{"id":620,"date":"2023-08-09T18:43:55","date_gmt":"2023-08-09T10:43:55","guid":{"rendered":"https:\/\/blog.cirno.fun\/?p=620"},"modified":"2025-03-18T22:43:45","modified_gmt":"2025-03-18T14:43:45","slug":"chap12-k-means%e8%81%9a%e7%b1%bb","status":"publish","type":"post","link":"https:\/\/blog.sssn.tech\/?p=620","title":{"rendered":"[Chap12]-K-means\u805a\u7c7b"},"content":{"rendered":"<h2>\u65e0\u76d1\u7763\u5b66\u4e60<\/h2>\n<p>\u4ece\u8fd9\u8282\u5f00\u59cb, \u6211\u4eec\u5f00\u59cb\u4ecb\u7ecd\u65e0\u76d1\u7763\u5b66\u4e60\u7b97\u6cd5, \u5373, \u8ba9\u8ba1\u7b97\u673a\u5b66\u4e60\u65e0\u6807\u7b7e\u7684\u6570\u636e, \u800c\u4e0d\u662f\u6b64\u524d\u6709\u6807\u7b7e\u7684<\/p>\n<p>\u65e0\u76d1\u7763\u5b66\u4e60\u7684\u6570\u636e\u770b\u8d77\u6765\u662f\u8fd9\u6837\u7684<\/p>\n<p><img decoding=\"async\" src=\"https:\/\/blog.sssn.tech\/wp-content\/uploads\/2023\/08\/image-1691576271621.png\" alt=\"file\" \/><\/p>\n<p>\u76f8\u6bd4\u4e8e\u4e4b\u524d\u7684\u6570\u636e\u5c11\u4e86\u6807\u7b7e(y, \u70b9\u7684\u5f62\u72b6, \u53c9\u6216\u8005\u5708), \u6211\u4eec\u9700\u8981\u7b97\u6cd5\u6765\u544a\u8bc9\u6211\u4eec\u6570\u636e\u7684\u7ed3\u6784<\/p>\n<p>\u56fe\u4e0a\u6570\u636e\u770b\u8d77\u6765\u53ef\u4ee5\u5206\u4e3a\u4e24\u4e2a\u5206\u5f00\u7684\u70b9\u96c6, \u6216\u8005\u8bf4<strong>\u7c07(Cluster)<\/strong>, \u4e00\u4e2a\u80fd\u627e\u5230\u8fd9\u4e24\u4e2a\u70b9\u96c6\u7684\u7b97\u6cd5\u5c31\u79f0\u4f5c\u805a\u7c7b\u7b97\u6cd5<\/p>\n<p><strong>K\u5747\u503c(Kmeans)\u805a\u7c7b<\/strong>\u7b97\u6cd5\u662f\u65e0\u76d1\u7763\u5b66\u4e60\u7684\u4e00\u4e2a\u5178\u578b\u4f8b\u5b50<\/p>\n<p>\u805a\u7c7b\u7b97\u6cd5\u6709\u5f88\u591a\u7684\u5e94\u7528\u573a\u666f, \u6bd4\u5982\u7ed9\u51fa\u5927\u91cf\u5ba2\u6237\u7684\u884c\u4e3a\u4fe1\u606f, \u505a\u51fa\u5206\u7c7b\u4ee5\u4fbf\u5236\u5b9a\u4e0d\u540c\u9500\u552e\u7b56\u7565; \u53c8\u5982\u5206\u6790\u5929\u4f53\u7cfb\u7edf, \u7b49\u7b49<\/p>\n<p><img decoding=\"async\" src=\"https:\/\/blog.sssn.tech\/wp-content\/uploads\/2023\/08\/image-1691576781316.png\" alt=\"file\" \/><\/p>\n<h2>K-means\u7b97\u6cd5\u7684\u601d\u60f3<\/h2>\n<p>Kmeans\u662f\u4e00\u4e2a\u8fed\u4ee3\u7b97\u6cd5, \u5047\u8bbe\u6211\u4eec\u73b0\u5728\u8981\u628a\u6570\u636e\u5206\u4e3aK\u4e2a\u7ec4(K\u7684\u9009\u62e9\u65b9\u6cd5\u540e\u9762\u4f1a\u8bb2\u5230), \u6bd4\u5982\u4e0b\u56fe\u4e2d, \u6211\u4eec\u5c06\u9009\u62e9K=3<\/p>\n<p><img