{"id":25258,"date":"2023-12-07T00:18:32","date_gmt":"2023-12-07T00:18:32","guid":{"rendered":"https:\/\/masterskills.org\/blog\/xac-suat-ket-hop-joint-probability-la-gi-phan-biet-xac-suat-ket-hop-va-xac-suat-co-dieu-kien.html"},"modified":"2023-12-22T10:08:50","modified_gmt":"2023-12-22T03:08:50","slug":"xac-suat-ket-hop-joint-probability-la-gi-phan-biet-xac-suat-ket-hop-va-xac-suat-co-dieu-kien","status":"publish","type":"post","link":"https:\/\/masterskills.org\/blog\/xac-suat-ket-hop-joint-probability-la-gi-phan-biet-xac-suat-ket-hop-va-xac-suat-co-dieu-kien.html","title":{"rendered":"X\u00e1c su\u1ea5t k\u1ebft h\u1ee3p (Joint Probability) l\u00e0 g\u00ec? Ph\u00e2n bi\u1ec7t X\u00e1c su\u1ea5t k\u1ebft h\u1ee3p v\u00e0 X\u00e1c su\u1ea5t c\u00f3 \u0111i\u1ec1u ki\u1ec7n"},"content":{"rendered":"<div class=\"vnbcbc-body vceditor-content wi-active\" data-role=\"content\">\n<figure class=\"VCSortableInPreviewMode\" type=\"Photo\" style=\"\">\n<div><\/div><figcaption class=\"PhotoCMS_Caption\">\n<p data-placeholder=\"[Nh\u1eadp ch\u00fa th\u00edch \u1ea3nh]\">Hi\u0300nh minh ho\u0323a. Ngu\u00f4\u0300n: Luminousmen.com<\/p>\n<\/figcaption><\/figure>\n<h2><font style=\"line-height: 22px; font-size: 22px;\" color=\"#3d85c6\">X\u00e1c su\u1ea5t k\u1ebft h\u1ee3p<\/font><\/h2>\n<p><b>Kha\u0301i ni\u00ea\u0323m<\/b><\/p>\n<p><b>X\u00e1c su\u1ea5t k\u1ebft h\u1ee3p <\/b>trong ti\u00ea\u0301ng Anh la\u0300 <b>Joint Probability<\/b>.<\/p>\n<p><b>X\u00e1c su\u1ea5t k\u1ebft h\u1ee3p<\/b> l\u00e0 m\u1ed9t th\u01b0\u1edbc \u0111o th\u1ed1ng k\u00ea t\u00ednh to\u00e1n kh\u1ea3 n\u0103ng hai bi\u1ebfn c\u1ed1 x\u1ea3y ra c\u00f9ng m\u1ed9t l\u00fac v\u00e0 t\u1ea1i c\u00f9ng m\u1ed9t th\u1eddi \u0111i\u1ec3m.\u00a0<\/p>\n<p>Gi\u1ea3 s\u1eed c\u00f3 bi\u1ebfn c\u1ed1 X v\u1edbi x\u00e1c su\u1ea5t x\u1ea3y ra n\u00f3 l\u00e0 P(X) v\u00e0 bi\u1ebfn c\u1ed1 Y v\u1edbi x\u00e1c su\u1ea5t x\u1ea3y ra n\u00f3 l\u00e0 P(Y).\u00a0<\/p>\n<p>X\u00e1c su\u1ea5t k\u1ebft h\u1ee3p l\u00e0 x\u00e1c su\u1ea5t c\u1ee7a bi\u1ebfn c\u1ed1 Y x\u1ea3y ra c\u00f9ng l\u00fac v\u1edbi bi\u1ebfn c\u1ed1 X.     K\u00ed hi\u1ec7u c\u1ee7a x\u00e1c su\u1ea5t k\u1ebft h\u1ee3p l\u00e0 <b>P(X\u2229Y) <\/b>ho\u1eb7c <b>P(XY)<\/b>.  \u00a0\u00a0<\/p>\n<p>C\u00e1c nh\u00e0 th\u1ed1ng k\u00ea v\u00e0 ph\u00e2n t\u00edch s\u1eed d\u1ee5ng x\u00e1c su\u1ea5t k\u1ebft h\u1ee3p khi quan s\u00e1t hai ho\u1eb7c nhi\u1ec1u bi\u1ebfn c\u1ed1 c\u00f3 th\u1ec3 x\u1ea3y ra c\u00f9ng l\u00fac.\u00a0<\/p>\n<p><i>V\u00ed d\u1ee5 x\u00e1c su\u1ea5t k\u1ebft h\u1ee3p kh\u1ea3 n\u0103ng\u00a0<\/i>ch\u1ec9 s\u1ed1 trung b\u00ecnh c\u00f4ng nghi\u1ec7p Dow Jones<i>\u00a0(DJIA) gi\u1ea3m k\u00e8m theo s\u1ef1 s\u1ee5t gi\u1ea3m gi\u00e1 c\u1ed5 phi\u1ebfu c\u1ee7a c\u00f4ng ty Microsoft, hay kh\u1ea3 n\u0103ng gi\u00e1 d\u1ea7u t\u0103ng l\u00ean c\u00f9ng l\u00fac khi gi\u00e1 tr\u1ecb \u0111\u1ed3ng \u0111\u00f4 la M\u1ef9 gi\u1ea3m .  \u00a0  \u00a0  \u00a0\u00a0<\/i><\/p>\n<h3><font style=\"line-height: 22px; font-size: 22px;\" color=\"#3d85c6\">\u0110\u1eb7c \u0111i\u1ec3m X\u00e1c su\u1ea5t k\u1ebft h\u1ee3p\u00a0<\/font><\/h3>\n<p>X\u00e1c su\u1ea5t l\u00e0 m\u1ed9t \u0111\u1ea1i l\u01b0\u1ee3ng th\u1ed1ng k\u00ea m\u00f4 t\u1ea3 kh\u1ea3 n\u0103ng x\u1ea3y ra m\u1ed9t bi\u1ebfn c\u1ed1 hay m\u1ed9t hi\u1ec7n t\u01b0\u1ee3ng. N\u00f3 \u0111\u01b0\u1ee3c bi\u1ec3u di\u1ec5n d\u01b0\u1edbi d\u1ea1ng s\u1ed1 ch\u1ea1y t\u1eeb 0 \u0111\u1ebfn 1, trong \u0111\u00f3 0 l\u00e0 kh\u00f4ng th\u1ec3 x\u1ea3y ra v\u00e0 1 l\u00e0 bi\u1ebfn c\u1ed1 nh\u1ea5t \u0111\u1ecbnh s\u1ebd x\u1ea3y ra.  \u00a0\u00a0<\/p>\n<p>V\u00ed d\u1ee5: m\u1ed9t b\u1ed9 b\u00e0i c\u00f3 52 l\u00e1, x\u00e1c su\u1ea5t r\u00fat l\u00e1 \u0111\u1ecf t\u1eeb b\u1ed9 b\u00e0i l\u00e0 26\/52 = 0,5 hay 50%, c\u00f3 ngh\u0129a l\u00e0 c\u01a1 h\u1ed9i r\u00fat ra l\u00e1 \u0111\u1ecf v\u00e0 l\u00e0 l\u00e1 \u0111en l\u00e0 b\u1eb1ng nhau v\u00ec c\u00f3 26 l\u00e1 m\u00e0u \u0111\u1ecf v\u00e0 26 l\u00e1 m\u00e0u \u0111en trong m\u1ed9t b\u1ed9 b\u00e0i.  \u00a0\u00a0<\/p>\n<p><b>X\u00e1c su\u1ea5t k\u1ebft h\u1ee3p <\/b>\u0111o l\u01b0\u1eddng kh\u1ea3 n\u0103ng x\u1ea3y ra hai bi\u1ebfn c\u1ed1 c\u00f9ng m\u1ed9t l\u00fac v\u00e0 ch\u1ec9 c\u00f3 th\u1ec3 \u00e1p d\u1ee5ng cho c\u00e1c t\u00ecnh hu\u1ed1ng c\u00f3 th\u1ec3 x\u1ea3y ra nhi\u1ec1u h\u01a1n m\u1ed9t quan s\u00e1t c\u00f9ng m\u1ed9t l\u00fac.