\u968f\u673a\u68ee\u6797<\/title>\n\n<script src=\"1-randomforest_files\/jquery-1.11.3\/jquery.min.js\"><\/script>\n<meta name=\"viewport\" content=\"width=device-width, initial-scale=1\" \/>\n<link href=\"1-randomforest_files\/bootstrap-3.3.5\/css\/united.min.css\" rel=\"stylesheet\" \/>\n<script src=\"1-randomforest_files\/bootstrap-3.3.5\/js\/bootstrap.min.js\"><\/script>\n<script src=\"1-randomforest_files\/bootstrap-3.3.5\/shim\/html5shiv.min.js\"><\/script>\n<script src=\"1-randomforest_files\/bootstrap-3.3.5\/shim\/respond.min.js\"><\/script>\n<script src=\"1-randomforest_files\/jqueryui-1.11.4\/jquery-ui.min.js\"><\/script>\n<link href=\"1-randomforest_files\/tocify-1.9.1\/jquery.tocify.css\" rel=\"stylesheet\" \/>\n<script src=\"1-randomforest_files\/tocify-1.9.1\/jquery.tocify.js\"><\/script>\n<script src=\"1-randomforest_files\/navigation-1.1\/tabsets.js\"><\/script>\n<script src=\"1-randomforest_files\/navigation-1.1\/codefolding.js\"><\/script>\n\n\n<style type=\"text\/css\">code{white-space: pre;}<\/style>\n<style type=\"text\/css\">\ndiv.sourceCode { overflow-x: auto; }\ntable.sourceCode, tr.sourceCode, td.lineNumbers, td.sourceCode {\n margin: 0; padding: 0; vertical-align: baseline; border: none; }\ntable.sourceCode { width: 100%; line-height: 100%; background-color: #f8f8f8; }\ntd.lineNumbers { text-align: right; padding-right: 4px; padding-left: 4px; color: #aaaaaa; border-right: 1px solid #aaaaaa; }\ntd.sourceCode { padding-left: 5px; }\npre, code { background-color: #f8f8f8; }\ncode > span.kw { color: #204a87; font-weight: bold; } \/* Keyword *\/\ncode > span.dt { color: #204a87; } \/* DataType *\/\ncode > span.dv { color: #0000cf; } \/* DecVal *\/\ncode > span.bn { color: #0000cf; } \/* BaseN *\/\ncode > span.fl { color: #0000cf; } \/* Float *\/\ncode > span.ch { color: #4e9a06; } \/* Char *\/\ncode > span.st { color: #4e9a06; } \/* String *\/\ncode > span.co { color: #8f5902; font-style: italic; } \/* Comment *\/\ncode > span.ot { color: #8f5902; } \/* Other *\/\ncode > span.al { color: #ef2929; } \/* Alert *\/\ncode > span.fu { color: #000000; } \/* Function *\/\ncode > span.er { color: #a40000; font-weight: bold; } \/* Error *\/\ncode > span.wa { color: #8f5902; font-weight: bold; font-style: italic; } \/* Warning *\/\ncode > span.cn { color: #000000; } \/* Constant *\/\ncode > span.sc { color: #000000; } \/* SpecialChar *\/\ncode > span.vs { color: #4e9a06; } \/* VerbatimString *\/\ncode > span.ss { color: #4e9a06; } \/* SpecialString *\/\ncode > span.im { } \/* Import *\/\ncode > span.va { color: #000000; } \/* Variable *\/\ncode > span.cf { color: #204a87; font-weight: bold; } \/* ControlFlow *\/\ncode > span.op { color: #ce5c00; font-weight: bold; } \/* Operator *\/\ncode > span.pp { color: #8f5902; font-style: italic; } \/* Preprocessor *\/\ncode > span.ex { } \/* Extension *\/\ncode > span.at { color: #c4a000; } \/* Attribute *\/\ncode > span.do { color: #8f5902; font-weight: bold; font-style: italic; } \/* Documentation *\/\ncode > span.an { color: #8f5902; font-weight: bold; font-style: italic; } \/* Annotation *\/\ncode > span.cv { color: #8f5902; font-weight: bold; font-style: italic; } \/* CommentVar *\/\ncode > span.in { color: #8f5902; font-weight: bold; font-style: italic; } \/* Information *\/\ndiv.sourceCode {\n overflow-x: visible;\n}\n<\/style>\n<style type=\"text\/css\">\n pre:not([class]) {\n background-color: white;\n }\n<\/style>\n\n\n<style type=\"text\/css\">\nh1 {\n font-size: 34px;\n}\nh1.title {\n font-size: 38px;\n}\nh2 {\n font-size: 30px;\n}\nh3 {\n font-size: 24px;\n}\nh4 {\n font-size: 18px;\n}\nh5 {\n font-size: 16px;\n}\nh6 {\n font-size: 12px;\n}\n.table th:not([align]) {\n text-align: left;\n}\n<\/style>\n\n\n<\/head>\n\n<body>\n\n<style type = \"text\/css\">\n.main-container {\n max-width: 940px;\n margin-left: auto;\n margin-right: auto;\n}\ncode {\n color: inherit;\n background-color: rgba(0, 0, 0, 0.04);\n}\nimg {\n max-width:100%;\n height: auto;\n}\n.tabbed-pane {\n padding-top: 12px;\n}\n.html-widget {\n margin-bottom: 20px;\n}\nbutton.code-folding-btn:focus {\n outline: none;\n}\n<\/style>\n\n\n\n<div class=\"container-fluid main-container\">\n\n\n<script>\n$(document).ready(function () {\n window.buildTabsets(\"TOC\");\n});\n<\/script>\n\n\n<style type=\"text\/css\">\n.code-folding-btn { margin-bottom: 4px; }\n<\/style>\n<script>\n$(document).ready(function () {\n window.initializeCodeFolding(\"show\" === \"show\");\n});\n<\/script>\n\n\n\n\n<script>\n$(document).ready(function () {\n\n \/\/ move toc-ignore selectors from section div to header\n $('div.section.toc-ignore')\n .removeClass('toc-ignore')\n .children('h1,h2,h3,h4,h5').addClass('toc-ignore');\n\n \/\/ establish options\n var options = {\n selectors: \"h1,h2,h3\",\n theme: \"bootstrap3\",\n context: '.toc-content',\n hashGenerator: function (text) {\n return text.replace(\/[.\\\\\/?&!