{"id":45037,"date":"2023-12-11T15:04:41","date_gmt":"2023-12-11T07:04:41","guid":{"rendered":"https:\/\/wx.kaifamiao.info\/?p=45037"},"modified":"2023-12-11T15:04:41","modified_gmt":"2023-12-11T07:04:41","slug":"xgboost%e5%8e%9f%e7%90%86%ef%bc%8c%e6%80%8e%e4%b9%88%e9%98%b2%e8%bf%87%e6%8b%9f%e5%90%88%ef%bc%9f-2","status":"publish","type":"post","link":"http:\/\/wx.kaifamiao.info\/index.php\/2023\/12\/11\/xgboost%e5%8e%9f%e7%90%86%ef%bc%8c%e6%80%8e%e4%b9%88%e9%98%b2%e8%bf%87%e6%8b%9f%e5%90%88%ef%bc%9f-2\/","title":{"rendered":"xgboost\u539f\u7406\uff0c\u600e\u4e48\u9632\u8fc7\u62df\u5408\uff1f"},"content":{"rendered":"

“`” \u53c2\u8003\u56de\u7b54\uff1a<\/p>\n

XGBoost\u662f\u4e00\u4e2a\u6811\u96c6\u6210\u6a21\u578b\uff0c\u5b83\u4f7f\u7528\u7684\u662fK\uff08\u6811\u7684\u603b\u6570\u4e3aK\uff09\u4e2a\u6811\u7684\u6bcf\u68f5\u6811\u5bf9\u6837\u672c\u7684\u9884\u6d4b\u503c\u7684\u548c\u4f5c\u4e3a\u8be5\u6837\u672c\u5728XGBoost\u7cfb\u7edf\u4e2d\u7684\u9884\u6d4b\uff0c\u5b9a\u4e49\u51fd\u6570\u5982\u4e0b\uff1a<\/p>\n

<img alt=""img"" referrerpolicy=""no-referrer"" src=""https:\/\/uploadfiles.nowcoder.com\/images\/20190315\/311436_1552654356997_C14022E909704D601526BE46C12F5B32""><\/p>\n

\u5bf9\u4e8e\u6240\u7ed9\u7684\u6570\u636e\u96c6\u6709n\u4e2a\u6837\u672c\uff0cm\u4e2a\u7279\u5f81\uff0c\u5b9a\u4e49\u4e3a\uff1a<\/p>\n

<img alt=""img"" referrerpolicy=""no-referrer"" src=""https:\/\/uploadfiles.nowcoder.com\/images\/20190315\/311436_1552654336100_D9D86CDDDFD56E5AC66FA7122337BB34""><\/p>\n

\u5176\u4e2dXi\u8868\u793a\u7b2ci\u4e2a\u6837\u672c\uff0cyi\u8868\u793a\u7b2ci\u4e2a\u6837\u672c\u7684\u7c7b\u522b\u6807\u7b7e\u3002CART\u6811\u7684\u7a7a\u95f4\u4e3aF\uff0c\u5982\u4e0b\uff1a<\/p>\n

<img alt=""img"" referrerpolicy=""no-referrer"" src=""https:\/\/uploadfiles.nowcoder.com\/images\/20190315\/311436_1552654318424_C601668340D98EE27A9FD52BE0B41E17""><\/p>\n

\u5176\u4e2dq\u8868\u793a\u6bcf\u68f5\u6811\u7684\u7ed3\u6784\u6620\u5c04\u6bcf\u4e2a\u6837\u672c\u5230\u76f8\u5e94\u7684\u53f6\u8282\u70b9\u7684\u5206\u6570\uff0c\u5373q\u8868\u793a\u6811\u7684\u6a21\u578b\uff0c\u8f93\u5165\u4e00\u4e2a\u6837\u672c\uff0c\u6839\u636e\u6a21\u578b\u5c06\u6837\u672c\u6620\u5c04\u5230\u53f6\u8282\u70b9\u8f93\u51fa\u9884\u6d4b\u7684\u5206\u6570\uff1bWq(x)\u8868\u793a\u6811q\u7684\u6240\u6709\u53f6\u8282\u70b9\u7684\u5206\u6570\u7ec4\u6210\u96c6\u5408\uff1bT\u662f\u6811q\u7684\u53f6\u8282\u70b9\u6570\u91cf\u3002<\/p>\n