\u00a0<\/p>\n<p>V\u00ed d\u1ee5: c\u00f9ng m\u1ed9t b\u1ed9 b\u00e0i g\u1ed3m 52 l\u00e1, <i>x\u00e1c su\u1ea5t k\u1ebft h\u1ee3p <\/i>c\u1ee7a vi\u1ec7c r\u00fat ra m\u1ed9t l\u00e1 b\u00e0i m\u00e0u \u0111\u1ecf v\u00e0 l\u00e0 s\u1ed1 6 l\u00e0 P(6\u2229\u0111\u1ecf) = 2\/52 = 1\/26 v\u00ec m\u1ed9t b\u1ed9 b\u00e0i c\u00f3 hai l\u00e1 6 \u0111\u1ecf l\u00e0 6 c\u01a1 v\u00e0 6.\u00a0<\/p>\n<p>Hay P(6\u2229\u0111\u1ecf) = P(6) * P(\u0111\u1ecf) = 4\/52 * 26\/52 = 1\/26.<\/p>\n<p>K\u00ed hi\u1ec7u \u2229 trong x\u00e1c su\u1ea5t k\u1ebft h\u1ee3p l\u00e0 giao \u0111i\u1ec3m.   X\u00e1c su\u1ea5t c\u00f9ng x\u1ea3y ra bi\u1ebfn c\u1ed1 X v\u00e0 bi\u1ebfn c\u1ed1 Y l\u00e0 \u0111i\u1ec3m giao nhau c\u1ee7a x\u00e1c su\u1ea5t x\u1ea3y ra bi\u1ebfn c\u1ed1 X v\u00e0 x\u00e1c su\u1ea5t x\u1ea3y ra bi\u1ebfn c\u1ed1 Y.\u00a0<\/p>\n<p>Do \u0111\u00f3, x\u00e1c su\u1ea5t k\u1ebft h\u1ee3p c\u0169ng \u0111\u01b0\u1ee3c g\u1ecdi l\u00e0 giao \u0111i\u1ec3m c\u1ee7a hai ho\u1eb7c nhi\u1ec1u bi\u1ebfn c\u1ed1.\u00a0<\/p>\n<p>S\u01a1 \u0111\u1ed3 Venn \u0111i\u1ec3m giao nhau c\u1ee7a hai bi\u1ebfn c\u1ed1 nh\u01b0 sau:  \u00a0<\/p>\n<figure class=\"VCSortableInPreviewMode\" type=\"Photo\" style=\"\">\n<div><\/div><figcaption class=\"PhotoCMS_Caption\">\n<p data-placeholder=\"[Nh\u1eadp ch\u00fa th\u00edch \u1ea3nh]\">Hi\u0300nh minh ho\u0323a. Ngu\u00f4\u0300n: Investopedia.com<\/p>\n<\/figcaption><\/figure>\n<p>T\u1eeb s\u01a1 \u0111\u1ed3 Venn \u1edf tr\u00ean, \u0111i\u1ec3m m\u00e0 c\u1ea3 hai v\u00f2ng tr\u00f2n tr\u00f9ng nhau \u0111\u01b0\u1ee3c g\u1ecdi l\u00e0 giao \u0111i\u1ec3m, \u1edf \u0111\u00f3 c\u00f3 hai quan s\u00e1t l\u00e0 l\u00e1 6 r\u00f4 v\u00e0 6 c\u01a1.  \u00a0\u00a0<\/p>\n<h3><font style=\"line-height: 22px; font-size: 22px;\" color=\"#3d85c6\">Ph\u00e2n bi\u1ec7t X\u00e1c su\u1ea5t k\u1ebft h\u1ee3p v\u00e0 X\u00e1c su\u1ea5t c\u00f3 \u0111i\u1ec1u ki\u1ec7n\u00a0<\/font><\/h3>\n<p>Kh\u00f4ng n\u00ean nh\u1ea7m l\u1eabn <b>x\u00e1c su\u1ea5t k\u1ebft h\u1ee3p <\/b>v\u1edbi x\u00e1c su\u1ea5t c\u00f3 \u0111i\u1ec1u ki\u1ec7n l\u00e0 x\u00e1c su\u1ea5t x\u1ea3y ra m\u1ed9t bi\u1ebfn c\u1ed1 n\u1ebfu c\u00f3 h\u00e0nh \u0111\u1ed9ng ho\u1eb7c bi\u1ebfn c\u1ed1 kh\u00e1c x\u1ea3y ra.\u00a0<\/p>\n<p><i>X\u00e1c su\u1ea5t c\u00f3 \u0111i\u1ec1u ki\u1ec7n<\/i> l\u00e0 c\u01a1 h\u1ed9i m\u1ed9t bi\u1ebfn c\u1ed1 x\u1ea3y ra v\u1edbi \u0111i\u1ec1u ki\u1ec7n l\u00e0 m\u1ed9t bi\u1ebfn c\u1ed1 kh\u00e1c x\u1ea3y ra.   