#<>]\/g, '').replace(\/\\s\/g, '_').toLowerCase();\n },\n ignoreSelector: \".toc-ignore\",\n scrollTo: 0\n };\n options.showAndHide = true;\n options.smoothScroll = true;\n\n \/\/ tocify\n var toc = $(\"#TOC\").tocify(options).data(\"toc-tocify\");\n});\n<\/script>\n\n<style type=\"text\/css\">\n\n#TOC {\n margin: 25px 0px 20px 0px;\n}\n@media (max-width: 768px) {\n#TOC {\n position: relative;\n width: 100%;\n}\n}\n\n\n.toc-content {\n padding-left: 30px;\n padding-right: 40px;\n}\n\ndiv.main-container {\n max-width: 1200px;\n}\n\ndiv.tocify {\n width: 20%;\n max-width: 260px;\n max-height: 85%;\n}\n\n@media (min-width: 768px) and (max-width: 991px) {\n div.tocify {\n width: 25%;\n }\n}\n\n@media (max-width: 767px) {\n div.tocify {\n width: 100%;\n max-width: none;\n }\n}\n\n.tocify ul, .tocify li {\n line-height: 20px;\n}\n\n.tocify-subheader .tocify-item {\n font-size: 0.90em;\n padding-left: 25px;\n text-indent: 0;\n}\n\n.tocify .list-group-item {\n border-radius: 0px;\n}\n\n\n<\/style>\n\n\n<div class=\"row-fluid\">\n<div class=\"col-xs-12 col-sm-4 col-md-3\">\n<div id=\"TOC\" class=\"tocify\">\n<\/div>\n<\/div>\n\n<div class=\"toc-content col-xs-12 col-sm-8 col-md-9\">\n\n\n\n\n<div class=\"fluid-row\" id=\"header\">\n\n<div class=\"btn-group pull-right\">\n<button type=\"button\" class=\"btn btn-default btn-xs dropdown-toggle\" data-toggle=\"dropdown\" aria-haspopup=\"true\" aria-expanded=\"false\"><span>Code<\/span> <span class=\"caret\"><\/span><\/button>\n<ul class=\"dropdown-menu\" style=\"min-width: 50px;\">\n<li><a id=\"rmd-show-all-code\" href=\"#\">Show All Code<\/a><\/li>\n<li><a id=\"rmd-hide-all-code\" href=\"#\">Hide All Code<\/a><\/li>\n<\/ul>\n<\/div>\n\n\n\n<h1 class=\"title toc-ignore\">\u968f\u673a\u68ee\u6797<\/h1>\n\n<\/div>\n\n\n<div class=\"section level1\">\n<h1><span class=\"header-section-number\">1<\/span> \u968f\u673a\u68ee\u6797\u7b80\u4ecb<\/h1>\n<p><font size=4 face=\"\u5fae\u8f6f\u96c5\u9ed1\"><\/p>\n<hr \/>\n<p>\u2003\u2003\u968f\u673a\u68ee\u6797\u662f\u4e00\u79cd\u6bd4\u8f83\u65b0\u7684\u673a\u5668\u5b66\u4e60\u6a21\u578b\uff0c\u5176\u4e0e\u4e0a\u9762\u6240\u8bb2\u7684k\u8fd1\u90bb\u3001\u6734\u7d20\u8d1d\u53f6\u65af\uff0c\u51b3\u7b56\u6811\u7b49\u8fd9\u4e9b\u7b97\u6cd5\u6700\u5927\u7684\u4e0d\u540c\u4e4b\u5904\u5c31\u662f\u5b83\u662f\u4e00\u79cd\u57fa\u4e8e\u51b3\u7b56\u6811\u7684\u96c6\u6210\u5b66\u4e60\u65b9\u6cd5\uff0c\u5176\u4e2d\u6bcf\u4e00\u9897\u6811\u90fd\u4f9d\u8d56\u4e8e\u4e00\u4e2a\u968f\u673a\u5411\u91cf\uff0c\u68ee\u6797\u4e2d\u6240\u6709\u7684\u5411\u91cf\u90fd\u662f\u72ec\u7acb\u5206\u5e03\u7684\u3002<\/p>\n<p>\u2003\u2003\u968f\u673a\u68ee\u6797\u7684\u5b9e\u8d28\u5c31\u662f\u5bf9\u6570\u636e\u96c6\u7684\u5217\u53d8\u91cf\u548c\u884c\u89c2\u6d4b\u8fdb\u884c\u968f\u673a\u5316\uff0c\u751f\u6210\u591a\u4e2a\u5206\u7c7b\u6570\uff0c\u6700\u7ec8\u5c06\u5206\u7c7b\u6811\u7ed3\u679c\u8fdb\u884c\u6c47\u603b\uff0c\u628a\u6c47\u603b\u540e\u7684\u7ed3\u679c\u4f5c\u4e3a\u6700\u7ec8\u7684\u9884\u6d4b\u7ed3\u679c\u3002<\/p>\n<\/div>\n<div