{"id":77005,"date":"2022-08-13T19:47:10","date_gmt":"2022-08-13T12:47:10","guid":{"rendered":"http:\/\/httl.com.vn\/wiki\/cross-validation-la-gi\/"},"modified":"2022-08-13T19:47:10","modified_gmt":"2022-08-13T12:47:10","slug":"cross-validation-la-gi","status":"publish","type":"post","link":"https:\/\/httl.com.vn\/wiki\/cross-validation-la-gi\/","title":{"rendered":"Gi\u1edbi thi\u1ec7u v\u1ec1 k-fold cross-validation – Tr\u00ed tu\u1ec7 nh\u00e2n t\u1ea1o"},"content":{"rendered":"

x\u00e1c th\u1ef1c ch\u00e9o l\u00e0 m\u1ed9t ph\u01b0\u01a1ng ph\u00e1p th\u1ed1ng k\u00ea \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng \u0111\u1ec3 \u01b0\u1edbc t\u00ednh hi\u1ec7u su\u1ea5t c\u1ee7a c\u00e1c m\u00f4 h\u00ecnh h\u1ecdc m\u00e1y. n\u00f3 th\u01b0\u1eddng \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng \u0111\u1ec3 so s\u00e1nh v\u00e0 l\u1ef1a ch\u1ecdn m\u00f4 h\u00ecnh t\u1ed1t nh\u1ea5t cho m\u1ed9t v\u1ea5n \u0111\u1ec1. k\u1ef9 thu\u1eadt n\u00e0y d\u1ec5 hi\u1ec3u, d\u1ec5 th\u1ef1c hi\u1ec7n v\u00e0 cung c\u1ea5p c\u00e1c \u01b0\u1edbc t\u00ednh \u0111\u00e1ng tin c\u1eady h\u01a1n c\u00e1c ph\u01b0\u01a1ng ph\u00e1p kh\u00e1c. Trong b\u00e0i vi\u1ebft n\u00e0y, ch\u00fang ta s\u1ebd c\u00f9ng trituenhantao.io t\u00ecm hi\u1ec3u v\u1ec1 k\u1ef9 thu\u1eadt x\u00e1c th\u1ef1c ch\u00e9o k-l\u1ea7n. <\/p>\n

x\u00e1c th\u1ef1c ch\u00e9o <\/p>\n

k-fold l\u00e0 g\u00ec? <\/h2>\n

X\u00e1c th\u1ef1c ch\u00e9o l\u00e0 m\u1ed9t k\u1ef9 thu\u1eadt l\u1ea5y m\u1eabu \u0111\u1ec3 \u0111\u00e1nh gi\u00e1 m\u00f4 h\u00ecnh h\u1ecdc m\u00e1y trong tr\u01b0\u1eddng h\u1ee3p d\u1eef li\u1ec7u kh\u00f4ng nhi\u1ec1u. <\/p>\n

Tham s\u1ed1 ch\u00ednh trong k\u1ef9 thu\u1eadt n\u00e0y l\u00e0 k, \u0111\u1ea1i di\u1ec7n cho s\u1ed1 l\u01b0\u1ee3ng nh\u00f3m m\u00e0 d\u1eef li\u1ec7u s\u1ebd \u0111\u01b0\u1ee3c chia. v\u00ec l\u00fd do \u0111\u00f3, n\u00f3 \u0111\u01b0\u1ee3c g\u1ecdi l\u00e0 x\u00e1c nh\u1eadn ch\u00e9o k-l\u1ea7n. khi gi\u00e1 tr\u1ecb c\u1ee7a k \u0111\u01b0\u1ee3c ch\u1ecdn, gi\u00e1 tr\u1ecb \u0111\u00f3 \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng tr\u1ef1c ti\u1ebfp trong t\u00ean c\u1ee7a ph\u01b0\u01a1ng ph\u00e1p \u0111\u00e1nh gi\u00e1. v\u00ed d\u1ee5: v\u1edbi k = 10, ph\u01b0\u01a1ng ph\u00e1p s\u1ebd \u0111\u01b0\u1ee3c g\u1ecdi l\u00e0 x\u00e1c th\u1ef1c ch\u00e9o 10 l\u1ea7n. <\/strong> <\/p>\n

