{"id":25994,"date":"2023-12-07T02:19:00","date_gmt":"2023-12-07T02:19:00","guid":{"rendered":"https:\/\/masterskills.org\/blog\/chon-mau-phan-to-stratified-sampling-trong-thong-ke-la-gi.html"},"modified":"2023-12-22T11:24:21","modified_gmt":"2023-12-22T04:24:21","slug":"chon-mau-phan-to-stratified-sampling-trong-thong-ke-la-gi","status":"publish","type":"post","link":"https:\/\/masterskills.org\/blog\/chon-mau-phan-to-stratified-sampling-trong-thong-ke-la-gi.html","title":{"rendered":"Ch\u1ecdn m\u1eabu ph\u00e2n t\u1ed5 (Stratified sampling) trong th\u1ed1ng k\u00ea l\u00e0 g\u00ec?"},"content":{"rendered":"
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H\u00ecnh minh h\u1ecda. Ngu\u1ed3n: DataScience Made Simple<\/p>\n<\/div>\n<\/div>\n

Ch\u1ecdn m\u1eabu ph\u00e2n t\u1ed5<\/font><\/h2>\n

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

Ch\u1ecdn m\u1eabu ph\u00e2n t\u1ed5 <\/b>hay ch\u1ecdn m\u1eabu ph\u00e2n t\u1ea7ng<\/b>\u00a0trong ti\u1ebfng Anh l\u00e0\u00a0stratified sampling<\/b>.<\/p>\n

Ch\u1ecdn m\u1eabu ph\u00e2n t\u1ed5<\/b> l\u00e0 ph\u01b0\u01a1ng ph\u00e1p m\u00e0 c\u00e1c \u0111\u01a1n v\u1ecb m\u1eabu \u0111\u01b0\u1ee3c ch\u1ecdn khi t\u1ed5ng th\u1ec3 chung \u0111\u00e3 \u0111\u01b0\u1ee3c ph\u00e2n chia th\u00e0nh c\u00e1c t\u1ed5 theo ti\u00eau th\u1ee9c li\u00ean quan tr\u1ef1c ti\u1ebfp \u0111\u1ebfn m\u1ee5c \u0111\u00edch nghi\u00ean c\u1ee9u. Vi\u1ec7c ch\u1ecdn c\u00e1c \u0111\u01a1n v\u1ecb t\u1eeb c\u00e1c t\u1ed5 \u0111\u01b0\u1ee3c ti\u1ebfn h\u00e0nh theo ph\u01b0\u01a1ng ph\u00e1p ch\u1ecdn ng\u1eabu nhi\u00ean.\u00a0<\/p>\n

C\u00e1c b\u01b0\u1edbc ch\u1ecdn m\u1eabu ph\u00e2n t\u1ea7ng<\/font><\/h3>\n

Tr\u00ecnh t\u1ef1 \u0111\u01b0\u1ee3c ti\u1ebfn h\u00e0nh nh\u01b0 sau:<\/b><\/p>\n

– Tr\u01b0\u1edbc h\u1ebft ph\u00e2n chia t\u1ed5ng th\u1ec3 th\u00e0nh c\u00e1c t\u1ed5 c\u0103n c\u1ee9 v\u00e0o ti\u00eau th\u1ee9c c\u00f3 li\u00ean quan ch\u1eb7t ch\u1ebd \u0111\u1ebfn m\u1ee5c \u0111\u00edch nghi\u00ean c\u1ee9u;<\/p>\n

– T\u1eeb m\u1ed7i b\u1ed9 ph\u1eadn hay m\u1ed7i t\u1ed5 ch\u1ecdn ra m\u1ed9t s\u1ed1 \u0111\u01a1n v\u1ecb m\u1eabu;<\/p>\n

