{"id":25876,"date":"2023-12-07T02:13:53","date_gmt":"2023-12-07T02:13:53","guid":{"rendered":"https:\/\/masterskills.org\/blog\/he-so-bien-thien-coefficient-of-variation-cv-la-gi-nhung-dac-diem-can-luu-y.html"},"modified":"2023-12-22T11:22:11","modified_gmt":"2023-12-22T04:22:11","slug":"he-so-bien-thien-coefficient-of-variation-cv-la-gi-nhung-dac-diem-can-luu-y","status":"publish","type":"post","link":"https:\/\/masterskills.org\/blog\/he-so-bien-thien-coefficient-of-variation-cv-la-gi-nhung-dac-diem-can-luu-y.html","title":{"rendered":"H\u1ec7 s\u1ed1 bi\u1ebfn thi\u00ean (Coefficient of Variation \u2013 CV) l\u00e0 g\u00ec? Nh\u1eefng \u0111\u1eb7c \u0111i\u1ec3m c\u1ea7n l\u01b0u \u00fd"},"content":{"rendered":"
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H\u00ecnh minh h\u1ecda. Ngu\u1ed3n: Digitalvidya.com<\/p>\n<\/div>\n<\/div>\n

H\u1ec7 s\u1ed1 bi\u1ebfn thi\u00ean<\/font><\/h2>\n

Kh\u00e1i ni\u1ec7m<\/b><\/p>\n

H\u1ec7 s\u1ed1 bi\u1ebfn thi\u00ean<\/b>, ti\u1ebfng Anh g\u1ecdi l\u00e0 coefficient of variation<\/b>, vi\u1ebft t\u1eaft l\u00e0 CV<\/b>.<\/p>\n

H\u1ec7 s\u1ed1 bi\u1ebfn thi\u00ean<\/b> l\u00e0 m\u1ed9t th\u01b0\u1edbc \u0111o th\u1ed1ng k\u00ea \u0111\u1ed9 ph\u00e2n t\u00e1n c\u1ee7a c\u00e1c d\u1eef li\u1ec7u trong m\u1ed9t chu\u1ed7i d\u1eef li\u1ec7u so v\u1edbi gi\u00e1 tr\u1ecb trung b\u00ecnh.<\/p>\n

H\u1ec7 s\u1ed1 bi\u1ebfn thi\u00ean <\/b>l\u00e0 t\u1ec9 l\u1ec7 c\u1ee7a\u00a0\u0111\u1ed9 l\u1ec7ch chu\u1ea9n\u00a0(standard deviation)\u00a0so v\u1edbi\u00a0gi\u00e1 tr\u1ecb trung b\u00ecnh\u00a0(mean). N\u00f3 l\u00e0 m\u1ed9t 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, cho d\u00f9 gi\u00e1 tr\u1ecb trung b\u00ecnh c\u1ee7a ch\u00fang r\u1ea5t kh\u00e1c nhau.<\/p>\n

Hi\u1ec3u r\u00f5 h\u01a1n v\u1ec1 h\u1ec7 s\u1ed1 bi\u1ebfn thi\u00ean<\/font><\/h3>\n

H\u1ec7 s\u1ed1 bi\u1ebfn thi\u00ean<\/b> cho th\u1ea5y m\u1ee9c \u0111\u1ed9 bi\u1ebfn thi\u00ean c\u1ee7a d\u1eef li\u1ec7u trong m\u1ed9t m\u1eabu t\u01b0\u01a1ng quan v\u1edbi gi\u00e1 tr\u1ecb trung b\u00ecnh c\u1ee7a t\u1ed5ng th\u1ec3. Trong t\u00e0i ch\u00ednh, h\u1ec7 s\u1ed1 bi\u1ebfn thi\u00ean gi\u00fap nh\u00e0 \u0111\u1ea7u t\u01b0 x\u00e1c \u0111\u1ecbnh \u0111\u01b0\u1ee3c m\u1ee9c \u0111\u1ed9 dao \u0111\u1ed9ng hay r\u1ee7i ro ph\u1ea3i ch\u1ecbu \u0111\u1ec3 c\u00f3 l\u1ee3i nhu\u1eadn k\u00ec v\u1ecdng c\u1ee7a kho\u1ea3n \u0111\u1ea7u t\u01b0.<\/p>\n