K\u1ef9 thu\u1eadt n\u00e0y th\u01b0\u1eddng bao g\u1ed3m c\u00e1c b\u01b0\u1edbc sau: <\/p>\n

    \n
  1. x\u00e1o tr\u1ed9n t\u1eadp d\u1eef li\u1ec7u m\u1ed9t c\u00e1ch ng\u1eabu nhi\u00ean <\/li>\n
  2. chia t\u1eadp d\u1eef li\u1ec7u th\u00e0nh k nh\u00f3m <\/li>\n
  3. cho m\u1ed7i nh\u00f3m:\n
      \n
    1. s\u1eed d\u1ee5ng nh\u00f3m hi\u1ec7n t\u1ea1i \u0111\u1ec3 \u0111\u00e1nh gi\u00e1 hi\u1ec7u qu\u1ea3 c\u1ee7a m\u00f4 h\u00ecnh <\/li>\n
    2. c\u00e1c nh\u00f3m c\u00f2n l\u1ea1i \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng \u0111\u1ec3 \u0111\u00e0o t\u1ea1o m\u00f4 h\u00ecnh <\/li>\n
    3. \u0111\u00e0o t\u1ea1o m\u00f4 h\u00ecnh <\/li>\n
    4. \u0111\u00e1nh gi\u00e1 v\u00e0 sau \u0111\u00f3 ph\u00e1 h\u1ee7y m\u00f4 h\u00ecnh <\/li>\n<\/ol>\n

      m\u1ed9t l\u01b0u \u00fd quan tr\u1ecdng l\u00e0 m\u1ed7i m\u1eabu \u0111\u01b0\u1ee3c ch\u1ec9 \u0111\u1ecbnh cho m\u1ed9t nh\u00f3m duy nh\u1ea5t v\u00e0 ph\u1ea3i \u1edf trong nh\u00f3m \u0111\u00f3 trong su\u1ed1t ph\u1ea7n c\u00f2n l\u1ea1i c\u1ee7a qu\u00e1 tr\u00ecnh. vi\u1ec7c x\u1eed l\u00fd tr\u01b0\u1edbc d\u1eef li\u1ec7u, ch\u1eb3ng h\u1ea1n nh\u01b0 x\u00e2y d\u1ef1ng t\u1eeb v\u1ef1ng, ch\u1ec9 \u0111\u01b0\u1ee3c th\u1ef1c hi\u1ec7n tr\u00ean t\u1eadp hu\u1ea5n luy\u1ec7n ph\u00e2n t\u00e1ch, kh\u00f4ng ph\u1ea3i tr\u00ean t\u1eadp d\u1eef li\u1ec7u \u0111\u1ea7y \u0111\u1ee7. Y\u00eau c\u1ea7u ph\u00e1 h\u1ee7y m\u00f4 h\u00ecnh sau m\u1ed7i l\u1ea7n \u0111\u00e1nh gi\u00e1, ng\u0103n m\u00f4 h\u00ecnh nh\u1edb nh\u00e3n c\u1ee7a b\u1ed9 th\u1eed nghi\u1ec7m trong l\u1ea7n \u0111\u00e1nh gi\u00e1 tr\u01b0\u1edbc. nh\u1eefng l\u1ed7i c\u1ea5u h\u00ecnh n\u00e0y r\u1ea5t d\u1ec5 m\u1eafc ph\u1ea3i v\u00e0 t\u1ea5t c\u1ea3 \u0111\u1ec1u d\u1eabn \u0111\u1ebfn k\u1ebft qu\u1ea3 \u0111\u00e1nh gi\u00e1 kh\u00f4ng ch\u00ednh x\u00e1c (th\u01b0\u1eddng t\u00edch c\u1ef1c h\u01a1n k\u1ebft qu\u1ea3 th\u1ef1c). <\/p>\n