decoding=\"async\" src=\"https:\/\/blog.sssn.tech\/wp-content\/uploads\/2023\/08\/image-1691576930001.png\" alt=\"file\" \/><\/p>\n<ul>\n<li>\u9009\u62e9K\u4e2a\u968f\u673a\u7684\u70b9, \u79f0\u4e3a<strong>\u805a\u7c7b\u4e2d\u5fc3(Cluster centroids)<\/strong><\/li>\n<li>\u5bf9\u4e8e\u6570\u636e\u96c6\u4e2d\u7684\u6bcf\u4e00\u4e2a\u6570\u636e, \u9009\u62e9\u5176\u8ddd\u79bb\u6700\u8fd1\u7684\u805a\u7c7b\u4e2d\u5fc3\u4ee3\u8868\u7684\u7c7b\u522b<\/li>\n<li>\u5bf9\u4e8e\u6bcf\u4e00\u4e2a\u805a\u7c7b\u4e2d\u5fc3, \u8ba1\u7b97\u6240\u5c5e\u5176\u7684\u70b9\u7684\u5750\u6807\u5e73\u5747\u503c, \u7136\u540e\u5c06\u4e2d\u5fc3\u79fb\u52a8\u5230\u8be5\u4f4d\u7f6e<\/li>\n<li>\u91cd\u590d\u4e0a\u9762\u4e24\u6b65\u76f4\u5230\u4e2d\u5fc3\u4e0d\u518d\u53d8\u5316<\/li>\n<\/ul>\n<p>\u4e0b\u9762\u662f\u4e00\u4e2a\u805a\u7c7b\u793a\u4f8b:<\/p>\n<p><img decoding=\"async\" src=\"https:\/\/blog.sssn.tech\/wp-content\/uploads\/2023\/08\/image-1691577108226.png\" alt=\"file\" \/><\/p>\n<p><img decoding=\"async\" src=\"https:\/\/blog.sssn.tech\/wp-content\/uploads\/2023\/08\/image-1691577120799.png\" alt=\"file\" \/><\/p>\n<p>\u968f\u7740\u8fed\u4ee3, \u805a\u7c7b\u4e2d\u5fc3\u4f1a\u6e10\u6e10\u8d70\u5230\u7c7b\u522b\u7684\u4e2d\u5fc3<\/p>\n<p><img decoding=\"async\" src=\"https:\/\/blog.sssn.tech\/wp-content\/uploads\/2023\/08\/image-1691577183653.png\" alt=\"file\" \/><\/p>\n<p>\u5373\u4f7f\u6570\u636e\u6ca1\u6709\u660e\u663e\u533a\u5206\u7684\u65f6\u5019, Kmeans\u4e5f\u80fd\u5c06\u4e4b\u5206\u4e3a\u4e0d\u540c\u7684\u7ec4, \u4e0b\u56fe\u6240\u793a\u7684\u6570\u636e\u5305\u542b\u8eab\u9ad8\u548c\u4f53\u91cd, \u4ee5\u53caKmeans\u5bf9\u6570\u636e\u7684\u5206\u7c7b, \u7528\u4ee5\u5e2e\u52a9\u786e\u5b9a\u886c\u886b\u5c3a\u5bf8<\/p>\n<p><img decoding=\"async\" src=\"https:\/\/blog.sssn.tech\/wp-content\/uploads\/2023\/08\/image-1691577274430.png\" alt=\"file\" \/><\/p>\n<h2>\u4f18\u5316\u76ee\u6807<\/h2>\n<p>Kmeans\u9700\u8981\u6700\u5c0f\u5316\u7684\u76ee\u6807, \u5373\u662f\u6240\u6709\u6570\u636e\u70b9\u548c\u5176\u6240\u5173\u8054\u7684\u805a\u7c7b\u4e2d\u5fc3\u7684\u8ddd\u79bb\u4e4b\u548c, \u56e0\u6b64Kmeans\u7684\u4ee3\u4ef7\u51fd\u6570(\u53c8\u79f0<strong>\u7578\u53d8\u51fd\u6570, Distortion function<\/strong>)\u4e3a<\/p>\n<p><img