{"id":476644,"date":"2023-08-09T07:31:20","date_gmt":"2023-08-09T07:31:20","guid":{"rendered":""},"modified":"2023-09-05T11:13:10","modified_gmt":"2023-09-05T11:13:10","slug":"data-imputation","status":"publish","type":"wiki","link":"https:\/\/oneproxy.pro\/vn\/wiki\/data-imputation\/","title":{"rendered":"D\u1eef li\u1ec7u b\u1ecb c\u1eaft b\u1ecf"},"content":{"rendered":"<h2>Gi\u1edbi thi\u1ec7u<\/h2>\n<p>Vi\u1ec7c x\u1eed l\u00fd d\u1eef li\u1ec7u l\u00e0 m\u1ed9t k\u1ef9 thu\u1eadt quan tr\u1ecdng trong l\u0129nh v\u1ef1c ph\u00e2n t\u00edch d\u1eef li\u1ec7u v\u00e0 x\u1eed l\u00fd d\u1eef li\u1ec7u. N\u00f3 li\u00ean quan \u0111\u1ebfn qu\u00e1 tr\u00ecnh \u0111i\u1ec1n v\u00e0o c\u00e1c \u0111i\u1ec3m d\u1eef li\u1ec7u b\u1ecb thi\u1ebfu ho\u1eb7c kh\u00f4ng \u0111\u1ea7y \u0111\u1ee7 trong t\u1eadp d\u1eef li\u1ec7u v\u1edbi c\u00e1c gi\u00e1 tr\u1ecb \u01b0\u1edbc t\u00ednh. Ph\u01b0\u01a1ng ph\u00e1p n\u00e0y \u0111\u00f3ng m\u1ed9t vai tr\u00f2 quan tr\u1ecdng trong vi\u1ec7c n\u00e2ng cao ch\u1ea5t l\u01b0\u1ee3ng d\u1eef li\u1ec7u, cho ph\u00e9p ph\u00e2n t\u00edch, m\u00f4 h\u00ecnh h\u00f3a v\u00e0 ra quy\u1ebft \u0111\u1ecbnh ch\u00ednh x\u00e1c v\u00e0 \u0111\u00e1ng tin c\u1eady h\u01a1n.<\/p>\n<h2>L\u1ecbch s\u1eed v\u00e0 ngu\u1ed3n g\u1ed1c<\/h2>\n<p>Kh\u00e1i ni\u1ec7m v\u1ec1 vi\u1ec7c quy n\u1ea1p d\u1eef li\u1ec7u \u0111\u00e3 t\u1ed3n t\u1ea1i trong nhi\u1ec1u th\u1ebf k\u1ef7, v\u1edbi nhi\u1ec1u n\u1ed7 l\u1ef1c ban \u0111\u1ea7u nh\u1eb1m \u01b0\u1edbc t\u00ednh c\u00e1c gi\u00e1 tr\u1ecb c\u00f2n thi\u1ebfu trong c\u00e1c t\u1eadp d\u1eef li\u1ec7u. Tuy nhi\u00ean, n\u00f3 tr\u1edf n\u00ean n\u1ed5i b\u1eadt h\u01a1n v\u1edbi s\u1ef1 ra \u0111\u1eddi c\u1ee7a m\u00e1y t\u00ednh v\u00e0 ph\u00e2n t\u00edch th\u1ed1ng k\u00ea trong th\u1ebf k\u1ef7 20. Vi\u1ec7c \u0111\u1ec1 c\u1eadp \u0111\u1ebfn l\u1ea7n \u0111\u1ea7u ti\u00ean v\u1ec1 vi\u1ec7c c\u1eaft b\u1ecf d\u1eef li\u1ec7u c\u00f3 th\u1ec3 b\u1eaft ngu\u1ed3n t\u1eeb t\u00e1c ph\u1ea9m c\u1ee7a Donald B. Rubin, ng\u01b0\u1eddi \u0111\u00e3 gi\u1edbi thi\u1ec7u nhi\u1ec1u k\u1ef9 thu\u1eadt c\u1eaft b\u1ecf d\u1eef li\u1ec7u v\u00e0o nh\u1eefng n\u0103m 1970.<\/p>\n<h2>Th\u00f4ng tin chi ti\u1ebft<\/h2>\n<p>Vi\u1ec7c quy n\u1ea1p d\u1eef li\u1ec7u l\u00e0 m\u1ed9t ph\u01b0\u01a1ng ph\u00e1p th\u1ed1ng k\u00ea t\u1eadn d\u1ee5ng th\u00f4ng tin c\u00f3 s\u1eb5n trong t\u1eadp d\u1eef li\u1ec7u \u0111\u1ec3 \u0111\u01b0a ra nh\u1eefng ph\u1ecfng \u0111o\u00e1n c\u00f3 c\u0103n c\u1ee9 v\u1ec1 c\u00e1c gi\u00e1 tr\u1ecb c\u00f2n thi\u1ebfu. N\u00f3 gi\u00fap gi\u1ea3m thi\u1ec3u sai l\u1ec7ch v\u00e0 bi\u1ebfn d\u1ea1ng c\u00f3 th\u1ec3 ph\u00e1t sinh