{"id":5855,"date":"2021-12-20T18:57:25","date_gmt":"2021-12-20T10:57:25","guid":{"rendered":"http:\/\/43.154.99.198\/?p=5855"},"modified":"2022-11-01T20:42:31","modified_gmt":"2022-11-01T12:42:31","slug":"fundamentals-of-machine-learning-and-linear-models","status":"publish","type":"post","link":"https:\/\/www.wangonc.com\/index.php\/2021\/12\/20\/fundamentals-of-machine-learning-and-linear-models\/","title":{"rendered":"\u673a\u5668\u5b66\u4e60\u57fa\u7840\u4e0e\u7ebf\u6027\u6a21\u578b\uff08\u4e00\uff09"},"content":{"rendered":"<div class=\"pps-series-post-details pps-series-post-details-variant-classic pps-series-post-details-8136\" data-series-id=\"38\"><div class=\"pps-series-meta-content\"><div class=\"pps-series-meta-text\">This entry is \u7b2c 1 \u90e8\u5206\uff0c\u5171 3 in the series <a href=\"https:\/\/www.wangonc.com\/index.php\/series\/machine-learning\/\">\u673a\u5668\u5b66\u4e60<\/a><\/div><\/div><\/div><h2>1\u3001\u76d1\u7763\u5b66\u4e60\u4e0e\u65e0\u76d1\u7763\u5b66\u4e60<\/h2>\n<p><strong>\u76d1\u7763\u5b66\u4e60<\/strong>\uff1a\u6570\u636e\u96c6\u5e26\u6709\u6807\u7b7e\uff0c\u6839\u636e\u6570\u636e\u96c6\u5f97\u5230\u4e00\u4e2a\u56de\u5f52\u5e76\u5c06\u8f93\u5165\u6570\u636e\u5f97\u5230\u4e00\u4e2a\u552f\u4e00\u7ed3\u679c<\/p>\n<p>\u6570\u636e\u8fde\u7eed\u2014\u2014\u300b\u56de\u5f52\u95ee\u9898<\/p>\n<p>\u6570\u636e\u79bb\u6563\u2014\u2014\u300b\u5206\u7c7b\u95ee\u9898<\/p>\n<p><strong>\u65e0\u76d1\u7763\u95ee\u9898<\/strong>\uff1a\u6570\u636e\u96c6\u4e0d\u5e26\u6709\u6807\u7b7e\uff0c\u673a\u5668\u81ea\u5df1\u5c06\u6570\u636e\u96c6\u8fdb\u884c\u5206\u7c7b\uff08\u805a\u7c7b\u95ee\u9898\uff09<\/p>\n<h2>2\u3001\u7ebf\u6027\u6a21\u578b\u7684\u4ee3\u4ef7\u51fd\u6570<\/h2>\n<p><strong>\u6a21\u578b<\/strong>\uff1a\u57fa\u4e8e\u8f93\u5165\u6570\u636e\u96c6\u8ba1\u7b97\u51fa\u7684\u8f93\u51fa\u8868\u8fbe\u5f0f<\/p>\n<p><strong>\u8bad\u7ec3\u6a21\u578b<\/strong>\uff1a\u901a\u8fc7\u6570\u636e\u6765\u5bfb\u627e\u7279\u5b9a\u7684\u6a21\u578b\u53c2\u6570\u503c\uff0c\u4f7f\u6a21\u578b\u5728\u6570\u636e\u4e0a\u7684\u8bef\u5dee\u5c3d\u53ef\u80fd\u5c0f\u7684\u8fc7\u7a0b<\/p>\n<p><strong>\u8bad\u7ec3\u6570\u636e\u96c6<\/strong>\uff1a\u7528\u4e8e\u5bfb\u627e\u6a21\u578b\u53c2\u6570\u6765\u4f7f\u5f97\u771f\u5b9e\u503c\u4e0e\u9884\u6d4b\u503c\u8bef\u5dee\u6700\u5c0f\u7684\u6570\u636e\u96c6\u5408<\/p>\n<hr \/>\n<p>\u5bf9\u4e8e\u7ebf\u6027\u6a21\u578b\u7684\u56de\u5f52\u95ee\u9898\uff0c\u5176\u51fd\u6570\u672a\u786e\u5b9a\u4e4b\u524d\u5176\u51fd\u6570\u5982\u4e0b<\/p>\n<pre><code class=\"language-katex\">h_\\theta(x) = \\theta_0+\\theta_1x<\/code><\/pre>\n<p><strong>\u4ee3\u4ef7\u51fd\u6570<\/strong>\u662f\u4e3a\u4e86\u627e\u51fa\u8bef\u5dee\u5c3d\u53ef\u80fd\u5c0f\u7684\u53c2\u6570\u503c\uff0c\u5176\u51fd\u6570\u5982\u4e0b<\/p>\n<pre><code class=\"language-katex\">J(\\theta_0,\\theta_1) = \\frac{1}{2m}\\sum_{i=1}^{m} ( h_{\\theta}(x^ {(i)})-y^ {( i )} )^2<\/code><\/pre>\n<p>\u5176\u542b\u4e49\u5c31\u662f\u56de\u5f52\u4e4b\u524d\u4e0a\u4e0b\u70b9\u5230\u56de\u5f52\u76f4\u7ebf\u7684\u5e73\u5747\u8ddd\u79bb\u5c3d\u53ef\u80fd\u5c0f<\/p>\n<blockquote>\n<p>\u4e4b\u6240\u4ee5\u524d\u9762\u67091\/2\u662f\u56e0\u4e3a\u6c42\u5bfc\u540e\u65b9\u4fbf\u5904\u7406<\/p>\n<\/blockquote>\n<h2>3\u3001\u6c42\u51fa\u4ee3\u4ef7\u51fd\u6570\u6700\u5c0f\u503c\u7684\u7b97\u6cd5\u2014\u2014\u68af\u5ea6\u4e0b\u964d<\/h2>\n<p>\u68af\u5ea6\u4e0b\u964d\uff1a\u5728\u5404\u4e2a\u68af\u5ea6\uff08\u5bfc\u51fd\u6570\uff09\u5bfb\u627e\u4e0b\u964d\u901f\u5ea6\u6700\u5feb\u7684\u65b9\u5411<\/p>\n<p>\u68af\u5ea6\u7684\u610