\u6240\u4ee5\uff0c\u7531\uff081\uff09\u5f0f\u53ef\u4ee5\u770b\u51fa\uff0cXGBoost\u7684\u9884\u6d4b\u503c\u4e3a\u6bcf\u68f5\u6811\u7684\u9884\u6d4b\u503c\u4e4b\u548c\uff0c\u5373\u6bcf\u68f5\u6811\u76f8\u5e94\u7684\u53f6\u8282\u70b9\u7684\u5f97\u5206\u4e4b\u548c\uff08Wi\u7684\u548c\uff0cWi\u8868\u793a\u7b2ci\u4e2a\u53f6\u8282\u70b9\u7684\u5f97\u5206\uff09\u3002<\/p>\n

\u6211\u4eec\u7684\u76ee\u6807\u5c31\u662f\u5b66\u4e60\u8fd9\u6837\u7684K\u4e2a\u6811\u6a21\u578bf(x).\u3002\u4e3a\u4e86\u5b66\u4e60\u6a21\u578bf(x)\uff0c\u6211\u4eec\u5b9a\u4e49\u4e0b\u9762\u7684\u76ee\u6807\u51fd\u6570\uff1a<\/p>\n

<img alt=""img"" referrerpolicy=""no-referrer"" src=""https:\/\/uploadfiles.nowcoder.com\/images\/20190315\/311436_1552654218581_DA95B0A56591F1C9282B2990A1722F21""><\/p>\n

<img alt=""img"" referrerpolicy=""no-referrer"" src=""https:\/\/uploadfiles.nowcoder.com\/images\/20190315\/311436_1552654229021_2B788F295514EACE36B431E4834D5F61""><\/p>\n

\u5176\u4e2d\uff0c\uff082\uff09\u5f0f\u53f3\u8fb9\u7b2c\u4e00\u9879\u4e3a\u635f\u5931\u51fd\u6570\u9879\uff0c\u5373\u8bad\u7ec3\u8bef\u5dee\uff0c\u662f\u4e00\u4e2a\u53ef\u5fae\u7684\u51f8\u51fd\u6570\uff08\u6bd4\u5982\u7528\u4e8e\u56de\u5f52\u7684\u5747\u65b9\u8bef\u5dee\u548c\u7528\u4e8e\u5206\u7c7b\u7684Logistic\u8bef\u5dee\u51fd\u6570\u7b49\uff09\uff0c\u7b2c\u4e8c\u9879\u4e3a\u6b63\u5219\u5316\u9879\uff0c\u5373\u6bcf\u68f5\u6811\u7684\u590d\u6742\u5ea6\u4e4b\u548c\uff0c\u76ee\u7684\u662f\u63a7\u5236\u6a21\u578b\u7684\u590d\u6742\u5ea6\uff0c\u9632\u6b62\u8fc7\u62df\u5408\u3002\u6211\u4eec\u7684\u76ee\u6807\u662f\u5728L(\u03c6)\u53d6\u5f97\u6700\u5c0f\u5316\u65f6\u5f97\u51fa\u5bf9\u5e94\u7684\u6a21\u578bf(x)\u3002<\/p>\n