do d\u1eef li\u1ec7u kh\u00f4ng \u0111\u1ea7y \u0111\u1ee7, \u0111i\u1ec1u n\u00e0y c\u00f3 th\u1ec3 c\u00f3 t\u00e1c \u0111\u1ed9ng \u0111\u00e1ng k\u1ec3 \u0111\u1ebfn vi\u1ec7c ph\u00e2n t\u00edch v\u00e0 l\u1eadp m\u00f4 h\u00ecnh. Qu\u00e1 tr\u00ecnh t\u00ednh to\u00e1n d\u1eef li\u1ec7u th\u01b0\u1eddng bao g\u1ed3m vi\u1ec7c x\u00e1c \u0111\u1ecbnh c\u00e1c gi\u00e1 tr\u1ecb c\u00f2n thi\u1ebfu, ch\u1ecdn ph\u01b0\u01a1ng ph\u00e1p t\u00ednh to\u00e1n th\u00edch h\u1ee3p v\u00e0 sau \u0111\u00f3 t\u1ea1o ra c\u00e1c gi\u00e1 tr\u1ecb \u01b0\u1edbc t\u00ednh.<\/p>\n<h2>C\u1ea5u tr\u00fac b\u00ean trong v\u00e0 c\u00e1ch th\u1ee9c ho\u1ea1t \u0111\u1ed9ng<\/h2>\n<p>C\u00e1c k\u1ef9 thu\u1eadt x\u1eed l\u00fd d\u1eef li\u1ec7u c\u00f3 th\u1ec3 \u0111\u01b0\u1ee3c ph\u00e2n lo\u1ea1i th\u00e0nh nhi\u1ec1u lo\u1ea1i, bao g\u1ed3m:<\/p>\n<ol>\n<li><strong>Ngh\u0129a l\u00e0 s\u1ef1 bu\u1ed9c t\u1ed9i<\/strong>: Thay th\u1ebf c\u00e1c gi\u00e1 tr\u1ecb b\u1ecb thi\u1ebfu b\u1eb1ng gi\u00e1 tr\u1ecb trung b\u00ecnh c\u1ee7a d\u1eef li\u1ec7u c\u00f3 s\u1eb5n cho bi\u1ebfn \u0111\u00f3.<\/li>\n<li><strong>S\u1ef1 bu\u1ed9c t\u1ed9i trung b\u00ecnh<\/strong>: Thay th\u1ebf c\u00e1c gi\u00e1 tr\u1ecb b\u1ecb thi\u1ebfu b\u1eb1ng gi\u00e1 tr\u1ecb trung b\u00ecnh c\u1ee7a d\u1eef li\u1ec7u c\u00f3 s\u1eb5n cho bi\u1ebfn \u0111\u00f3.<\/li>\n<li><strong>Ch\u1ebf \u0111\u1ed9 \u00e1p \u0111\u1eb7t<\/strong>: Thay th\u1ebf c\u00e1c gi\u00e1 tr\u1ecb b\u1ecb thi\u1ebfu b\u1eb1ng ch\u1ebf \u0111\u1ed9 (gi\u00e1 tr\u1ecb th\u01b0\u1eddng xuy\u00ean nh\u1ea5t) c\u1ee7a d\u1eef li\u1ec7u c\u00f3 s\u1eb5n cho bi\u1ebfn \u0111\u00f3.<\/li>\n<li><strong>H\u1ed3i quy quy \u0111\u1ecbnh<\/strong>: D\u1ef1 \u0111o\u00e1n c\u00e1c gi\u00e1 tr\u1ecb c\u00f2n thi\u1ebfu b\u1eb1ng ph\u00e2n t\u00edch h\u1ed3i quy d\u1ef1a tr\u00ean c\u00e1c bi\u1ebfn kh\u00e1c.<\/li>\n<li><strong>K-h\u00e0ng x\u00f3m g\u1ea7n nh\u1ea5t (KNN)<\/strong>: D\u1ef1 \u0111o\u00e1n c\u00e1c gi\u00e1 tr\u1ecb c\u00f2n thi\u1ebfu d\u1ef1a tr\u00ean gi\u00e1 tr\u1ecb c\u1ee7a c\u00e1c l\u00e2n c\u1eadn g\u1ea7n nh\u1ea5t trong kh\u00f4ng gian d\u1eef li\u1ec7u.<\/li>\n<li><strong>Nhi\u1ec1u s\u1ef1 thay \u0111\u1ed5i<\/strong>: T\u1ea1o nhi\u1ec1u b\u1ed9 d\u1eef li\u1ec7u \u0111\u01b0\u1ee3c quy \u0111\u1ecbnh \u0111\u1ec3 t\u00ednh \u0111\u1ebfn s\u1ef1 kh\u00f4ng ch\u1eafc ch\u1eafn trong qu\u00e1 tr\u00ecnh quy \u0111\u1ecbnh.