      k\u1ebft qu\u1ea3 t\u1ed5ng h\u1ee3p th\u01b0\u1eddng l\u00e0 gi\u00e1 tr\u1ecb trung b\u00ecnh c\u1ee7a c\u00e1c \u0111\u00e1nh gi\u00e1. Ngo\u00e0i ra, tr\u00ean th\u1ef1c t\u1ebf, vi\u1ec7c b\u1ed5 sung th\u00f4ng tin ph\u01b0\u01a1ng sai v\u00e0 \u0111\u1ed9 l\u1ec7ch chu\u1ea9n v\u00e0o c\u00e1c k\u1ebft qu\u1ea3 t\u1ed5ng h\u1ee3p c\u0169ng \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng. <\/p>\n

      c\u00e0i \u0111\u1eb7t <\/h2>\n

      gi\u00e1 tr\u1ecb k l\u00e0 m\u1ed9t tham s\u1ed1 quan tr\u1ecdng \u0111\u1ec3 \u0111\u00e1nh gi\u00e1 ch\u00ednh x\u00e1c m\u00f4 h\u00ecnh, v\u1eady l\u00e0m c\u00e1ch n\u00e0o \u0111\u1ec3 ch\u1ecdn tham s\u1ed1 n\u00e0y? <\/p>\n

      ba chi\u1ebfn l\u01b0\u1ee3c ph\u1ed5 bi\u1ebfn \u0111\u1ec3 ch\u1ecdn k: <\/p>\n

        \n
      • \u0111\u1ea1i di\u1ec7n <\/strong>: Gi\u00e1 tr\u1ecb c\u1ee7a k \u0111\u01b0\u1ee3c ch\u1ecdn sao cho m\u1ed7i t\u1eadp ki\u1ec3m tra \/ hu\u1ea5n luy\u1ec7n \u0111\u1ee7 l\u1edbn \u0111\u1ec3 \u0111\u1ea1i di\u1ec7n v\u1ec1 m\u1eb7t th\u1ed1ng k\u00ea cho t\u1eadp d\u1eef li\u1ec7u ch\u1ee9a n\u00f3. <\/li>\n
      • k = 10 <\/strong>: Gi\u00e1 tr\u1ecb c\u1ee7a k \u0111\u01b0\u1ee3c \u0111\u1eb7t th\u00e0nh 10, m\u1ed9t gi\u00e1 tr\u1ecb \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng ph\u1ed5 bi\u1ebfn v\u00e0 \u0111\u00e3 \u0111\u01b0\u1ee3c ch\u1ee9ng minh l\u00e0 t\u1ea1o ra sai s\u1ed1 nh\u1ecf, ph\u01b0\u01a1ng sai th\u1ea5p (th\u00f4ng qua th\u1eed nghi\u1ec7m). <\/li>\n
      • k = n <\/strong>: gi\u00e1 tr\u1ecb c\u1ee7a k \u0111\u01b0\u1ee3c \u0111\u1eb7t th\u00e0nh n, trong \u0111\u00f3 n l\u00e0 k\u00edch th\u01b0\u1edbc c\u1ee7a t\u1eadp d\u1eef li\u1ec7u, v\u00ec v\u1eady m\u1ed7i m\u1eabu s\u1ebd \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng \u0111\u1ec3 \u0111\u00e1nh gi\u00e1 m\u00f4 h\u00ecnh m\u1ed9t l\u1ea7n. ph\u01b0\u01a1ng ph\u00e1p n\u00e0y c\u00f2n \u0111\u01b0\u1ee3c g\u1ecdi l\u00e0 x\u00e1c th\u1ef1c ch\u00e9o \u0111\u1ec3 l\u1ea1i m\u1ed9t ph\u01b0\u01a1ng ph\u00e1p. <\/li>\n<\/ul>\n