\u7531\u4e8eXGBoost\u6a21\u578b\u4e2d\u7684\u4f18\u5316\u53c2\u6570\u662f\u6a21\u578bf(x)\uff0c\u4e0d\u662f\u4e00\u4e2a\u5177\u4f53\u7684\u503c\uff0c\u6240\u4ee5\u4e0d\u80fd\u7528\u4f20\u7edf\u7684\u4f18\u5316\u65b9\u6cd5\u5728\u6b27\u5f0f\u7a7a\u95f4\u4e2d\u8fdb\u884c\u4f18\u5316\uff0c\u800c\u662f\u91c7\u7528additive training\u7684\u65b9\u5f0f\u53bb\u5b66\u4e60\u6a21\u578b\u3002\u6bcf\u4e00\u6b21\u4fdd\u7559\u539f\u6765\u7684\u6a21\u578b\u4e0d\u53d8\uff0c\u52a0\u5165\u4e00\u4e2a\u65b0\u7684\u51fd\u6570f\u5230\u6a21\u578b\u4e2d\uff0c\u5982\u4e0b\uff1a<\/p>\n

<img alt=""img"" referrerpolicy=""no-referrer"" src=""https:\/\/uploadfiles.nowcoder.com\/images\/20190315\/311436_1552654275454_6D0F9075126C579116BABEBA0744F1BD""><\/p>\n

\u9884\u6d4b\u503c\u5728\u6bcf\u4e00\u6b21\u8fed\u4ee3\u4e2d\u52a0\u5165\u4e00\u4e2a\u65b0\u7684\u51fd\u6570f\u76ee\u7684\u662f\u4f7f\u76ee\u6807\u51fd\u6570\u5c3d\u91cf\u6700\u5927\u5730\u964d\u4f4e\u3002<\/p>\n

\u56e0\u4e3a\u6211\u4eec\u7684\u76ee\u6807\u662f\u6700\u5c0f\u5316L(\u03c6)\u65f6\u5f97\u5230\u6a21\u578bf(x)\uff0c\u4f46\u662fL(\u03c6)\u4e2d\u5e76\u6ca1\u6709\u53c2\u6570f(x)\uff0c\u6240\u4ee5\uff0c\u6211\u4eec\u5c06\u4e0a\u56fe\u4e2d\u7684\u6700\u540e\u4e00\u5f0f\u4ee3\u5165L(\u03c6)\u4e2d\u53ef\u5f97\u5230\u5982\u4e0b\u5f0f\u5b50\uff1a<\/p>\n

<img alt=""img"" referrerpolicy=""no-referrer"" src=""https:\/\/uploadfiles.nowcoder.com\/images\/20190315\/311436_1552654545445_AA41B6FD9D442CD3F1BD7E58A9FADF6E""><\/p>\n

\u5bf9\u4e8e\u5e73\u65b9\u8bef\u5dee\uff08\u7528\u4e8e\u56de\u5f52\uff09\u6765\u8bf4\uff083\uff09\u5f0f\u8f6c\u6362\u6210\u5982\u4e0b\u5f62\u5f0f\uff1a<\/p>\n

<img alt=""img"" referrerpolicy=""no-referrer"" src=""https:\/\/uploadfiles.nowcoder.com\/images\/20190315\/311436_1552654531702_8C8E87DEB95D4EE1251D4C1727E6E338""><\/p>\n

\u5bf9\u4e8e\u4e0d\u662f\u5e73\u65b9\u8bef\u5dee\u7684\u60c5\u51b5\u4e0b\uff0c\u4e00\u822c\u4f1a\u91c7\u7528\u6cf0\u52d2\u5c55\u5f00\u5f0f\u6765\u5b9a\u4e49\u4e00\u4e2a\u8fd1\u4f3c\u7684\u76ee\u6807\u51fd\u6570\uff0c\u4ee5\u65b9\u4fbf\u6211\u4eec\u7684\u8fdb\u4e00\u6b65\u8ba1\u7b97\u3002<\/p>\n

\u6839\u636e\u5982\u4e0b\u7684\u6cf0\u52d2\u5c55\u5f00\u5f0f\uff0c\u79fb\u9664\u9ad8\u9636\u65e0\u7a77\u5c0f\u9879\uff0c\u5f97\uff1a<\/p>\n

<img alt=""img"" referrerpolicy=""no-referrer"" src=""https:\/\/uploadfiles.nowcoder.com\/images\/20190315\/311436_1552654515691_247EF8F9FB11113DF4095C2AF693DB7E""><\/p>\n