class=\"section level1\">\n<h1><span class=\"header-section-number\">2<\/span> \u968f\u673a\u68ee\u6797\u539f\u7406\u53ca\u4f18\u7f3a\u70b9<\/h1>\n<hr \/>\n<p>\u2003\u2003\u6211\u4eec\u5728\u51b3\u7b56\u6811\u8fd9\u4e00\u8282\u5df2\u7ecf\u4ecb\u7ecd\u4e86\u51b3\u7b56\u6811\u7684\u539f\u7406\uff0c\u968f\u673a\u68ee\u6797\u5c31\u662f\u7531\u591a\u4e2a<strong>\u672a\u526a\u679d<\/strong>\u7684CART\u5206\u7c7b\u51b3\u7b56\u6811\u7ec4\u6210\uff0c\u5176\u4e0d\u4ec5\u53ef\u4ee5\u505a\u56de\u5f52\uff0c\u8fd8\u53ef\u4ee5\u505a\u5206\u7c7b\u3002\u5176\u505a\u56de\u5f52\u65f6\u8fd4\u56de\u7684\u7ed3\u679c\u662f\u5355\u68f5\u6811\u8f93\u51fa\u7ed3\u679c\u7684\u7b80\u5355\u5e73\u5747\uff0c\u505a\u5206\u7c7b\u65f6\u7684\u8fd4\u56de\u7ed3\u679c\u662f\u5355\u68f5\u6811\u8f93\u51fa\u7ed3\u679c\u7684\u4f17\u6570\u3002<\/p>\n<div class=\"section level2\">\n<h2><span class=\"header-section-number\">2.1<\/span> \u6784\u5efa\u6d41\u7a0b<\/h2>\n<p>\u2003\u2003\u968f\u673a\u68ee\u6797\u7684\u6784\u5efa\u6d41\u7a0b\u5e76\u4e0d\u590d\u6742\uff0c\u5176\u4e3b\u8981\u6d41\u7a0b\u5982\u4e0b\uff1a<\/p>\n<ul>\n<li>\u5e94\u7528Bootstrap\u91cd\u91c7\u6837\u65b9\u6cd5\u6709\u653e\u56de\u5730\u968f\u673a\u62bd\u53d6n\u4e2a\u65b0\u7684\u81ea\u52a9\u6837\u672c\u96c6<\/li>\n<li>\u968f\u673a\u4ece\u6240\u6709\u53d8\u91cf\u4e2d\u62bd\u53d6m\u4e2a\u53d8\u91cf\u4f5c\u4e3a\u5b50\u6570\u636e\u96c6\u7684\u53d8\u91cf<\/li>\n<li>\u5bf9k\u4e2a\u542b\u6709m\u4e2a\u53d8\u91cf\u7684\u5b50\u6570\u636e\u96c6\u5206\u522b\u6784\u5efaCART\u6811\uff0c\u5176\u4ed6\u5b50\u6570\u636e\u96c6\u4f5c\u4e3a\u6d4b\u8bd5\u96c6<\/li>\n<li>\u628a\u9700\u8981\u9884\u6d4b\u7684\u6570\u636e\u4ee3\u5165\u751f\u6210\u7684\u591a\u4e2aCART\u6811\uff0c\u6839\u636e\u6bcf\u68f5\u6811\u7684\u6295\u7968\u7ed3\u679c\u53d6\u7968\u6570\u6700\u9ad8\u7684\u4e00\u4e2a\u7c7b\u522b<\/li>\n<\/ul>\n<\/div>\n<div class=\"section level2\">\n<h2><span class=\"header-section-number\">2.2<\/span> \u6027\u80fd<\/h2>\n<ul>\n<li>\u6bcf\u68f5CART\u6811\u751f\u957f\u8d8a\u8302\u76db\uff0c\u7ec4\u6210\u7684\u968f\u673a\u68ee\u6797\u7684\u6027\u80fd\u8d8a\u597d<\/li>\n<li>\u6bcf\u68f5\u6811\u4e4b\u95f4\u72ec\u7acb\u6027\u8d8a\u9ad8\uff0c\u79df\u6210\u7684\u968f\u673a\u68ee\u6797\u7684\u6027\u80fd\u8d8a\u597d<\/li>\n<\/ul>\n<\/div>\n<div class=\"section level2\">\n<h2><span class=\"header-section-number\">2.3<\/span> \u4f18\u7f3a\u70b9<\/h2>\n<hr \/>\n<table>\n<thead>\n<tr class=\"header\">\n<th align=\"left\">\u4f18\u70b9<\/th>\n<th align=\"left\">\u7f3a\u70b9<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr class=\"odd\">\n<td