<\/li>\n<\/ol>\n<p>Vi\u1ec7c l\u1ef1a ch\u1ecdn ph\u01b0\u01a1ng ph\u00e1p t\u00ednh to\u00e1n ph\u1ee5 thu\u1ed9c v\u00e0o b\u1ea3n ch\u1ea5t c\u1ee7a d\u1eef li\u1ec7u v\u00e0 m\u1ee5c ti\u00eau ph\u00e2n t\u00edch. M\u1ed7i k\u1ef9 thu\u1eadt \u0111\u1ec1u c\u00f3 \u0111i\u1ec3m m\u1ea1nh v\u00e0 \u0111i\u1ec3m y\u1ebfu, v\u00e0 vi\u1ec7c l\u1ef1a ch\u1ecdn ph\u01b0\u01a1ng ph\u00e1p th\u00edch h\u1ee3p l\u00e0 \u0111i\u1ec1u c\u1ea7n thi\u1ebft \u0111\u1ec3 c\u00f3 \u0111\u01b0\u1ee3c k\u1ebft qu\u1ea3 ch\u00ednh x\u00e1c v\u00e0 \u0111\u00e1ng tin c\u1eady.<\/p>\n<h2>C\u00e1c t\u00ednh n\u0103ng ch\u00ednh c\u1ee7a vi\u1ec7c t\u00ednh to\u00e1n d\u1eef li\u1ec7u<\/h2>\n<p>Vi\u1ec7c c\u1eaft b\u1ecf d\u1eef li\u1ec7u mang l\u1ea1i m\u1ed9t s\u1ed1 l\u1ee3i \u00edch ch\u00ednh, bao g\u1ed3m:<\/p>\n<ul>\n<li>Ch\u1ea5t l\u01b0\u1ee3ng d\u1eef li\u1ec7u n\u00e2ng cao: B\u1eb1ng c\u00e1ch \u0111i\u1ec1n v\u00e0o c\u00e1c gi\u00e1 tr\u1ecb c\u00f2n thi\u1ebfu, vi\u1ec7c t\u00ednh to\u00e1n d\u1eef li\u1ec7u s\u1ebd c\u1ea3i thi\u1ec7n t\u00ednh \u0111\u1ea7y \u0111\u1ee7 c\u1ee7a c\u00e1c b\u1ed9 d\u1eef li\u1ec7u, khi\u1ebfn ch\u00fang tr\u1edf n\u00ean \u0111\u00e1ng tin c\u1eady h\u01a1n \u0111\u1ec3 ph\u00e2n t\u00edch.<\/li>\n<li>S\u1ee9c m\u1ea1nh th\u1ed1ng k\u00ea t\u1ed1t h\u01a1n: Vi\u1ec7c t\u00ednh to\u00e1n l\u00e0m t\u0103ng k\u00edch th\u01b0\u1edbc m\u1eabu, d\u1eabn \u0111\u1ebfn c\u00e1c ph\u00e2n t\u00edch th\u1ed1ng k\u00ea m\u1ea1nh m\u1ebd h\u01a1n v\u00e0 kh\u00e1i qu\u00e1t h\u00f3a k\u1ebft qu\u1ea3 t\u1ed1t h\u01a1n.<\/li>\n<li>B\u1ea3o to\u00e0n m\u1ed1i quan h\u1ec7: Ph\u01b0\u01a1ng ph\u00e1p quy n\u1ea1p nh\u1eb1m m\u1ee5c \u0111\u00edch duy tr\u00ec m\u1ed1i quan h\u1ec7 gi\u1eefa c\u00e1c bi\u1ebfn, \u0111\u1ea3m b\u1ea3o t\u00ednh to\u00e0n v\u1eb9n c\u1ee7a c\u1ea5u tr\u00fac d\u1eef li\u1ec7u.<\/li>\n<\/ul>\n<p>Tuy nhi\u00ean, vi\u1ec7c c\u1eaft b\u1ecf d\u1eef li\u1ec7u c\u0169ng \u0111i k\u00e8m v\u1edbi nh\u1eefng th\u00e1ch th\u1ee9c, ch\u1eb3ng h\u1ea1n nh\u01b0 c\u00f3 kh\u1ea3 n\u0103ng g\u00e2y ra sai l\u1ec7ch n\u1ebfu m\u00f4 h\u00ecnh c\u1eaft b\u1ecf b\u1ecb x\u00e1c \u0111\u1ecbnh sai ho\u1eb7c n\u1ebfu d\u1eef li\u1ec7u b\u1ecb thi\u1ebfu kh\u00f4ng b\u1ecb thi\u1ebfu m\u1ed9t c\u00e1ch ng\u1eabu nhi\u00ean (MNAR). Nh\u1eefng th\u00e1ch th\u1ee9c n\u00e0y c\u1ea7n ph\u1ea3i \u0111\u01b0\u1ee3c xem x\u00e9t c\u1ea9n th\u1eadn trong qu\u00e1 tr\u00ecnh bu\u1ed9c t\u1ed9i.<\/p>\n<h2>C\u00e1c lo\u1ea1i d\u1eef li\u1ec7u \u00e1p \u0111\u1eb7t<\/h2>\n<p>B\u1ea3ng d\u01b0\u1edbi \u0111\u00e2y t\u00f3m t\u1eaft c\u00e1c lo\u1ea1i ph\u01b0\u01a1ng ph\u00e1p t\u00ednh to\u00e1n d\u1eef li\u1ec7u kh\u00e1c nhau:<\/p>\n<table>\n<thead>\n<tr>\n<th>Ph\u01b0\u01a1ng ph\u00e1p quy k\u1ebft<\/th>\n<th>S\u1ef1 mi\u00eau t\u1ea3<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>Ngh\u0129a l\u00e0 s\u1ef1 bu\u1ed9c t\u1ed9i<\/td>\n<td>Thay th\u1ebf c\u00e1c gi\u00e1 tr\u1ecb b\u1ecb thi\u1ebfu b\u1eb1ng gi\u00e1 tr\u1ecb trung b\u00ecnh c\u1ee7a d\u1eef li\u1ec7u c\u00f3 s\u1eb5n.