f\u4e49\u8868\u793a\u51fd\u6570\u5728\u67d0\u4e2a\u65b9\u5411\u4e0a\u53d8\u5316\u901f\u5ea6\u6700\u5feb<\/p>\n<p>\u03b1\u6210\u4e3a\u5b66\u4e60\u7387\uff0c\u5373\u6bcf\u4e00\u6b21\u8fed\u4ee3\u4e0b\u964d\u7684\u5e45\u5ea6<\/p>\n<p>\u5b66\u4e60\u7387\u8fc7\u5c0f\u53ef\u80fd\u5bfc\u81f4\u8fed\u4ee3\u6b21\u6570\u8fc7\u591a\uff0c\u5b66\u4e60\u7387\u8fc7\u5927\u53ef\u80fd\u5bfc\u81f4\u65e0\u6cd5\u627e\u5230\u4ee3\u4ef7\u51fd\u6570\u7684\u6700\u5c0f\u503c<\/p>\n<p>\u4e0b\u9762\u4e3a\u68af\u5ea6\u4e0b\u964d\u7b97\u6cd5\u7684\u57fa\u672c\u516c\u5f0f<\/p>\n<pre><code class=\"language-katex\">\\theta j:=\\theta _j-\\alpha \\frac {\\partial}{\\partial \\theta_j} J(\\theta_0,\\theta_1)<\/code><\/pre>\n<p>\u5176\u542b\u4e49\u4e3a\u6bcf\u6b21\u66f4\u65b0\u53c2\u6570\uff0c\u6839\u636e\u5176\uff08\u504f\uff09\u5012\u6570\uff08\u659c\u7387\u6216\u68af\u5ea6\uff09\u7684\u503c\u51b3\u5b9a\u5e94\u8be5\u4e0b\u964d\u7684\u65b9\u5411\uff0c\u6240\u4ee5\u4e3a\u53c2\u6570-\u5bfc\u6570\u503c<\/p>\n<p>\u5f53\u60c5\u51b5\u4e3a\u591a\u5143\u51fd\u6570\u65f6\uff0c\u591a\u4e2a\u53c2\u6570\u6240\u5bf9\u5e94\u7684\u591a\u4e2a\u504f\u5bfc\u6570\u9700\u8981\u540c\u65f6\u8fed\u4ee3<\/p>\n","protected":false},"excerpt":{"rendered":"<div class=\"pps-series-post-details pps-series-post-details-variant-classic pps-series-post-details-8136 pps-series-meta-excerpt\" data-series-id=\"38\"><div class=\"pps-series-meta-content\"><div class=\"pps-series-meta-text\">This entry is \u7b2c 1 \u90e8\u5206\uff0c\u5171 3 in the series <a href=\"https:\/\/www.wangonc.com\/index.php\/series\/machine-learning\/\">\u673a\u5668\u5b66\u4e60<\/a><\/div><\/div><\/div><p>1\u3001\u76d1\u7763\u5b66\u4e60\u4e0e\u65e0\u76d1\u7763\u5b66\u4e60 \u76d1\u7763\u5b66\u4e60\uff1a\u6570\u636e\u96c6\u5e26\u6709\u6807\u7b7e\uff0c\u6839\u636e\u6570\u636e\u96c6\u5f97\u5230\u4e00\u4e2a\u56de\u5f52\u5e76\u5c06\u8f93\u5165\u6570\u636e\u5f97\u5230\u4e00\u4e2a\u552f\u4e00\u7ed3\u679c \u6570\u636e\u8fde [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":5862,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[7,2],"tags":[29],"series":[38],"class_list":["post-5855","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-artificial-intelligence","category-study-notes","tag-machine-learning","series-machine-learning"],"_links":{"self":[{"href":"https:\/\/www.wangonc.com\/index.php\/wp-json\/wp\/v2\/posts\/5855","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.wangonc.com\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.wangonc.com\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.wangonc.com\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.wangonc.com\/index.php\/wp-json\/wp\/v2\/comments?post=5855"}],"version-history":[{"count":5,"href":"https:\/\/www.wangonc.com\/index.php\/wp-json\/wp\/v2\/posts\/5855\/revisions"}],"predecessor-version":[{"id":6671,"href":"https:\/\/www.wangonc.com\/index.php\/wp-json\/wp\/v2\/posts\/5855\/revisions\/6671"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.wangonc.com\/index.php\/wp-json\/wp\/v2\/media\/5862"}],"wp:attachment":[{"href":"https:\/\/www.wangonc.com\/index.php\/wp-json\/wp\/v2\/media?parent=5855"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.wangonc.com\/index.php\/wp-json\/wp\/v2\/categories?post=5855"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.wangonc.com\/index.php\/wp-json\/wp\/v2\/tags?post=5855"},{"taxonomy":"series","embeddable":true,"href":"https:\/\/www.wangonc.com\/index.php\/wp-json\/wp\/v2\/series?post=5855"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}