align=\"left\">\u53ef\u4ee5\u9002\u7528\u4e8e\u5927\u591a\u6570\u95ee\u9898\uff0c\u53ef\u5904\u7406\u566a\u58f0\u548c\u7f3a\u5931\u503c\uff1b\u5206\u7c7b\u548c\u8fde\u7eed\u6027\u7279\u5f81\u6570\u636e<\/td>\n<td align=\"left\">\u8bad\u7ec3\u548c\u9884\u6d4b\u6bd4\u8f83\u6162<\/td>\n<\/tr>\n<tr class=\"even\">\n<td align=\"left\">\u4e24\u4e2a\u968f\u673a\u6027\u7684\u5f15\u5165\uff0c\u4f7f\u6a21\u578b\u4e0d\u5bb9\u6613\u8fc7\u62df\u5408<\/td>\n<td align=\"left\">\u5728\u5206\u7c7b\u95ee\u9898\u4e2d\uff0c\u82e5\u76ee\u6807\u6570\u636e\u96c6\u504f\u5c0f\u5e76\u53d8\u91cf\u7c7b\u522b\u8fc7\u591a\uff0c\u5219\u8868\u73b0\u8f83\u5dee<\/td>\n<\/tr>\n<tr class=\"odd\">\n<td align=\"left\">\u5904\u7406\u9ad8\u7ef4\u5ea6\u7684\u6570\u636e\u65f6\uff0c\u53ef\u4ee5\u4e0d\u7528\u505a\u5f88\u8be6\u7ec6\u7684\u5f81\u9009\u62e9<\/td>\n<td align=\"left\"><\/td>\n<\/tr>\n<tr class=\"even\">\n<td align=\"left\">\u5728\u521b\u5efa\u968f\u673a\u68ee\u6797\u7684\u65f6\u5019\uff0c\u5bf9generlization error\u4f7f\u7528\u7684\u662f\u65e0\u504f\u4f30\u8ba1<\/td>\n<td align=\"left\"><\/td>\n<\/tr>\n<tr class=\"odd\">\n<td align=\"left\">\u53ef\u4ee5\u8fd4\u56de\u53d8\u91cf\u7684\u91cd\u8981\u6027<\/td>\n<td align=\"left\"><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<\/div>\n<div class=\"section level1\">\n<h1><span class=\"header-section-number\">3<\/span> \u6848\u4f8b\u5b9e\u6218<\/h1>\n<p>\u2003\u2003\u672c\u6848\u4f8b\u7684\u4e3b\u8981\u5185\u5bb9\u5c31\u662f\u4f7f\u7528\u968f\u673a\u68ee\u6797\u5bf9R\u4e2d\u81ea\u5e26\u7684iris\u6570\u636e\u96c6\u8fdb\u884c\u5206\u7c7b\u3002<\/p>\n<p>\u2003\u2003\u5728R\u4e2d\u5e38\u7528randomforst\u7a0b\u5e8f\u5305\u7684\u5b9e\u73b0\u968f\u673a\u68ee\u6797\u7b97\u6cd5\uff0c\u8be5\u5305\u4e3b\u8981\u6d89\u53ca\u52303\u4e2a\u91cd\u8981\u7684\u51fd\u6570\uff0c\u6bcf\u4e2a\u53c2\u6570\u7684\u8be6\u7ec6\u4fe1\u606f\u8be6\u89c1\u4e0b\u65b9\uff1a<\/p>\n<p><strong>1)randomForest()\u51fd\u6570\u7528\u4e8e\u6784\u5efa\u968f\u673a\u68ee\u6797\u6a21\u578b<\/strong><\/p>\n<p>randomForest(formula, data=NULL, \u2026, subset, na.action=na.fail)<\/p>\n<p>randomForest(x, y=NULL, xtest=NULL, ytest=NULL, ntree=500,<br> \u2003\u2003\u2003\u2003\u2003\u2003\u2003mtry=if (!is.null(y) && !is.factor(y))<br> \u2003\u2003\u2003\u2003\u2003\u2003\u2003max(floor(ncol(x)\/3), 1) else floor(sqrt(ncol(x))),<br> \u2003\u2003\u2003\u2003\u2003\u2003\u2003replace=TRUE, classwt=NULL, cutoff, strata,<br> \u2003\u2003\u2003\u2003\u2003\u2003\u2003sampsize = if (replace) nrow(x) else ceiling(.632*nrow(x)),<br> \u2003\u2003\u2003\u2003\u2003\u2003\u2003nodesize = if (!is.null(y) && !is.factor(y)) 5 else 