<\/td>\n<\/tr>\n<tr>\n<td>S\u1ef1 bu\u1ed9c t\u1ed9i trung b\u00ecnh<\/td>\n<td>Thay th\u1ebf c\u00e1c gi\u00e1 tr\u1ecb b\u1ecb thi\u1ebfu b\u1eb1ng gi\u00e1 tr\u1ecb trung b\u00ecnh c\u1ee7a d\u1eef li\u1ec7u c\u00f3 s\u1eb5n.<\/td>\n<\/tr>\n<tr>\n<td>Ch\u1ebf \u0111\u1ed9 \u00e1p \u0111\u1eb7t<\/td>\n<td>Thay th\u1ebf c\u00e1c gi\u00e1 tr\u1ecb b\u1ecb thi\u1ebfu b\u1eb1ng ch\u1ebf \u0111\u1ed9 c\u1ee7a d\u1eef li\u1ec7u c\u00f3 s\u1eb5n.<\/td>\n<\/tr>\n<tr>\n<td>H\u1ed3i quy quy \u0111\u1ecbnh<\/td>\n<td>D\u1ef1 \u0111o\u00e1n c\u00e1c gi\u00e1 tr\u1ecb c\u00f2n thi\u1ebfu b\u1eb1ng c\u00e1ch s\u1eed d\u1ee5ng ph\u00e2n t\u00edch h\u1ed3i quy.<\/td>\n<\/tr>\n<tr>\n<td>KNN tranh ch\u1ea5p<\/td>\n<td>D\u1ef1 \u0111o\u00e1n c\u00e1c gi\u00e1 tr\u1ecb c\u00f2n thi\u1ebfu d\u1ef1a tr\u00ean c\u00e1c h\u00e0ng x\u00f3m g\u1ea7n nh\u1ea5t.<\/td>\n<\/tr>\n<tr>\n<td>Nhi\u1ec1u s\u1ef1 thay \u0111\u1ed5i<\/td>\n<td>T\u1ea1o nhi\u1ec1u b\u1ed9 d\u1eef li\u1ec7u \u0111\u01b0\u1ee3c quy \u0111\u1ecbnh \u0111\u1ec3 gi\u1ea3i th\u00edch cho s\u1ef1 kh\u00f4ng ch\u1eafc ch\u1eafn.<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<h2>S\u1eed d\u1ee5ng, v\u1ea5n \u0111\u1ec1 v\u00e0 gi\u1ea3i ph\u00e1p<\/h2>\n<p>Vi\u1ec7c x\u1eed l\u00fd d\u1eef li\u1ec7u t\u00ecm th\u1ea5y c\u00e1c \u1ee9ng d\u1ee5ng trong c\u00e1c l\u0129nh v\u1ef1c kh\u00e1c nhau, bao g\u1ed3m:<\/p>\n<ul>\n<li><strong>Ch\u0103m s\u00f3c s\u1ee9c kh\u1ecfe<\/strong>: Cung c\u1ea5p d\u1eef li\u1ec7u b\u1ec7nh nh\u00e2n b\u1ecb thi\u1ebfu \u0111\u1ec3 h\u1ed7 tr\u1ee3 nghi\u00ean c\u1ee9u l\u00e2m s\u00e0ng v\u00e0 ra quy\u1ebft \u0111\u1ecbnh.<\/li>\n<li><strong>T\u00e0i ch\u00ednh<\/strong>: \u0110i\u1ec1n c\u00e1c d\u1eef li\u1ec7u t\u00e0i ch\u00ednh c\u00f2n thi\u1ebfu \u0111\u1ec3 ph\u00e2n t\u00edch r\u1ee7i ro v\u00e0 qu\u1ea3n l\u00fd danh m\u1ee5c \u0111\u1ea7u t\u01b0 m\u1ed9t c\u00e1ch ch\u00ednh x\u00e1c.<\/li>\n<li><strong>Khoa h\u1ecdc X\u00e3 h\u1ed9i<\/strong>: Vi\u1ec7c quy n\u1ea1p \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng trong c\u00e1c cu\u1ed9c kh\u1ea3o s\u00e1t v\u00e0 nghi\u00ean c\u1ee9u nh\u00e2n kh\u1ea9u h\u1ecdc \u0111\u1ec3 x\u1eed l\u00fd c\u00e1c c\u00e2u tr\u1ea3 l\u1eddi c\u00f2n thi\u1ebfu.<\/li>\n<\/ul>\n<p>Tuy nhi\u00ean, qu\u00e1 tr\u00ecnh x\u1eed l\u00fd d\u1eef li\u1ec7u kh\u00f4ng ph\u1ea3i l\u00e0 kh\u00f4ng c\u00f3 nh\u1eefng th\u00e1ch th\u1ee9c. M\u1ed9t s\u1ed1 v\u1ea5n \u0111\u1ec1 ph\u1ed5 bi\u1ebfn bao g\u1ed3m:<\/p>\n<ul>\n<li><strong>L\u1ef1a ch\u1ecdn ph\u01b0\u01a1ng ph\u00e1p t\u00ednh to\u00e1n<\/strong>: L\u1ef1a ch\u1ecdn ph\u01b0\u01a1ng ph\u00e1p th\u00edch h\u1ee3p d\u1ef1a tr\u00ean \u0111\u1eb7c \u0111i\u1ec3m d\u1eef li\u1ec7u.