decoding=\"async\" src=\"https:\/\/blog.sssn.tech\/wp-content\/uploads\/2023\/08\/image-1691577590651.png\" alt=\"file\" \/><\/p>\n<p>\u5176\u4e2dmui\u4ee3\u8868\u4e0ex\u6700\u8fd1\u7684\u805a\u7c7b\u4e2d\u5fc3<\/p>\n<p>\u56de\u987e\u521a\u521a\u7ed9\u51fa\u7684\u8fed\u4ee3\u8fc7\u7a0b<\/p>\n<p><img decoding=\"async\" src=\"https:\/\/blog.sssn.tech\/wp-content\/uploads\/2023\/08\/image-1691577183653.png\" alt=\"file\" \/><\/p>\n<p>\u7b2c\u4e00\u4e2a\u5faa\u73af\u662f\u7528\u4e8e\u51cf\u5c11ci\u5f15\u8d77\u7684\u4ee3\u4ef7, \u7b2c\u4e8c\u4e2a\u51cf\u5c11mui_i\u5f15\u8d77\u7684\u4ee3\u4ef7, \u6bcf\u4e00\u6b21\u8fed\u4ee3\u90fd\u5728\u51cf\u5c0f\u4ee3\u4ef7\u51fd\u6570<\/p>\n<h2>\u968f\u673a\u521d\u59cb\u5316<\/h2>\n<p>Kmeans\u6709\u4e00\u4e2a\u95ee\u9898: \u7b97\u6cd5\u6709\u53ef\u80fd\u4f1a\u505c\u7559\u5728\u4e00\u4e2a\u5c40\u90e8\u7684\u6700\u5c0f\u503c, \u8fd9\u53d6\u51b3\u4e8e\u521d\u59cb\u5316\u805a\u7c7b\u4e2d\u5fc3\u7684\u60c5\u51b5<\/p>\n<p><img decoding=\"async\" src=\"https:\/\/blog.sssn.tech\/wp-content\/uploads\/2023\/08\/image-1691577772156.png\" alt=\"file\" \/><\/p>\n<p>\u4e0a\u56fe\u5217\u51fa\u4e86\u51e0\u79cd\u53ef\u80fd\u7684\u6536\u655b\u7ed3\u679c, \u53ea\u6709\u4e00\u79cd\u662f\u6211\u4eec\u6bd4\u8f83\u6ee1\u610f\u7684<\/p>\n<p>\u4e3a\u4e86\u89e3\u51b3\u8fd9\u4e2a\u95ee\u9898, \u901a\u5e38\u9700\u8981\u591a\u6b21\u8fd0\u884cKmeans, \u6bcf\u4e00\u6b21\u90fd\u91cd\u65b0\u968f\u673a\u521d\u59cb\u5316, \u7136\u540e\u518d\u6bd4\u8f83\u591a\u6b21\u8fd0\u884c\u7684\u7ed3\u679c, \u9009\u62e9\u4ee3\u4ef7\u51fd\u6570\u6700\u5c0f\u7684\u7ed3\u679c, \u8fd9\u79cd\u505a\u6cd5\u518dK\u8f83\u5c0f\u65f6(2-10)\u662f\u53ef\u884c\u7684, \u5982\u679cK\u8fc7\u5927, \u53ef\u80fd\u4e0d\u4f1a\u6709\u660e\u663e\u7684\u6539\u5584<\/p>\n<h2>\u9009\u62e9\u805a\u7c7b\u6570(K)<\/h2>\n<p>\u4e8b\u5b9e\u4e0a\u6ca1\u6709\u975e\u5e38\u597d\u7684\u9009\u62e9\u805a\u7c7b\u6570\u7684\u65b9\u6cd5, \u901a\u5e38\u662f\u6839\u636e\u4e0d\u540c\u7684\u95ee\u9898\u8fdb\u884c\u4eba\u5de5\u9009\u62e9<\/p>\n<p>\u6bd4\u5982\u518d\u886c\u886b\u5206\u7c7b\u4f8b\u5b50\u4e2d, \u5982\u679c\u6211\u4eec\u51b3\u5b9a\u5236\u9020\u4e09\u4e2a\u5c3a\u5bf8SML, \u5219\u5c31\u5e94\u5f53\u628a\u5ba2\u6237\u5206\u4e3a\u4e09\u7c7b, \u53c8\u6bd4\u5982\u8981\u5236\u9020\u4e94\u4e2a\u5c3a\u5bf8, \u591a\u4e86XS\u548cXL, \u5c31\u5206\u4e3a\u4e94\u7c7b<\/p>\n<p>\u5bf9\u4e8e\u4e0d\u660e\u786e\u8981\u9009\u62e9\u805a\u7c7b\u6570\u7684\u60c5\u51b5, \u8fd9\u91cc\u6709\u4e00\u4e2a<strong>\u8098\u90e8\u6cd5\u5219<\/strong>\u53ef\u4ee5\u7528\u5230<\/p>\n<p>\u6211\u4eec\u6539\u53d8K\u503c, \u5217\u51fa\u5176\u5bf9\u4ee3\u4ef7\u51fd\u6570J\u7684\u56fe\u50cf, \u89c2\u5bdf\u5de6\u56fe<\/p>\n<p><img