1,<br> \u2003\u2003\u2003\u2003\u2003\u2003\u2003maxnodes = NULL,<br> \u2003\u2003\u2003\u2003\u2003\u2003\u2003importance=FALSE, localImp=FALSE, nPerm=1,<br> \u2003\u2003\u2003\u2003\u2003\u2003\u2003proximity, oob.prox=proximity,<br> \u2003\u2003\u2003\u2003\u2003\u2003\u2003norm.votes=TRUE, do.trace=FALSE,<br> \u2003\u2003\u2003\u2003\u2003\u2003\u2003keep.forest=!is.null(y) && is.null(xtest), corr.bias=FALSE,<br> \u2003\u2003\u2003\u2003\u2003\u2003\u2003keep.inbag=FALSE, \u2026)<\/p>\n<ul>\n<li><strong>formula\uff1a<\/strong>\u6307\u5b9a\u6a21\u578b\u7684\u516c\u5f0f\u5f62\u5f0f\uff0c\u7c7b\u4f3c\u4e8ey~x1+x2+x3\u2026;<\/li>\n<li><strong>data\uff1a<\/strong>\u6307\u5b9a\u5206\u6790\u7684\u6570\u636e\u96c6\uff1b<\/li>\n<li><strong>subset\uff1a<\/strong>\u4ee5\u5411\u91cf\u7684\u5f62\u5f0f\u786e\u5b9a\u6837\u672c\u6570\u636e\u96c6\uff1b<\/li>\n<li><strong>na.action\uff1a<\/strong>\u6307\u5b9a\u6570\u636e\u96c6\u4e2d\u7f3a\u5931\u503c\u7684\u5904\u7406\u65b9\u6cd5\uff0c\u9ed8\u8ba4\u4e3ana.fail\uff0c\u5373\u4e0d\u5141\u8bb8\u51fa\u73b0\u7f3a\u5931\u503c\uff0c\u4e5f\u53ef\u4ee5\u6307\u5b9a\u4e3ana.omit\uff0c\u5373\u5220\u9664\u7f3a\u5931\u6837\u672c\uff1b<\/li>\n<li><strong>x\uff1a<\/strong>\u6307\u5b9a\u6a21\u578b\u7684\u89e3\u91ca\u53d8\u91cf\uff0c\u53ef\u4ee5\u662f\u77e9\u9635\uff0c\u4e5f\u53ef\u4ee5\u662f\u6570\u636e\u6846\uff1b<\/li>\n<li><strong>y\uff1a<\/strong>\u6307\u5b9a\u6a21\u578b\u7684\u56e0\u53d8\u91cf\uff0c\u53ef\u4ee5\u662f\u79bb\u6563\u7684\u56e0\u5b50\uff0c\u4e5f\u53ef\u4ee5\u662f\u8fde\u7eed\u7684\u6570\u503c\uff0c\u5206\u522b\u5bf9\u5e94\u4e8e\u968f\u673a\u68ee\u6797\u7684\u5206\u7c7b\u6a21\u578b\u548c\u9884\u6d4b\u6a21\u578b\u3002\u8fd9\u91cc\u9700\u8981\u8bf4\u660e\u7684\u662f\uff0c\u5982\u679c\u4e0d\u6307\u5b9ay\u503c\uff0c\u5219\u968f\u673a\u68ee\u6797\u5c06\u662f\u4e00\u4e2a\u65e0\u76d1\u7763\u7684\u6a21\u578b\uff1b <strong>xtest<\/strong>\u548c<strong>ytest<\/strong>\u7528\u4e8e\u9884\u6d4b\u7684\u6d4b\u8bd5\u96c6\uff1b<\/li>\n<li><strong>ntree\uff1a<\/strong>\u6307\u5b9a\u968f\u673a\u68ee\u6797\u6240\u5305\u542b\u7684\u51b3\u7b56\u6811\u6570\u76ee\uff0c\u9ed8\u8ba4\u4e3a500\uff1b<\/li>\n<li><strong>mtry\uff1a<\/strong>\u6307\u5b9a\u8282\u70b9\u4e2d\u7528\u4e8e\u4e8c\u53c9\u6811\u7684\u53d8\u91cf\u4e2a\u6570\uff0c\u9ed8\u8ba4\u60c5\u51b5\u4e0b\u6570\u636e\u96c6\u53d8\u91cf\u4e2a\u6570\u7684\u4e8c\u6b21\u65b9\u6839(\u5206\u7c7b\u6a21\u578b)\u6216\u4e09\u5206\u4e4b\u4e00(\u9884\u6d4b\u6a21\u578b)\u3002\u4e00\u822c\u662f\u9700\u8981\u8fdb\u884c\u4eba\u4e3a\u7684\u9010\u6b21\u6311\u9009\uff0c\u786e\u5b9a\u6700\u4f73\u7684m\u503c\uff1b<\/li>\n<li><strong>replace\uff1a<\/strong