<\/li>\n<li><strong>Hi\u1ec7u l\u1ef1c c\u1ee7a d\u1eef li\u1ec7u \u0111\u01b0\u1ee3c \u0111\u01b0a ra<\/strong>: \u0110\u1ea3m b\u1ea3o c\u00e1c gi\u00e1 tr\u1ecb \u0111\u01b0\u1ee3c t\u00ednh to\u00e1n th\u1ec3 hi\u1ec7n ch\u00ednh x\u00e1c c\u00e1c gi\u00e1 tr\u1ecb th\u1ef1c c\u00f2n thi\u1ebfu.<\/li>\n<li><strong>Chi ph\u00ed t\u00ednh to\u00e1n<\/strong>: M\u1ed9t s\u1ed1 ph\u01b0\u01a1ng ph\u00e1p t\u00ednh to\u00e1n c\u00f3 th\u1ec3 c\u1ea7n t\u00ednh to\u00e1n chuy\u00ean s\u00e2u \u0111\u1ed1i v\u1edbi c\u00e1c t\u1eadp d\u1eef li\u1ec7u l\u1edbn.<\/li>\n<\/ul>\n<p>\u0110\u1ec3 gi\u1ea3i quy\u1ebft nh\u1eefng v\u1ea5n \u0111\u1ec1 n\u00e0y, c\u00e1c nh\u00e0 nghi\u00ean c\u1ee9u li\u00ean t\u1ee5c ph\u00e1t tri\u1ec3n v\u00e0 c\u1ea3i ti\u1ebfn c\u00e1c k\u1ef9 thu\u1eadt quy n\u1ea1p, c\u1ed1 g\u1eafng t\u00ecm ra c\u00e1c ph\u01b0\u01a1ng ph\u00e1p ch\u00ednh x\u00e1c v\u00e0 hi\u1ec7u qu\u1ea3 h\u01a1n.<\/p>\n<h2>\u0110\u1eb7c \u0111i\u1ec3m v\u00e0 so s\u00e1nh<\/h2>\n<p>D\u01b0\u1edbi \u0111\u00e2y l\u00e0 m\u1ed9t s\u1ed1 \u0111\u1eb7c \u0111i\u1ec3m ch\u00ednh v\u00e0 so s\u00e1nh c\u1ee7a vi\u1ec7c c\u1eaft b\u1ecf d\u1eef li\u1ec7u:<\/p>\n<table>\n<thead>\n<tr>\n<th>\u0111\u1eb7c tr\u01b0ng<\/th>\n<th>Nh\u1eadp d\u1eef li\u1ec7u<\/th>\n<th>N\u1ed9i suy d\u1eef li\u1ec7u<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>M\u1ee5c \u0111\u00edch<\/td>\n<td>\u01af\u1edbc t\u00ednh c\u00e1c gi\u00e1 tr\u1ecb c\u00f2n thi\u1ebfu trong t\u1eadp d\u1eef li\u1ec7u<\/td>\n<td>\u01af\u1edbc t\u00ednh gi\u00e1 tr\u1ecb gi\u1eefa c\u00e1c \u0111i\u1ec3m d\u1eef li\u1ec7u hi\u1ec7n c\u00f3<\/td>\n<\/tr>\n<tr>\n<td>Kh\u1ea3 n\u0103ng \u1ee9ng d\u1ee5ng<\/td>\n<td>Thi\u1ebfu d\u1eef li\u1ec7u d\u01b0\u1edbi nhi\u1ec1u h\u00ecnh th\u1ee9c kh\u00e1c nhau<\/td>\n<td>D\u1eef li\u1ec7u chu\u1ed7i th\u1eddi gian c\u00f3 kho\u1ea3ng tr\u1ed1ng<\/td>\n<\/tr>\n<tr>\n<td>K\u1ef9 thu\u1eadt<\/td>\n<td>Gi\u00e1 tr\u1ecb trung b\u00ecnh, trung v\u1ecb, h\u1ed3i quy, KNN, v.v.<\/td>\n<td>Tuy\u1ebfn t\u00ednh, spline, \u0111a th\u1ee9c, v.v.<\/td>\n<\/tr>\n<tr>\n<td>T\u1eadp trung<\/td>\n<td>T\u00ednh \u0111\u1ea7y \u0111\u1ee7 c\u1ee7a d\u1eef li\u1ec7u<\/td>\n<td>\u0110\u1ed9 tr\u01a1n tru v\u00e0 t\u00ednh li\u00ean t\u1ee5c c\u1ee7a d\u1eef li\u1ec7u<\/td>\n<\/tr>\n<tr>\n<td>Ph\u1ee5 thu\u1ed9c d\u1eef li\u1ec7u<\/td>\n<td>C\u00f3 th\u1ec3 s\u1eed d\u1ee5ng m\u1ed1i quan h\u1ec7 gi\u1eefa c\u00e1c bi\u1ebfn<\/td>\n<td>Th\u01b0\u1eddng d\u1ef1a v\u00e0o th\u1ee9 t\u1ef1 c\u1ee7a