<img alt=""img"" referrerpolicy=""no-referrer"" src=""https:\/\/uploadfiles.nowcoder.com\/images\/20190315\/311436_1552654498504_E74F441D04F2B635B26975278595311D""><\/p>\n

\uff083\uff09\u5f0f\u7b49\u4ef7\u4e8e\u4e0b\u9762\u7684\u5f0f\u5b50\uff1a<\/p>\n

<img alt=""img"" referrerpolicy=""no-referrer"" src=""https:\/\/uploadfiles.nowcoder.com\/images\/20190315\/311436_1552654483338_BA4FD8E055E6CC4DDBA93F9774B548A4""><\/p>\n

\u7531\u4e8e\u6211\u4eec\u7684\u76ee\u6807\u662f\u6c42L(\u03c6)\u6700\u5c0f\u5316\u65f6\u7684\u6a21\u578bf(x)\uff08\u4e5f\u662f\u53d8\u91cf\uff09\uff0c\u5f53\u79fb\u9664\u5e38\u6570\u9879\u65f6\u6a21\u578b\u7684\u6700\u5c0f\u503c\u53d8\u5316\uff0c\u4f46\u662f\u53d6\u6700\u5c0f\u503c\u7684\u53d8\u91cf\u4e0d\u53d8\uff08\u6bd4\u5982\uff1ay=x^2+C\uff0c\u65e0\u8bbaC\u53bb\u4f55\u503c\uff0cx\u90fd\u57280\u5904\u53d6\u6700\u5c0f\u503c\uff09\u3002\u6240\u4ee5\uff0c\u4e3a\u4e86\u7b80\u5316\u8ba1\u7b97\uff0c\u6211\u4eec\u79fb\u9664\u5e38\u6570\u9879\uff0c\u5f97\u5230\u5982\u4e0b\u7684\u76ee\u6807\u51fd\u6570\uff1a<\/p>\n

<img alt=""img"" referrerpolicy=""no-referrer"" src=""https:\/\/uploadfiles.nowcoder.com\/images\/20190315\/311436_1552654469172_F531D4625946FBDE30017CF92A508DD8""><\/p>\n

\u5b9a\u4e49<img alt=""img"" referrerpolicy=""no-referrer"" src=""https:\/\/uploadfiles.nowcoder.com\/images\/20190315\/311436_1552654451035_2DB3B28ECCF5B5A190EDE8F315E673D9""> \u4e3a\u53f6\u8282\u70b9j\u7684\u5b9e\u4f8b\uff0c\u91cd\u5199\uff084\uff09\u5f0f\uff0c\u5c06\u5173\u4e8e\u6811\u6a21\u578b\u7684\u8fed\u4ee3\u8f6c\u6362\u4e3a\u5173\u4e8e\u6811\u7684\u53f6\u5b50\u8282\u70b9\u7684\u8fed\u4ee3\uff0c\u5f97\u5230\u5982\u4e0b\u8fc7\u7a0b\uff1a<\/p>\n

<img alt=""img"" referrerpolicy=""no-referrer"" src=""https:\/\/uploadfiles.nowcoder.com\/images\/20190315\/311436_1552654624457_DADDD0F0171B5F2ADFDC767043C36B94""><\/p>\n

\u6b64\u65f6\u6211\u4eec\u7684\u76ee\u6807\u662f\u6c42\u6bcf\u68f5\u6811\u7684\u53f6\u8282\u70b9j\u7684\u5206\u6570Wj\uff0c\u6c42\u51faWj\u540e\uff0c\u5c06\u6bcf\u68f5\u6811\u7684Wj\u76f8\u52a0\uff0c\u5373\u53ef\u5f97\u5230\u6700\u7ec8\u7684\u9884\u6d4b\u7684\u5206\u6570\u3002\u800c\u8981\u60f3\u5f97\u5230\u6700\u4f18\u7684Wj\u7684\u503c\uff0c\u5373\u6700\u5c0f\u5316\u6211\u4eec\u7684\u76ee\u6807\u51fd\u6570\uff0c\u6240\u4ee5\u4e0a\u5f0f\u5bf9Wj\u6c42\u504f\u5bfc\uff0c\u5e76\u4ee4\u504f\u5bfc\u6570\u4e3a0\uff0c\u7b97\u51fa\u6b64\u65f6\u7684W*j\u4e3a\uff1a<\/p>\n