Tr\u01b0\u1eddng h\u1ee3p l\u00ed t\u01b0\u1edfng nh\u1ea5t l\u00e0 khi h\u1ec7 s\u1ed1 bi\u1ebfn thi\u00ean, hay t\u1ec9 l\u1ec7 c\u1ee7a \u0111\u1ed9 l\u1ec7ch chu\u1ea9n so v\u1edbi gi\u00e1 tr\u1ecb trung b\u00ecnh, th\u1ea5p. Vi\u1ec7c n\u00e0y c\u00f3 ngh\u0129a l\u00e0 t\u1ec9 l\u1ec7 r\u1ee7i ro tr\u00ean l\u1ee3i nhu\u1eadn h\u1ee3p l\u00ed. L\u01b0u \u00fd l\u00e0 n\u1ebfu l\u1ee3i nhu\u1eadn k\u00ec v\u1ecdng n\u1eb1m \u1edf m\u1eabu s\u1ed1 b\u1eb1ng 0 ho\u1eb7c \u00e2m th\u00ec h\u1ec7 s\u1ed1 bi\u1ebfn thi\u00ean c\u00f3 th\u1ec3 s\u1ebd sai.<\/p>\n

H\u1ec7 s\u1ed1 bi\u1ebfn thi\u00ean<\/b> s\u1ebd h\u1eefu \u00edch khi 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. V\u00ed d\u1ee5, m\u1ed9t nh\u00e0 \u0111\u1ea7u t\u01b0 ng\u1ea1i r\u1ee7i ro s\u1ebd xem x\u00e9t nh\u1eefng t\u00e0i s\u1ea3n c\u00f3 \u0111\u1ed9 dao \u0111\u1ed9ng trong qu\u00e1 kh\u1ee9 th\u1ea5p v\u00e0 m\u1ee9c sinh l\u1eddi cao khi so t\u01b0\u01a1ng quan v\u1edbi to\u00e0n th\u1ecb tr\u01b0\u1eddng hay ng\u00e0nh c\u1ee7a n\u00f3. Ng\u01b0\u1ee3c l\u1ea1i, nh\u1eefng nh\u00e0 \u0111\u1ea7u t\u01b0 \u01b0a m\u1ea1o hi\u1ec3m th\u01b0\u1eddng t\u00ecm c\u01a1 h\u1ed9i \u0111\u1ea7u t\u01b0 v\u00e0o nh\u1eefng t\u00e0i s\u1ea3n c\u00f3 \u0111\u1ed9 dao \u0111\u1ed9ng trong qu\u00e1 kh\u1ee9 cao.<\/p>\n

C\u00f4ng th\u1ee9c c\u1ee7a h\u1ec7 s\u1ed1 bi\u1ebfn thi\u00ean<\/font><\/h3>\n

H\u1ec7 s\u1ed1 bi\u1ebfn thi\u00ean = \u0110\u1ed9 l\u1ec7ch chu\u1ea9n \/ Gi\u00e1 tr\u1ecb trung b\u00ecnh<\/b><\/p>\n

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V\u00ed d\u1ee5 v\u1ec1 vi\u1ec7c s\u1eed d\u1ee5ng h\u1ec7 s\u1ed1 bi\u1ebfn thi\u00ean khi quy\u1ebft \u0111\u1ecbnh \u0111\u1ea7u t\u01b0<\/font><\/h3>\n