c\u00e1c \u0111i\u1ec3m d\u1eef li\u1ec7u<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<h2>Quan \u0111i\u1ec3m v\u00e0 c\u00f4ng ngh\u1ec7 t\u01b0\u01a1ng lai<\/h2>\n<p>Khi c\u00f4ng ngh\u1ec7 ti\u1ebfn b\u1ed9, c\u00e1c k\u1ef9 thu\u1eadt x\u1eed l\u00fd d\u1eef li\u1ec7u d\u1ef1 ki\u1ebfn s\u1ebd tr\u1edf n\u00ean ph\u1ee9c t\u1ea1p v\u00e0 ch\u00ednh x\u00e1c h\u01a1n. C\u00e1c thu\u1eadt to\u00e1n h\u1ecdc m\u00e1y, ch\u1eb3ng h\u1ea1n nh\u01b0 m\u00f4 h\u00ecnh h\u1ecdc s\u00e2u v\u00e0 t\u1ed5ng qu\u00e1t, c\u00f3 th\u1ec3 \u0111\u00f3ng m\u1ed9t vai tr\u00f2 quan tr\u1ecdng h\u01a1n trong vi\u1ec7c x\u1eed l\u00fd d\u1eef li\u1ec7u b\u1ecb thi\u1ebfu. Ngo\u00e0i ra, c\u00e1c ph\u01b0\u01a1ng ph\u00e1p quy n\u1ea1p c\u00f3 th\u1ec3 k\u1ebft h\u1ee3p ki\u1ebfn th\u1ee9c v\u00e0 b\u1ed1i c\u1ea3nh c\u1ee5 th\u1ec3 c\u1ee7a t\u1eebng mi\u1ec1n \u0111\u1ec3 c\u1ea3i thi\u1ec7n \u0111\u1ed9 ch\u00ednh x\u00e1c h\u01a1n n\u1eefa.<\/p>\n<h2>M\u00e1y ch\u1ee7 proxy v\u00e0 d\u1eef li\u1ec7u<\/h2>\n<p>Vi\u1ec7c x\u1eed l\u00fd d\u1eef li\u1ec7u c\u00f3 th\u1ec3 li\u00ean quan gi\u00e1n ti\u1ebfp \u0111\u1ebfn m\u00e1y ch\u1ee7 proxy. M\u00e1y ch\u1ee7 proxy \u0111\u00f3ng vai tr\u00f2 trung gian gi\u1eefa ng\u01b0\u1eddi d\u00f9ng v\u00e0 internet, cung c\u1ea5p nhi\u1ec1u ch\u1ee9c n\u0103ng kh\u00e1c nhau nh\u01b0 \u1ea9n danh, b\u1ea3o m\u1eadt v\u00e0 b\u1ecf qua c\u00e1c h\u1ea1n ch\u1ebf n\u1ed9i dung. M\u1eb7c d\u00f9 b\u1ea3n th\u00e2n vi\u1ec7c x\u1eed l\u00fd d\u1eef li\u1ec7u c\u00f3 th\u1ec3 kh\u00f4ng \u0111\u01b0\u1ee3c li\u00ean k\u1ebft tr\u1ef1c ti\u1ebfp v\u1edbi m\u00e1y ch\u1ee7 proxy, vi\u1ec7c ph\u00e2n t\u00edch v\u00e0 x\u1eed l\u00fd d\u1eef li\u1ec7u \u0111\u01b0\u1ee3c thu th\u1eadp th\u00f4ng qua m\u00e1y ch\u1ee7 proxy c\u00f3 th\u1ec3 \u0111\u01b0\u1ee3c h\u01b0\u1edfng l\u1ee3i t\u1eeb c\u00e1c k\u1ef9 thu\u1eadt x\u1eed l\u00fd d\u1eef li\u1ec7u khi x\u1eed l\u00fd c\u00e1c \u0111i\u1ec3m d\u1eef li\u1ec7u kh\u00f4ng \u0111\u1ea7y \u0111\u1ee7 ho\u1eb7c b\u1ecb thi\u1ebfu.<\/p>\n<h2>Li\u00ean k\u1ebft li\u00ean quan<\/h2>\n<p>\u0110\u1ec3 bi\u1ebft th\u00eam th\u00f4ng tin v\u1ec1 vi\u1ec7c x\u1eed l\u00fd d\u1eef li\u1ec7u, b\u1ea1n c\u00f3 th\u1ec3 tham kh\u1ea3o c\u00e1c t\u00e0i nguy\u00ean sau:<\/p>\n<ol>\n<li><a href=\"https:\/\/www.wiley.com\/en-us\/Missing+Data%3A+Analysis+and+Design%2C+2nd+Edition-p-9780470526794\" target=\"_new\" rel=\"noopener nofollow\">D\u1eef li\u1ec7u b\u1ecb thi\u1ebfu: Ph\u00e2n t\u00edch v\u00e0 thi\u1ebft k\u1ebf c\u1ee7a Roderick JA Little v\u00e0 Donald B. Rubin<\/a><\/li>\n<li><a href=\"https:\/\/journals.sagepub.com\/doi\/10.1177\/096228029300200402\" target=\"_new\" rel=\"noopener