        gi\u00e1 tr\u1ecb k = 10 l\u00e0 m\u1ed9t c\u1ea5u h\u00ecnh r\u1ea5t ph\u1ed5 bi\u1ebfn. b\u1ea1n n\u00ean s\u1eed d\u1ee5ng gi\u00e1 tr\u1ecb n\u00e0y n\u1ebfu b\u1ea1n g\u1eb7p kh\u00f3 kh\u0103n khi ch\u1ecdn m\u1ed9t gi\u00e1 tr\u1ecb th\u00edch h\u1ee3p cho v\u1ea5n \u0111\u1ec1 c\u1ee7a m\u00ecnh. Ngo\u00e0i ra, b\u1ea1n c\u0169ng ph\u1ea3i ch\u1ecdn m\u1ed9t gi\u00e1 tr\u1ecb c\u1ee7a k \u0111\u1ec3 c\u00e1c m\u1eabu c\u00f3 th\u1ec3 \u0111\u01b0\u1ee3c chia \u0111\u1ec1u th\u00e0nh c\u00e1c nh\u00f3m. th\u01b0 vi\u1ec7n scikit-learning cung c\u1ea5p tri\u1ec3n khai x\u00e1c th\u1ef1c ch\u00e9o ho\u00e0n ch\u1ec9nh. b\u1ea1n c\u00f3 th\u1ec3 ki\u1ec3m tra api l\u1ef1a ch\u1ecdn m\u00f4 h\u00ecnh. <\/p>\n

        N\u1ebfu b\u1ea1n th\u1ea5y b\u00e0i vi\u1ebft h\u1eefu \u00edch, \u0111\u1eebng ng\u1ea1i chia s\u1ebb cho nh\u1eefng ai quan t\u00e2m. H\u00e3y th\u01b0\u1eddng xuy\u00ean gh\u00e9 th\u0103m trituenhantao.io ho\u1eb7c subscribe (d\u01b0\u1edbi ch\u00e2n trang) \u0111\u1ec3 nh\u1eadn nh\u1eefng b\u00e0i vi\u1ebft t\u01b0\u01a1ng t\u1ef1 trong th\u1eddi gian s\u1edbm nh\u1ea5t! <\/p>\n","protected":false},"excerpt":{"rendered":"

        x\u00e1c th\u1ef1c ch\u00e9o l\u00e0 m\u1ed9t ph\u01b0\u01a1ng ph\u00e1p th\u1ed1ng k\u00ea \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng \u0111\u1ec3 \u01b0\u1edbc t\u00ednh hi\u1ec7u su\u1ea5t c\u1ee7a c\u00e1c m\u00f4 h\u00ecnh h\u1ecdc m\u00e1y. n\u00f3 th\u01b0\u1eddng \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng \u0111\u1ec3 so s\u00e1nh v\u00e0 l\u1ef1a ch\u1ecdn m\u00f4 h\u00ecnh t\u1ed1t nh\u1ea5t cho m\u1ed9t v\u1ea5n \u0111\u1ec1. k\u1ef9 thu\u1eadt n\u00e0y d\u1ec5 hi\u1ec3u, d\u1ec5 th\u1ef1c hi\u1ec7n v\u00e0 cung c\u1ea5p c\u00e1c \u01b0\u1edbc…<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[44],"tags":[],"_links":{"self":[{"href":"https:\/\/httl.com.vn\/wiki\/wp-json\/wp\/v2\/posts\/77005"}],"collection":[{"href":"https:\/\/httl.com.vn\/wiki\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/httl.com.vn\/wiki\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/httl.com.vn\/wiki\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/httl.com.vn\/wiki\/wp-json\/wp\/v2\/comments?post=77005"}],"version-history":[{"count":0,"href":"https:\/\/httl.com.vn\/wiki\/wp-json\/wp\/v2\/posts\/77005\/revisions"}],"wp:attachment":[{"href":"https:\/\/httl.com.vn\/wiki\/wp-json\/wp\/v2\/media?parent=77005"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/httl.com.vn\/wiki\/wp-json\/wp\/v2\/categories?post=77005"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/httl.com.vn\/wiki\/wp-json\/wp\/v2\/tags?post=77005"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}