>\u6307\u5b9aBootstrap\u968f\u673a\u62bd\u6837\u7684\u65b9\u5f0f\uff0c\u9ed8\u8ba4\u4e3a\u6709\u653e\u56de\u7684\u62bd\u6837\uff1b<\/li>\n<li><strong>classwt\uff1a<\/strong>\u6307\u5b9a\u5206\u7c7b\u6c34\u5e73\u7684\u6743\u91cd\uff0c\u5bf9\u4e8e\u56de\u5f52\u6a21\u578b\uff0c\u8be5\u53c2\u6570\u65e0\u6548\uff1b<\/li>\n<li><strong>strata\uff1a<\/strong>\u4e3a\u56e0\u5b50\u5411\u91cf\uff0c\u7528\u4e8e\u5206\u5c42\u62bd\u6837\uff1b<\/li>\n<li><strong>sampsize\uff1a<\/strong>\u7528\u4e8e\u6307\u5b9a\u6837\u672c\u5bb9\u91cf\uff0c\u4e00\u822c\u4e0e\u53c2\u6570strata\u8054\u5408\u4f7f\u7528\uff0c\u6307\u5b9a\u5206\u5c42\u62bd\u6837\u4e2d\u5c42\u7684\u6837\u672c\u91cf\uff1b<\/li>\n<li><strong>nodesize\uff1a<\/strong>\u6307\u5b9a\u51b3\u7b56\u6811\u8282\u70b9\u7684\u6700\u5c0f\u4e2a\u6570\uff0c\u9ed8\u8ba4\u60c5\u51b5\u4e0b\uff0c\u5224\u522b\u6a21\u578b\u4e3a1\uff0c\u56de\u5f52\u6a21\u578b\u4e3a5\uff1b<\/li>\n<li><strong>maxnodes\uff1a<\/strong>\u6307\u5b9a\u51b3\u7b56\u6811\u8282\u70b9\u7684\u6700\u5927\u4e2a\u6570\uff1b<\/li>\n<li><strong>importance\uff1a<\/strong>\u903b\u8f91\u53c2\u6570\uff0c\u662f\u5426\u8ba1\u7b97\u5404\u4e2a\u53d8\u91cf\u5728\u6a21\u578b\u4e2d\u7684\u91cd\u8981\u6027\uff0c\u9ed8\u8ba4\u4e0d\u8ba1\u7b97\uff0c\u8be5\u53c2\u6570\u4e3b\u8981\u7ed3\u5408importance()\u51fd\u6570\u4f7f\u7528\uff1b<\/li>\n<li><strong>proximity\uff1a<\/strong>\u903b\u8f91\u53c2\u6570\uff0c\u662f\u5426\u8ba1\u7b97\u6a21\u578b\u7684\u4e34\u8fd1\u77e9\u9635\uff0c\u4e3b\u8981\u7ed3\u5408MDSplot()\u51fd\u6570\u4f7f\u7528\uff1b<\/li>\n<li><strong>oob.prox\uff1a<\/strong>\u662f\u5426\u57fa\u4e8eOOB\u6570\u636e\u8ba1\u7b97\u4e34\u8fd1\u77e9\u9635\uff1b<\/li>\n<li><strong>norm.votes\uff1a<\/strong>\u663e\u793a\u6295\u7968\u683c\u5f0f\uff0c\u9ed8\u8ba4\u4ee5\u767e\u5206\u6bd4\u7684\u5f62\u5f0f\u5c55\u793a\u6295\u7968\u7ed3\u679c\uff0c\u4e5f\u53ef\u4ee5\u91c7\u7528\u7edd\u5bf9\u6570\u7684\u5f62\u5f0f\uff1b<\/li>\n<li><strong>do.trace\uff1a<\/strong>\u662f\u5426\u8f93\u51fa\u66f4\u8be6\u7ec6\u7684\u968f\u673a\u68ee\u6797\u6a21\u578b\u8fd0\u884c\u8fc7\u7a0b\uff0c\u9ed8\u8ba4\u4e0d\u8f93\u51fa\uff1b<\/li>\n<li><strong>keep.forest\uff1a<\/strong>\u662f\u5426\u4fdd\u7559\u6a21\u578b\u7684\u8f93\u51fa\u5bf9\u8c61\uff0c\u5bf9\u4e8e\u7ed9\u5b9axtest\u503c\u540e\uff0c\u9ed8\u8ba4\u5c06\u4e0d\u4fdd\u7559\u7b97\u6cd5\u7684\u8fd0\u7b97\u7ed3\u679c\u3002<\/li>\n<\/ul>\n<p><strong>2)importance()\u51fd\u6570\u7528\u4e8e\u8ba1\u7b97\u6a21\u578b\u53d8\u91cf\u7684\u91cd\u8981\u6027<\/strong><\/p>\n<p>importance(x, type=NULL, class=NULL, scale=TRUE, \u2026)<\/p>\n<ul>\n<li><strong>x\uff1a<\/strong>\u4e3arandomForest\u5bf9\u8c