nofollow\">Nhi\u1ec1u l\u00fd do cho vi\u1ec7c kh\u00f4ng ph\u1ea3n h\u1ed3i trong c\u00e1c cu\u1ed9c kh\u1ea3o s\u00e1t c\u1ee7a Donald B. Rubin<\/a><\/li>\n<li><a href=\"https:\/\/www.ncbi.nlm.nih.gov\/pmc\/articles\/PMC3668100\/\" target=\"_new\" rel=\"noopener nofollow\">Gi\u1edbi thi\u1ec7u v\u1ec1 vi\u1ec7c x\u00e1c \u0111\u1ecbnh d\u1eef li\u1ec7u v\u00e0 nh\u1eefng th\u00e1ch th\u1ee9c c\u1ee7a n\u00f3<\/a><\/li>\n<\/ol>\n<p>T\u00f3m l\u1ea1i, vi\u1ec7c x\u1eed l\u00fd d\u1eef li\u1ec7u \u0111\u00f3ng m\u1ed9t vai tr\u00f2 quan tr\u1ecdng trong vi\u1ec7c x\u1eed l\u00fd d\u1eef li\u1ec7u b\u1ecb thi\u1ebfu trong b\u1ed9 d\u1eef li\u1ec7u, c\u1ea3i thi\u1ec7n ch\u1ea5t l\u01b0\u1ee3ng d\u1eef li\u1ec7u v\u00e0 cho ph\u00e9p ph\u00e2n t\u00edch ch\u00ednh x\u00e1c h\u01a1n. V\u1edbi nh\u1eefng ti\u1ebfn b\u1ed9 v\u1ec1 nghi\u00ean c\u1ee9u v\u00e0 c\u00f4ng ngh\u1ec7 \u0111ang di\u1ec5n ra, c\u00e1c k\u1ef9 thu\u1eadt x\u1eed l\u00fd d\u1eef li\u1ec7u c\u00f3 th\u1ec3 s\u1ebd ph\u00e1t tri\u1ec3n, d\u1eabn \u0111\u1ebfn k\u1ebft qu\u1ea3 x\u1eed l\u00fd d\u1eef li\u1ec7u th\u1eadm ch\u00ed c\u00f2n t\u1ed1t h\u01a1n v\u00e0 h\u1ed7 tr\u1ee3 c\u00e1c l\u0129nh v\u1ef1c kh\u00e1c nhau trong c\u00e1c ng\u00e0nh kh\u00e1c nhau.<\/p>","protected":false},"featured_media":468110,"menu_order":0,"template":"","meta":{"_acf_changed":false,"content-type":"","inline_featured_image":false,"footnotes":""},"class_list":["post-476644","wiki","type-wiki","status-publish","has-post-thumbnail","hentry"],"acf":{"faq_title":"Frequently Asked Questions about <mark>Data Imputation: Bridging the Gaps in Information<\/mark>","faq_items":[{"question":"What is data imputation and why is it important?","answer":"<p>Data imputation is a statistical technique used to fill in missing or incomplete data points within a dataset with estimated values. It is important because missing data can lead to biased analysis and inaccurate modeling. Imputation enhances data quality, ensuring more reliable and comprehensive results.<\/p>"},{"question":"How did data imputation evolve over time?","answer":"<p>The concept of data imputation has been around for centuries, but it gained more prominence with the rise of computers and statistical analysis in the 20th century. Donald B. Rubin's work on multiple imputation techniques in the 1970s was a significant milestone in its development.<\/p>"},{"question":"What are the main types of data imputation methods?","answer":"<p>Data imputation methods can be categorized into several types, including mean imputation, median imputation, mode imputation, regression imputation, K-nearest neighbors (KNN) imputation, and multiple imputation.