<img alt=""img"" referrerpolicy=""no-referrer"" src=""https:\/\/uploadfiles.nowcoder.com\/images\/20190315\/311436_1552654685059_2842BAC8D592204451186D4BB0281E21""><\/p>\n

<img alt=""img"" referrerpolicy=""no-referrer"" src=""https:\/\/uploadfiles.nowcoder.com\/images\/20190315\/311436_1552654671657_8915C25DF2078E084BCD9002BE3FADB9""><\/p>\n

\u5c06W*j\u4ee3\u5165\u539f\u5f0f\u5f97\uff1a<\/p>\n

<img alt=""img"" referrerpolicy=""no-referrer"" src=""https:\/\/uploadfiles.nowcoder.com\/images\/20190315\/311436_1552654657763_0C64F280CB46F2223B5E422CD44DDDCA""><\/p>\n

\u65b9\u7a0b\uff085\uff09\u53ef\u4ee5\u7528\u4f5c\u5f97\u5206(score)\u51fd\u6570\u6765\u6d4b\u91cf\u6811\u7ed3\u6784q\u7684\u8d28\u91cf\u3002\u8be5\u5f97\u5206\u7c7b\u4f3c\u4e8e\u8bc4\u4f30\u51b3\u7b56\u6811\u7684\u4e0d\u7eaf\u5ea6\u5f97\u5206\uff0c\u9664\u4e86\u5b83\u662f\u9488\u5bf9\u66f4\u5e7f\u6cdb\u7684\u76ee\u6807\u51fd\u6570\u5f97\u51fa\u7684\u3002<\/p>\n

\u5728xgboost\u8c03\u4e2d\uff0c\u4e00\u822c\u6709\u4e24\u79cd\u65b9\u5f0f\u7528\u4e8e\u63a7\u5236\u8fc7\u62df\u5408\uff1a1\uff09\u76f4\u63a5\u63a7\u5236\u53c2\u6570\u7684\u590d\u6742\u5ea6\uff1a\u5305\u62ecmax_depth min_child_weight gamma\uff1b2\uff09add randomness\u6765\u4f7f\u5f97\u5bf9\u8bad\u7ec3\u5bf9\u566a\u58f0\u9c81\u68d2\u3002\u5305\u62ecsubsample colsample_bytree\uff0c\u6216\u8005\u4e5f\u53ef\u4ee5\u51cf\u5c0f\u6b65\u957f eta\uff0c\u4f46\u662f\u9700\u8981\u589e\u52a0num_round\uff0c\u6765\u5e73\u8861\u6b65\u957f\u56e0\u5b50\u7684\u51cf\u5c0f\u3002<\/p>\n

<pre><code> "“`
\n<\/code><\/pre>\n","protected":false},"excerpt":{"rendered":"

“`” \u53c2\u8003\u56de\u7b54\uff1a XGBoost\u662f\u4e00\u4e2a\u6811\u96c6\u6210\u6a21\u578b\uff0c\u5b83\u4f7f\u7528\u7684\u662fK\uff08\u6811\u7684\u603b\u6570\u4e3aK\uff09\u4e2a\u6811\u7684 […]<\/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-45037","post","type-post","status-publish","format-standard","hentry","category-c"],"_links":{"self":[{"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/posts\/45037","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=45037"}],"version-history":[{"count":1,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/posts\/45037\/revisions"}],"predecessor-version":[{"id":45038,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/posts\/45037\/revisions\/45038"}],"wp:attachment":[{"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/media?parent=45037"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/categories?post=45037"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/wx.kaifamiao.info\/index.php\/wp-json\/wp\/v2\/tags?post=45037"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}