{"id":25193,"date":"2023-12-07T00:16:05","date_gmt":"2023-12-07T00:16:05","guid":{"rendered":"https:\/\/masterskills.org\/blog\/bac-tu-do-degrees-of-freedom-la-gi-cong-thuc-tinh-bac-tu-do.html"},"modified":"2023-12-22T10:08:48","modified_gmt":"2023-12-22T03:08:48","slug":"bac-tu-do-degrees-of-freedom-la-gi-cong-thuc-tinh-bac-tu-do","status":"publish","type":"post","link":"https:\/\/masterskills.org\/blog\/bac-tu-do-degrees-of-freedom-la-gi-cong-thuc-tinh-bac-tu-do.html","title":{"rendered":"B\u1eadc t\u1ef1 do (Degrees Of Freedom) l\u00e0 g\u00ec? C\u00f4ng th\u1ee9c t\u00ednh b\u1eadc t\u1ef1 do"},"content":{"rendered":"
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Hi\u0300nh minh ho\u0323a. Ngu\u00f4\u0300n: Daily-beat.com<\/i><\/p>\n<\/div>\n<\/div>\n

B\u1eadc t\u1ef1 do<\/font><\/h2>\n

Kha\u0301i ni\u00ea\u0323m<\/b><\/p>\n

B\u1eadc t\u1ef1 do<\/b> trong ti\u00ea\u0301ng Anh la\u0300 Degrees Of Freedom<\/b>.<\/p>\n

B\u1eadc t\u1ef1 do<\/b> \u0111\u1ec1 c\u1eadp \u0111\u1ebfn s\u1ed1 l\u01b0\u1ee3ng c\u00e1c gi\u00e1 tr\u1ecb \u0111\u1ed9c l\u1eadp t\u1ed1i \u0111a c\u1ee7a m\u1ed9t h\u1ec7, l\u00e0 c\u00e1c gi\u00e1 tr\u1ecb c\u00f3 th\u1ec3 thay \u0111\u1ed5i t\u1ef1 do trong m\u1eabu d\u1eef li\u1ec7u.\u00a0<\/p>\n

\u0110\u1ec3 hi\u1ec3u kh\u00e1i ni\u1ec7m B\u1eadc t\u1ef1 do \u0111\u01b0\u1ee3c t\u1ed1t nh\u1ea5t ch\u00fang ta s\u1eed d\u1ee5ng m\u1ed9t v\u00ed d\u1ee5: \u00a0 \u00a0\u00a0<\/p>\n

H\u00e3y xem x\u00e9t m\u1ed9t m\u1eabu d\u1eef li\u1ec7u \u0111\u01a1n gi\u1ea3n bao g\u1ed3m n\u0103m s\u1ed1 nguy\u00ean d\u01b0\u01a1ng. C\u00e1c gi\u00e1 tr\u1ecb c\u00f3 th\u1ec3 l\u00e0 b\u1ea5t k\u00ec s\u1ed1 n\u00e0o sao cho kh\u00f4ng c\u00f3 m\u1ed1i quan h\u1ec7 n\u00e0o gi\u1eefa ch\u00fang. V\u1ec1 m\u1eb7t l\u00ed thuy\u1ebft, m\u1eabu d\u1eef li\u1ec7u n\u00e0y s\u1ebd c\u00f3 n\u0103m b\u1eadc t\u1ef1 do.\u00a0<\/p>\n

Gi\u1ea3 s\u1eed bi\u1ebft b\u1ed1n s\u1ed1 trong m\u1eabu l\u00e0 {3, 8, 5, 4} v\u00e0 gi\u00e1 tr\u1ecb trung b\u00ecnh m\u1eabu d\u1eef li\u1ec7u l\u00e0 6.\u00a0<\/p>\n

\u0110i\u1ec1u n\u00e0y c\u00f3 ngh\u0129a l\u00e0 s\u1ed1 th\u1ee9 n\u0103m ph\u1ea3i b\u1eb1ng 10 m\u00e0 kh\u00f4ng th\u1ec3 l\u00e0 s\u1ed1 n\u00e0o kh\u00e1c, n\u00f3 \u0111\u01b0\u1ee3c g\u1ecdi l\u00e0 kh\u00f4ng th\u1ec3 t\u1ef1 do thay \u0111\u1ed5i. V\u00ec v\u1eady, b\u1eadc t\u1ef1 do cho m\u1eabu d\u1eef li\u1ec7u n\u00e0y l\u00e0 4.\u00a0<\/p>\n

C\u00f4ng th\u1ee9c t\u00ednh B\u1eadc t\u1ef1 do\u00a0<\/font><\/h3>\n

Df<\/sub> = N \u2013 1\u00a0<\/i><\/b><\/p>\n

Trong \u0111\u00f3:\u00a0<\/p>\n

– Df<\/sub> l\u00e0 b\u1eadc t\u1ef1 do\u00a0<\/p>\n

– N l\u00e0 k\u00edch th\u01b0\u1edbc m\u1eabu\u00a0<\/p>\n

B\u1eadc t\u1ef1 do th\u01b0\u1eddng \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng trong nhi\u1ec1u ph\u01b0\u01a1ng th\u1ee9c ki\u1ec3m \u0111\u1ecbnh gi\u1ea3 thuy\u1ebft trong th\u1ed1ng k\u00ea, ch\u1eb3ng h\u1ea1n nh\u01b0 ki\u1ec3m \u0111\u1ecbnh Chi b\u00ecnh ph\u01b0\u01a1ng (\u0111\u00f4i khi \u0111\u1ecdc l\u00e0 Khi b\u00ecnh ph\u01b0\u01a1ng).\u00a0<\/p>\n