– X\u00e1c \u0111\u1ecbnh s\u1ed1 \u0111\u01a1n v\u1ecb c\u1ee7a m\u1ed7i t\u1ed5 \u0111\u01b0\u1ee3c ch\u1ecdn v\u00e0o m\u1eabu \u0111\u01b0\u1ee3c g\u1ecdi l\u00e0 ph\u00e2n b\u1ed5 m\u1eabu, c\u00f3 nhi\u1ec1u ph\u01b0\u01a1ng ph\u00e1p ph\u00e2n b\u1ed5 m\u1eabu kh\u00e1c nhau: c\u00f3 th\u1ec3 t\u1ec9 l\u1ec7 v\u1edbi qui m\u00f4 t\u1ed5 (ch\u1ecdn theo t\u1ec9 l\u1ec7), t\u1ec9 l\u1ec7 v\u1edbi c\u0103n b\u1eadc hai c\u1ee7a qui m\u00f4; ho\u1eb7c kh\u00f4ng t\u1ec9 l\u1ec7 v\u1edbi qui m\u00f4 t\u1ed5 (ch\u1ecdn kh\u00f4ng theo t\u1ec9 l\u1ec7), ph\u00e2n b\u1ed5 m\u1eabu Neyman (ph\u00e2n b\u1ed5 t\u1ed1i \u01b0u),…<\/p>\n

\u01afu \u0111i\u1ec3m<\/font><\/h3>\n

Ph\u01b0\u01a1ng ph\u00e1p ch\u1ecdn m\u1eabu n\u00e0y cho ph\u00e9p ch\u1ecdn \u0111\u01b0\u1ee3c t\u1ed5ng th\u1ec3 m\u1eabu c\u00f3 k\u1ebft c\u1ea5u g\u1ea7n gi\u1ed1ng v\u1edbi k\u1ebft c\u1ea5u c\u1ee7a t\u1ed5ng th\u1ec3 chung (trong tr\u01b0\u1eddng h\u1ee3p ch\u1ecdn theo t\u1ec9 l\u1ec7) n\u00ean t\u00ednh \u0111\u1ea1i bi\u1ec3u cao, sai s\u1ed1 ch\u1ecdn m\u1eabu nh\u1ecf. Ph\u01b0\u01a1ng ph\u00e1p n\u00e0y khoa h\u1ecdc h\u01a1n hai ph\u01b0\u01a1ng ph\u00e1p\u00a0ch\u1ecdn m\u1eabu ng\u1eabu nhi\u00ean \u0111\u01a1n gi\u1ea3n\u00a0v\u00e0\u00a0ch\u1ecdn m\u1eabu ng\u1eabu nhi\u00ean h\u1ec7 th\u1ed1ng\u00a0n\u00ean n\u00f3 \u0111\u01b0\u1ee3c \u00e1p d\u1ee5ng r\u1ed9ng r\u00e3i h\u01a1n, nh\u1ea5t l\u00e0 \u0111\u1ed1i v\u1edbi hi\u1ec7n t\u01b0\u1ee3ng c\u1ea7n \u0111i\u1ec1u tra c\u00f3 s\u1ed1 \u0111\u01a1n v\u1ecb t\u1ed5ng th\u1ec3 l\u1edbn kh\u00f4ng th\u1ec3 ch\u1ecdn theo ph\u01b0\u01a1ng ph\u00e1p ch\u1ecdn m\u00e1y m\u00f3c \u0111\u01b0\u1ee3c. Song c\u00e1ch ch\u1ecdn n\u00e0y \u0111\u00f2i h\u1ecfi ph\u1ea3i c\u00f3 s\u1eb5n c\u00e1c ngu\u1ed3n th\u00f4ng tin v\u1ec1 t\u1ed5ng th\u1ec3 v\u00e0 c\u00f3 ki\u1ebfn th\u1ee9c ph\u00e2n t\u1ed5.\u00a0<\/p>\n

Nguy\u00ean t\u1eafc ch\u1ecdn m\u1eabu ph\u00e2n t\u1ed5<\/font><\/h3>\n

Ph\u01b0\u01a1ng ph\u00e1p n\u00e0y ph\u1ea7n n\u00e0o c\u0169ng d\u1ef1a v\u00e0o nh\u1eefng kinh nghi\u1ec7m ph\u00e1n \u0111o\u00e1n ch\u1ee7 quan n\u00ean c\u1ea7n ph\u1ea3i tu\u00e2n theo nh\u1eefng nguy\u00ean t\u1eafc chung khi ti\u1ebfn h\u00e0nh ph\u00e2n t\u1ed5 nh\u01b0:<\/p>\n