M\u1ed9t nh\u00e0 \u0111\u1ea7u t\u01b0 ng\u1ea1i r\u1ee7i ro mong mu\u1ed1n \u0111\u1ea7u t\u01b0 v\u00e0o m\u1ed9t qu\u0129 \u0111\u1ea7u t\u01b0. Anh \u1ea5y ch\u1ecdn \u0111\u01b0\u1ee3c ba qu\u0129 \u0111\u1ea7u t\u01b0 A, B, C. Sau \u0111\u00f3 anh \u1ea5y ph\u00e2n t\u00edch s\u1ed1 li\u1ec7u v\u1ec1 l\u1ee3i nhu\u1eadn v\u00e0 \u0111\u1ed9 dao \u0111\u1ed9ng c\u1ee7a c\u00e1c qu\u0129 n\u00e0y trong v\u00f2ng 15 n\u0103m qua. Anh \u1ea5y cho r\u1eb1ng trong t\u01b0\u01a1ng lai d\u00e0i h\u1ea1n, nh\u1eefng qu\u0129 n\u00e0y s\u1ebd \u0111em l\u1ea1i k\u1ebft qu\u1ea3 t\u01b0\u01a1ng t\u1ef1 nh\u01b0 v\u1eady. Th\u00f4ng tin anh \u1ea5y ph\u00e2n t\u00edch \u0111\u01b0\u1ee3c t\u1eeb ba qu\u0129 n\u00e0y l\u00e0:<\/p>\n

– Qu\u0129 A c\u00f3 l\u1ee3i nhu\u1eadn h\u00e0ng n\u0103m l\u00e0 5,47% v\u00e0 \u0111\u1ed9 l\u1ec7ch chu\u1ea9n l\u00e0 14,68%. H\u1ec7 s\u1ed1 bi\u1ebfn thi\u00ean<\/b> c\u1ee7a qu\u0129 A l\u00e0 2,68.<\/p>\n

– Qu\u0129 B c\u00f3 l\u1ee3i nhu\u1eadn h\u00e0ng n\u0103m l\u00e0 6,88% v\u00e0 \u0111\u1ed9 l\u1ec7ch chu\u1ea9n l\u00e0 21,31%. H\u1ec7 s\u1ed1 bi\u1ebfn thi\u00ean <\/b>c\u1ee7a qu\u0129 B l\u00e0 3,09.<\/p>\n

– Qu\u0129 C c\u00f3 l\u1ee3i nhu\u1eadn h\u00e0ng n\u0103m l\u00e0 7,16% v\u00e0 \u0111\u1ed9 l\u1ec7ch chu\u1ea9n l\u00e0 19,46%. H\u1ec7 s\u1ed1 bi\u1ebfn thi\u00ean<\/b> c\u1ee7a qu\u0129 C l\u00e0 2,72.<\/p>\n

D\u1ef1a v\u00e0o s\u1ed1 li\u1ec7u tr\u00ean, nh\u00e0 \u0111\u1ea7u t\u01b0 n\u00e0y quy\u1ebft \u0111\u1ecbnh \u0111\u1ea7u t\u01b0 v\u00e0o qu\u0129 A ho\u1eb7c qu\u0129 C v\u00ec t\u1ec9\u00a0l\u1ec7 r\u1ee7i ro tr\u00ean l\u1ee3i nhu\u1eadn kh\u00e1 gi\u1ed1ng nhau v\u00e0 t\u1ed1t h\u01a1n so v\u1edbi qu\u0129 B.<\/p>\n

(Theo Investopedia<\/i>)<\/p>\n<\/p><\/div>\n","protected":false},"excerpt":{"rendered":"

\n H\u1ec7 s\u1ed1 bi\u1ebfn thi\u00ean (ti\u1ebfng Anh: Coefficient of variation, vi\u1ebft t\u1eaft: CV) l\u00e0 m\u1ed9t th\u01b0\u1edbc \u0111o th\u1ed1ng k\u00ea \u0111\u1ed9 ph\u00e2n t\u00e1n c\u1ee7a c\u00e1c d\u1eef li\u1ec7u trong m\u1ed9t chu\u1ed7i d\u1eef li\u1ec7u so v\u1edbi gi\u00e1 tr\u1ecb trung b\u00ecnh.\n <\/div>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[414],"tags":[],"_links":{"self":[{"href":"https:\/\/masterskills.org\/blog\/wp-json\/wp\/v2\/posts\/25876"}],"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=25876"}],"version-history":[{"count":0,"href":"https:\/\/masterskills.org\/blog\/wp-json\/wp\/v2\/posts\/25876\/revisions"}],"wp:attachment":[{"href":"https:\/\/masterskills.org\/blog\/wp-json\/wp\/v2\/media?parent=25876"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/masterskills.org\/blog\/wp-json\/wp\/v2\/categories?post=25876"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/masterskills.org\/blog\/wp-json\/wp\/v2\/tags?post=25876"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}