<\/p>"},{"question":"How does data imputation work internally?","answer":"<p>Data imputation works by identifying missing values, selecting an appropriate imputation method, and generating estimated values based on the available data. Each method has its strengths and is chosen based on the data characteristics and analysis goals.<\/p>"},{"question":"What are the key benefits of data imputation?","answer":"<p>Data imputation offers several benefits, including enhanced data quality, increased statistical power, and preservation of relationships between variables. It leads to more accurate analysis and better decision-making.<\/p>"},{"question":"What challenges are associated with data imputation?","answer":"<p>Some challenges of data imputation include selecting the right imputation method, ensuring the validity of imputed data, and dealing with computationally intensive techniques for large datasets.<\/p>"},{"question":"In what areas is data imputation applied?","answer":"<p>Data imputation finds applications in various domains, including healthcare, finance, and social sciences, where missing data can impact research and analysis.<\/p>"},{"question":"How does data imputation compare with data interpolation?","answer":"<p>Data imputation focuses on estimating missing values within a dataset, while data interpolation aims to estimate values between existing data points, often in time-series data with gaps.<\/p>"},{"question":"What does the future hold for data imputation?","answer":"<p>As technology advances, data imputation techniques are expected to become more sophisticated, incorporating machine learning algorithms and domain-specific knowledge for better accuracy and reliability.<\/p>"},{"question":"How are proxy servers related to data imputation?","answer":"<p>While data imputation itself may not be directly tied to proxy servers, the analysis and processing of data collected through proxy servers may benefit from imputation techniques when dealing with incomplete or missing data points.<\/p>"}]},"_links":{"self":[{"href":"https:\/\/oneproxy.pro\/vn\/wp-json\/wp\/v2\/wiki\/476644","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/oneproxy.pro\/vn\/wp-json\/wp\/v2\/wiki"}],"about":[{"href":"https:\/\/oneproxy.pro\/vn\/wp-json\/wp\/v2\/types\/wiki"}],"version-history":[{"count":0,"href":"https:\/\/oneproxy.pro\/vn\/wp-json\/wp\/v2\/wiki\/476644\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/oneproxy.pro\/vn\/wp-json\/wp\/v2\/media\/468110"}],"wp:attachment":[{"href":"https:\/\/oneproxy.pro\/vn\/wp-json\/wp\/v2\/media?parent=476644"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}