– Trong m\u1ed7i t\u1ed5 ph\u1ea3i \u0111\u1ea3m b\u1ea3o t\u00ednh \u0111\u1ed3ng ch\u1ea5t;<\/p>\n

– S\u1ed1 t\u1ed5 kh\u00f4ng n\u00ean chia qu\u00e1 \u00edt ho\u1eb7c qu\u00e1 nhi\u1ec1u;<\/p>\n

– S\u1ed1 \u0111\u01a1n v\u1ecb m\u1eabu c\u1ee7a t\u1eebng t\u1ed5 ph\u1ea3i \u0111\u1ee7 l\u1edbn \u0111\u1ec3 \u0111\u1ea3m b\u1ea3o \u0111\u1ed9 tin c\u1eady cho suy r\u1ed9ng, hay \u01b0\u1edbc l\u01b0\u1ee3ng.<\/p>\n

V\u00ed d\u1ee5, trong tr\u01b0\u1eddng h\u1ee3p ch\u1ecdn m\u1eabu \u0111i\u1ec1u tra doanh nghi\u1ec7p: ng\u01b0\u1eddi ta s\u1ebd ti\u1ebfn h\u00e0nh ph\u00e2n chia c\u00e1c doanh nghi\u1ec7p theo qui m\u00f4 (l\u1edbn, v\u1eeba v\u00e0 nh\u1ecf), sau \u0111\u00f3 s\u1ebd ti\u1ebfn h\u00e0nh x\u00e1c \u0111\u1ecbnh k\u00edch th\u01b0\u1edbc m\u1eabu c\u1ee7a cu\u1ed9c \u0111i\u1ec1u tra v\u00e0 ti\u1ebfn h\u00e0nh ph\u00e2n b\u1ed5 c\u00e1c \u0111\u01a1n v\u1ecb cho m\u1ed7i lo\u1ea1i h\u00ecnh qui m\u00f4 doanh nghi\u1ec7p.\u00a0<\/p>\n

(Theo Gi\u00e1o tr\u00ecnh Th\u1ed1ng k\u00ea doanh nghi\u1ec7p, NXB \u0110\u1ea1i h\u1ecdc Kinh t\u1ebf qu\u1ed1c d\u00e2n<\/i>)<\/p>\n<\/p><\/div>\n","protected":false},"excerpt":{"rendered":"

\n Ch\u1ecdn m\u1eabu ph\u00e2n t\u1ed5 (ti\u1ebfng Anh: Stratified sampling) l\u00e0 ph\u01b0\u01a1ng ph\u00e1p m\u00e0 c\u00e1c \u0111\u01a1n v\u1ecb m\u1eabu \u0111\u01b0\u1ee3c ch\u1ecdn khi t\u1ed5ng th\u1ec3 chung \u0111\u00e3 \u0111\u01b0\u1ee3c ph\u00e2n chia th\u00e0nh c\u00e1c t\u1ed5 theo ti\u00eau th\u1ee9c li\u00ean quan tr\u1ef1c ti\u1ebfp \u0111\u1ebfn m\u1ee5c \u0111\u00edch nghi\u00ean c\u1ee9u.\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\/25994"}],"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=25994"}],"version-history":[{"count":0,"href":"https:\/\/masterskills.org\/blog\/wp-json\/wp\/v2\/posts\/25994\/revisions"}],"wp:attachment":[{"href":"https:\/\/masterskills.org\/blog\/wp-json\/wp\/v2\/media?parent=25994"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/masterskills.org\/blog\/wp-json\/wp\/v2\/categories?post=25994"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/masterskills.org\/blog\/wp-json\/wp\/v2\/tags?post=25994"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}