bi\u1ebfn thi\u00ean c\u1ee7a qu\u1ef9 \u0111\u1ea7u t\u01b0 A<\/p>\n<p>\u2013 T\u1ef7 su\u1ea5t sinh l\u1eddi (qu\u1ef9 A): = 20% x 12% + 30% x 13% + 50% x 15% = 13,8%<\/p>\n<p>\u2013 \u0110\u1ed9 l\u1ec7ch chu\u1ea9n:<\/p>\n<p>\u00a0\u00a0\u00a0\u00a0 = 1,25%<\/p>\n<p>CVA = \u00a0= \u00a0= 0,09<\/p>\n<p>B\u01b0\u1edbc 2. T\u00ednh h\u1ec7 s\u1ed1 bi\u1ebfn thi\u00ean c\u1ee7a qu\u1ef9 \u0111\u1ea7u t\u01b0 B<\/p>\n<p>\u2013 T\u1ef7 su\u1ea5t sinh l\u1eddi (qu\u1ef9 B): TSSLB = 10% x 9% + 30% x 12% + 60% x 14% = 12,9%<\/p>\n<p>\u2013 \u0110\u1ed9 l\u1ec7ch chu\u1ea9n:<\/p>\n<p>\u00a0\u00a0\u00a0\u00a0 = 1,58%<\/p>\n<p>CVB = \u00a0= \u00a0= 0,12<\/p>\n<p>B\u01b0\u1edbc 3. Nh\u1eadn x\u00e9t<\/p>\n<p>So s\u00e1nh 2 qu\u1ef9 \u0111\u1ea7u t\u01b0 A v\u00e0 B, ta th\u1ea5y h\u1ec7 s\u1ed1 bi\u1ebfn thi\u00ean c\u1ee7a qu\u1ef9 \u0111\u1ea7u t\u01b0 B (CVB) l\u1edbn h\u01a1n so v\u1edbi qu\u1ef9 \u0111\u1ea7u t\u01b0 A (CVA). \u0110i\u1ec1u n\u00e0y \u0111\u1ed3ng ngh\u0129a \u0111\u1ea7u t\u01b0 v\u00e0o qu\u1ef9 A s\u1ebd ch\u1ecbu \u00edt r\u1ee7i ro h\u01a1n. Nh\u01b0 v\u1eady nh\u00e0 \u0111\u1ea7u t\u01b0 n\u00ean ch\u1ecdn qu\u1ef9 A.<\/p>\n<p>B\u00e0i vi\u1ebft n\u00e0y \u0111\u00e3 gi\u00fap b\u1ea1n \u0111\u1ecdc hi\u1ec3u r\u00f5 v\u1ec1 kh\u00e1i ni\u1ec7m Coefficient of Variation l\u00e0 g\u00ec c\u0169ng nh\u01b0 c\u00e1ch \u1ee9ng d\u1ee5ng t\u00ednh to\u00e1n v\u00e0 xem x\u00e9t trong \u0111\u1ea7u t\u01b0 t\u00e0i ch\u00ednh. Mong r\u1eb1ng s\u1ebd gi\u00fap b\u1ea1n \u0111\u1ecdc c\u00f3 \u0111\u01b0\u1ee3c nh\u1eefng th\u00f4ng tin v\u00e0 v\u00ed d\u1ee5 tham kh\u1ea3o h\u1eefu \u00edch. Ch\u00fac b\u1ea1n \u0111\u1ea7u t\u01b0 th\u00e0nh c\u00f4ng!<\/p>\n<p style=\"text-align: right\"><strong>Pha L\u00ea<\/strong><\/p>\n<p><!-- \/wp:paragraph --><\/p>\n<\/p><\/div>\n","protected":false},"excerpt":{"rendered":"<p>H\u1ec7 s\u1ed1 bi\u1ebfn thi\u00ean \u2013 <strong>Coefficient of Variation<\/strong> l\u00e0 g\u00ec? \u0110\u00e2y l\u00e0 m\u1ed9t th\u00f4ng s\u1ed1 quan tr\u1ecdng trong l\u0129nh v\u1ef1c to\u00e1n th\u1ed1ng k\u00ea. H\u1ec7 s\u1ed1 bi\u1ebfn thi\u00ean \u0111\u01b0\u1ee3c \u1ee9ng d\u1ee5ng \u1edf nhi\u1ec1u kh\u00eda c\u1ea1nh kh\u00e1c nhau c\u1ee7a cu\u1ed9c s\u1ed1ng, c\u1ea3 trong to\u00e1n h\u1ecdc, sinh h\u1ecdc, y d\u01b0\u1ee3c, t\u00e0i ch\u00ednh v\u00e0 \u0111\u1ea7u t\u01b0 ch\u1ee9ng kho\u00e1n\u2026 Th\u1ef1c ch\u1ea5t Coefficient of Variation l\u00e0 g\u00ec? \u01afu, nh\u01b0\u1ee3c \u0111i\u1ec3m l\u00e0 g\u00ec? C\u00e1ch \u1ee9ng d\u1ee5ng h\u1ec7 s\u1ed1 bi\u1ebfn thi\u00ean trong \u0111\u1ea7u t\u01b0 ra sao? D\u01b0\u1edbi \u0111\u00e2y l\u00e0 c\u00e2u tr\u1ea3 l\u1eddi d\u00e0nh cho b\u1ea1n.<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[429],"tags":[],"_links":{"self":[{"href":"https:\/\/masterskills.org\/blog\/wp-json\/wp\/v2\/posts\/21755"}],"collection":[{"href":"https:\/\/masterskills.org\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/masterskills.org\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/masterskills.org\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/masterskills.org\/blog\/wp-json\/wp\/v2\/comments?post=21755"}],"version-history":[{"count":0,"href":"https:\/\/masterskills.org\/blog\/wp-json\/wp\/v2\/posts\/21755\/revisions"}],"wp:attachment":[{"href":"https:\/\/masterskills.org\/blog\/wp-json\/wp\/v2\/media?parent=21755"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/masterskills.org\/blog\/wp-json\/wp\/v2\/categories?post=21755"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/masterskills.org\/blog\/wp-json\/wp\/v2\/tags?post=21755"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}