V\u00ed d\u1ee5 t\u1eeb b\u1ed9 b\u00e0i, x\u00e1c su\u1ea5t b\u1ea1n nh\u1eadn \u0111\u01b0\u1ee3c l\u00e1 6 v\u1edbi \u0111i\u1ec1u ki\u1ec7n l\u00e1 b\u1ea1n r\u00fat \u0111\u01b0\u1ee3c l\u00e0 l\u00e1 \u0111\u1ecf l\u00e0 P(6\u2502\u0111\u1ecf) = 2\/26 = 1\/13 do c\u00f3 hai l\u00e1 6 trong s\u1ed1 26 l\u00e1 \u0111\u1ecf .  \u00a0\u00a0<\/p>\n<p><i>X\u00e1c su\u1ea5t k\u1ebft h\u1ee3p ch\u1ec9 kh\u1ea3 n\u0103ng c\u1ee7a c\u1ea3 hai bi\u1ebfn c\u1ed1 c\u00f9ng x\u1ea3y ra.\u00a0<\/i><\/p>\n<p>X\u00e1c su\u1ea5t c\u00f3 \u0111i\u1ec1u ki\u1ec7n c\u00f3 th\u1ec3 \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng \u0111\u1ec3 t\u00ednh x\u00e1c su\u1ea5t k\u1ebft h\u1ee3p, c\u00f4ng th\u1ee9c nh\u01b0 sau:<\/p>\n<p><b>P(X\u2229Y) = P(X|Y) * P(Y)\u00a0<\/b><\/p>\n<p>\u00c1p d\u1ee5ng c\u00f4ng th\u1ee9c n\u00e0y cho x\u00e1c su\u1ea5t r\u00fat \u0111\u01b0\u1ee3c l\u00e1 6 v\u00e0 \u0111\u1ecf c\u00f9ng m\u1ed9t l\u00fac s\u1ebd l\u00e0:  P(6\u2229\u0111\u1ecf) = P(6|\u0111\u1ecf) * P(\u0111\u1ecf)= 1\/13 * 26\/52 = 1\/13 * 1\/2 =1\/26<\/p>\n<p>(Theo <i>Investopedia<\/i>)<\/p>\n<\/p><\/div>\n","protected":false},"excerpt":{"rendered":"<div class=\"vnbcbc-sapo\" data-role=\"sapo\">\n                            X\u00e1c su\u1ea5t k\u1ebft h\u1ee3p (ti\u1ebfng Anh: Joint Probability) l\u00e0 m\u1ed9t th\u01b0\u1edbc \u0111o th\u1ed1ng k\u00ea t\u00ednh to\u00e1n kh\u1ea3 n\u0103ng hai bi\u1ebfn c\u1ed1 x\u1ea3y ra c\u00f9ng m\u1ed9t l\u00fac v\u00e0 t\u1ea1i c\u00f9ng m\u1ed9t th\u1eddi \u0111i\u1ec3m.\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\/25258"}],"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=25258"}],"version-history":[{"count":0,"href":"https:\/\/masterskills.org\/blog\/wp-json\/wp\/v2\/posts\/25258\/revisions"}],"wp:attachment":[{"href":"https:\/\/masterskills.org\/blog\/wp-json\/wp\/v2\/media?parent=25258"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/masterskills.org\/blog\/wp-json\/wp\/v2\/categories?post=25258"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/masterskills.org\/blog\/wp-json\/wp\/v2\/tags?post=25258"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}