Khi s\u1eed d\u1ee5ng ki\u1ec3m \u0111\u1ecbnh Chi b\u00ecnh ph\u01b0\u01a1ng v\u00e0 ki\u1ec3m tra t\u00ednh h\u1ee3p l\u1ec7 c\u1ee7a gi\u1ea3 thuy\u1ebft kh\u00f4ng, vi\u1ec7c t\u00ednh to\u00e1n b\u1eadc t\u1ef1 do l\u00e0 r\u1ea5t quan tr\u1ecdng. \u00a0\u00a0<\/i><\/p>\n

Ki\u1ec3m \u0111\u1ecbnh Chi b\u00ecnh ph\u01b0\u01a1ng\u00a0<\/font><\/h3>\n

C\u00f3 hai d\u1ea1ng ki\u1ec3m \u0111\u1ecbnh Chi b\u00ecnh ph\u01b0\u01a1ng l\u00e0:\u00a0<\/p>\n

– Ki\u1ec3m \u0111\u1ecbnh t\u00ednh \u0111\u1ed9c l\u1eadp \u0111\u1eb7t c\u00e2u h\u1ecfi v\u1ec1 c\u00e1c m\u1ed1i quan h\u1ec7 c\u1ee7a c\u00e1c bi\u1ebfn, ch\u1eb3ng h\u1ea1n nh\u01b0 “C\u00f3 m\u1ed1i quan h\u1ec7 n\u00e0o gi\u1eefa gi\u1edbi t\u00ednh th\u00ed sinh v\u00e0 \u0111i\u1ec3m to\u00e1n k\u00ec thi THPT kh\u00f4ng?”.\u00a0<\/p>\n

– Ki\u1ec3m \u0111\u1ecbnh m\u1ee9c \u0111\u1ed9 ph\u00f9 h\u1ee3p v\u1edbi c\u00e2u h\u1ecfi c\u00f3 d\u1ea1ng nh\u01b0 “N\u1ebfu m\u1ed9t \u0111\u1ed3ng xu \u0111\u01b0\u1ee3c tung 100 l\u1ea7n, li\u1ec7u m\u1eb7t ng\u1eeda s\u1ebd xu\u1ea5t hi\u1ec7n 50 l\u1ea7n v\u00e0 m\u1eb7t s\u1ea5p s\u1ebd xu\u1ea5t hi\u1ec7n 50 l\u1ea7n?”.\u00a0 \u00a0\u00a0<\/p>\n

\u0110\u1ed1i v\u1edbi c\u00e1c ki\u1ec3m \u0111\u1ecbnh n\u00e0y, b\u1eadc t\u1ef1 do<\/b> \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng \u0111\u1ec3 x\u00e1c \u0111\u1ecbnh li\u1ec7u c\u00f3 gi\u1ea3 thuy\u1ebft kh\u00f4ng n\u00e0o \u0111\u00f3 c\u00f3 th\u1ec3 b\u1ecb b\u00e1c b\u1ecf kh\u00f4ng d\u1ef1a tr\u00ean t\u1ed5ng s\u1ed1 bi\u1ebfn v\u00e0 c\u00e1c m\u1eabu trong ki\u1ec3m \u0111\u1ecbnh.\u00a0<\/p>\n

V\u00ed d\u1ee5, xem x\u00e9t vi\u1ec7c sinh vi\u00ean l\u1ef1a ch\u1ecdn kh\u00f3a h\u1ecdc, v\u1edbi 30 ho\u1eb7c 40 sinh vi\u00ean c\u1ee1 m\u1eabu c\u00f3 th\u1ec3 kh\u00f4ng \u0111\u1ee7 l\u1edbn \u0111\u1ec3 t\u1ea1o ra k\u1ebft qu\u1ea3 \u0111\u00e1ng tin c\u1eady. K\u1ebft qu\u1ea3 s\u1eed d\u1ee5ng c\u1ee1 m\u1eabu 400 ho\u1eb7c 500 sinh vi\u00ean s\u1ebd cho k\u1ebft qu\u1ea3 ch\u00ednh x\u00e1c h\u01a1n.\u00a0 \u00a0<\/p>\n

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

\n B\u1eadc t\u1ef1 do (ti\u1ebfng Anh: Degrees Of Freedom) l\u00e0 thu\u1eadt ng\u1eef s\u1eed d\u1ee5ng trong th\u1ed1ng k\u00ea ch\u1ec9 s\u1ed1 l\u01b0\u1ee3ng c\u00e1c gi\u00e1 tr\u1ecb c\u00f3 th\u1ec3 t\u1ef1 do thay \u0111\u1ed5i trong m\u1ed9t m\u1eabu d\u1eef li\u1ec7u.\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\/25193"}],"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=25193"}],"version-history":[{"count":0,"href":"https:\/\/masterskills.org\/blog\/wp-json\/wp\/v2\/posts\/25193\/revisions"}],"wp:attachment":[{"href":"https:\/\/masterskills.org\/blog\/wp-json\/wp\/v2\/media?parent=25193"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/masterskills.org\/blog\/wp-json\/wp\/v2\/categories?post=25193"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/masterskills.org\/blog\/wp-json\/wp\/v2\/tags?post=25193"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}