“`” \u53c2\u8003\u56de\u7b54\uff1a<\/p>\n
GBDT(Gradient Boosting Decision Tree) \u53c8\u53eb MART\uff08Multiple Additive Regression Tree)\uff0c\u662f\u4e00\u79cd\u7528\u4e8e\u56de\u5f52\u7684\u673a\u5668\u5b66\u4e60\u7b97\u6cd5\uff0c\u8be5\u7b97\u6cd5\u7531\u591a\u68f5\u56de\u5f52\u51b3\u7b56\u6811\u7ec4\u6210\uff0c\u6240\u6709\u6811\u7684\u7ed3\u8bba\u7d2f\u52a0\u8d77\u6765\u505a\u6700\u7ec8\u7b54\u6848\u3002\u5f53\u628a\u76ee\u6807\u51fd\u6570\u505a\u53d8\u6362\u540e\uff0c\u8be5\u7b97\u6cd5\u4ea6\u53ef\u7528\u4e8e\u5206\u7c7b\u6216\u6392\u5e8f\u3002<\/p>\n
1\uff09\u660e\u786e\u635f\u5931\u51fd\u6570\u662f\u8bef\u5dee\u6700\u5c0f<\/p>\n
<img alt=""img"" referrerpolicy=""no-referrer"" src=""https:\/\/uploadfiles.nowcoder.com\/images\/20190315\/311436_1552653249291_74EAF19C5E1F40445C0BA04B53091779""><\/p>\n
2\uff09\u6784\u5efa\u7b2c\u4e00\u68f5\u56de\u5f52\u6811<\/p>\n
<img alt=""img"" referrerpolicy=""no-referrer"" src=""https:\/\/uploadfiles.nowcoder.com\/images\/20190315\/311436_1552653312755_29BD1A1D29B61907B572ECB1245CB8D0""><\/p>\n
3\uff09\u5b66\u4e60\u591a\u68f5\u56de\u5f52\u6811<\/p>\n
<img alt=""img"" referrerpolicy=""no-referrer"" src=""https:\/\/uploadfiles.nowcoder.com\/images\/20190315\/311436_1552653326719_BABAB26F646138D383BFC3785E50B286""><\/p>\n
\u8fed\u4ee3\uff1a\u8ba1\u7b97\u68af\u5ea6\/\u6b8b\u5deegm(\u5982\u679c\u662f\u5747\u65b9\u8bef\u5dee\u4e3a\u635f\u5931\u51fd\u6570\u5373\u4e3a\u6b8b\u5dee)<\/p>\n
\u6b65\u957f\/\u7f29\u653e\u56e0\u5b50p,\u7528 a single Newton-Raphson step \u53bb\u8fd1\u4f3c\u6c42\u89e3\u4e0b\u964d\u65b9\u5411\u6b65\u957f,\u901a\u5e38\u7684\u5b9e\u73b0\u4e2d Step3 \u88ab\u7701\u7565,\u91c7\u7528 shrinkage \u7684\u7b56\u7565\u901a\u8fc7\u53c2\u6570\u8bbe\u7f6e\u6b65\u957f,\u907f\u514d\u8fc7\u62df\u5408<\/p>\n
\u7b2cm\u68f5\u6811fm=p*gm<\/p>\n
\u6a21\u578bFm=Fm-1+p*gm<\/p>\n
4\uff09F(x)\u7b49\u4e8e\u6240\u6709\u6811\u7ed3\u679c\u7d2f\u52a0<\/p>\n
<img alt=""img"" referrerpolicy=""no-referrer"" src=""https:\/\/uploadfiles.nowcoder.com\/images\/20190315\/311436_1552653366801_1108183D2BEB2A3E02F8ABF96E7F2AD6""><\/p>\n
<pre><code> "“`
\n<\/code><\/pre>\n","protected":false},"excerpt":{"rendered":"
“`” \u53c2\u8003\u56de\u7b54\uff1a GBDT(Gradient Boosting Decision T […]<\/p>\n","protected":false},"author":7,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[101],"tags":[],"class_list":["post-45027","post","type-post","status-publish","format-standard","hentry","category-c"],"_links":{"self":[{"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/posts\/45027","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/users\/7"}],"replies":[{"embeddable":true,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/comments?post=45027"}],"version-history":[{"count":1,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/posts\/45027\/revisions"}],"predecessor-version":[{"id":45028,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/posts\/45027\/revisions\/45028"}],"wp:attachment":[{"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/media?parent=45027"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/categories?post=45027"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/tags?post=45027"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}