decoding=\"async\" src=\"https:\/\/blog.sssn.tech\/wp-content\/uploads\/2023\/08\/image-1691578325303.png\" alt=\"file\" \/><\/p>\n<p>\u5728K=3\u65f6, \u6709\u4e00\u4e2a\u6bd4\u8f83\u660e\u663e\u7684\u62d0\u70b9, \u597d\u50cf\u8098\u5173\u8282, \u8fd9\u8868\u660e\u4f7f\u7528K=3\u662f\u6bd4\u8f83\u5408\u9002\u7684<\/p>\n<p>\u5f53\u7136\u5728\u5b9e\u9645\u95ee\u9898\u4e2d, \u4e0d\u4f1a\u6c38\u8fdc\u90fd\u6709\u8fd9\u4e48\u7406\u60f3\u7684\u8098\u90e8\u53ef\u4f9b\u9009\u62e9, \u65f6\u5e38\u9047\u5230\u53f3\u56fe\u8fd9\u6837J\u5747\u5300\u4e0b\u964d\u7684\u60c5\u51b5, \u8fd9\u65f6\u8fd8\u662f\u9700\u8981\u6839\u636e\u5b9e\u9645\u9700\u8981\u6765\u51b3\u5b9aK\u7684\u503c<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u65e0\u76d1\u7763\u5b66\u4e60 \u4ece\u8fd9\u8282\u5f00\u59cb, \u6211\u4eec\u5f00\u59cb\u4ecb\u7ecd\u65e0\u76d1\u7763\u5b66\u4e60\u7b97\u6cd5, \u5373, \u8ba9\u8ba1\u7b97\u673a\u5b66\u4e60\u65e0\u6807\u7b7e [&#8230;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[11,18],"tags":[],"class_list":["post-620","post","type-post","status-publish","format-standard","hentry","category-11","category-18"],"_links":{"self":[{"href":"https:\/\/blog.sssn.tech\/index.php?rest_route=\/wp\/v2\/posts\/620","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/blog.sssn.tech\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blog.sssn.tech\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blog.sssn.tech\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/blog.sssn.tech\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=620"}],"version-history":[{"count":2,"href":"https:\/\/blog.sssn.tech\/index.php?rest_route=\/wp\/v2\/posts\/620\/revisions"}],"predecessor-version":[{"id":825,"href":"https:\/\/blog.sssn.tech\/index.php?rest_route=\/wp\/v2\/posts\/620\/revisions\/825"}],"wp:attachment":[{"href":"https:\/\/blog.sssn.tech\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=620"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blog.sssn.tech\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=620"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blog.sssn.tech\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=620"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}