61\uff1b<\/li>\n<li><strong>type\u201d<\/strong>\u53ef\u4ee5\u662f1\uff0c\u4e5f\u53ef\u4ee5\u662f2\uff0c\u7528\u4e8e\u5224\u522b\u8ba1\u7b97\u53d8\u91cf\u91cd\u8981\u6027\u7684\u65b9\u6cd5\uff0c1\u8868\u793a\u4f7f\u7528\u7cbe\u5ea6\u5e73\u5747\u8f83\u5c11\u503c\u4f5c\u4e3a\u5ea6\u91cf\u6807\u51c6\uff1b2\u8868\u793a\u91c7\u7528\u8282\u70b9\u4e0d\u7eaf\u5ea6\u7684\u5e73\u5747\u51cf\u5c11\u503c\u6700\u4e3a\u5ea6\u91cf\u6807\u51c6\u3002\u503c\u8d8a\u5927\u8bf4\u660e\u53d8\u91cf\u7684\u91cd\u8981\u6027\u8d8a\u5f3a\uff1b<\/li>\n<li><strong>scale\uff1a<\/strong>\u9ed8\u8ba4\u5bf9\u53d8\u91cf\u7684\u91cd\u8981\u6027\u503c\u8fdb\u884c\u6807\u51c6\u5316\u3002<\/li>\n<\/ul>\n<p><strong>3)MDSplot()\u7ed8\u5236\u5efa\u7acb\u6a21\u578b\u8fc7\u7a0b\u4e2d\u4ea7\u751f\u7684\u4e34\u8fd1\u77e9\u9635\u7ecf\u8fc7\u6807\u51c6\u5316\u540e\u7684\u5750\u6807\u56fe\uff0c\u5c31\u662f\u53ef\u4ee5\u5c06\u9ad8\u4f4d\u56fe\u7f29\u653e\u5230\u4efb\u610f\u5c0f\u7684\u7ef4\u5ea6\u4e0b\u6765\u89c2\u770b\u6a21\u578b\u5404\u4e2a\u7c7b\u522b\u5728\u4e0d\u540c\u7ef4\u5ea6\u4e0b\u7684\u5206\u5e03\u60c5\u51b5<\/strong><\/p>\n<p>MDSplot(rf, fac, k=2, palette=NULL, pch=20, \u2026)<\/p>\n<ul>\n<li><strong>rf\uff1a<\/strong>\u4e3arandomForest\u5bf9\u8c61\uff0c\u9700\u8981\u8bf4\u660e\u7684\u662f\uff0c\u5728\u6784\u5efa\u968f\u673a\u68ee\u6797\u6a21\u578b\u65f6\u5fc5\u987b\u6307\u5b9a\u8ba1\u7b97\u4e34\u8fd1\u77e9\u9635\uff0c\u5373\u8bbe\u7f6eproximity\u53c2\u6570\u4e3aTRUE\uff1b<\/li>\n<li><strong>fac\uff1a<\/strong>\u6307\u5b9a\u968f\u673a\u68ee\u6797\u6a21\u578b\u4e2d\u6240\u4f7f\u7528\u5230\u7684\u56e0\u5b50\u5411\u91cf(\u56e0\u53d8\u91cf)\uff1b<\/li>\n<li><strong>palette\uff1a<\/strong>\u6307\u5b9a\u6240\u7ed8\u56fe\u5f62\u4e2d\u5404\u4e2a\u7c7b\u522b\u7684\u989c\u8272\uff1b<\/li>\n<li><strong>pch\uff1a<\/strong>\u6307\u5b9a\u6240\u7ed8\u56fe\u5f62\u4e2d\u5404\u4e2a\u7c7b\u522b\u5f62\u72b6\uff1b<\/li>\n<\/ul>\n<p><strong>4)rfImpute()\u51fd\u6570\u53ef\u4e3a\u5b58\u5728\u7f3a\u5931\u503c\u7684\u6570\u636e\u96c6\u8fdb\u884c\u63d2\u8865(\u968f\u673a\u68ee\u6797\u6cd5)\uff0c\u5f97\u5230\u6700\u4f18\u7684\u6837\u672c\u62df\u5408\u503c<\/strong><\/p>\n<p>rfImpute(x, y, iter=5, ntree=300, \u2026)<\/p>\n<p>rfImpute(x, data, \u2026, subset)<\/p>\n<ul>\n<li><strong>x\uff1a<\/strong>\u4e3a\u5b58\u5728\u7f3a\u5931\u503c\u7684\u6570\u636e\u96c6\uff1b<\/li>\n<li><strong>y\uff1a<\/strong>\u4e3a\u56e0\u53d8\u91cf\uff0c\u4e0d\u53ef\u4ee5\u5b58\u5728\u7f3a\u5931\u60c5\u51b5\uff1b<\/li>\n<li><strong>iter\uff1a<\/strong>\u6307\u5b9a\u63d2\u503c\u8fc7\u7a0b\u4e2d\u8fed\u4ee3\u6b21\u6570\uff1b<\/li>\n<li><strong>ntree\uff1a<\/strong>\u6307\u5b9a\u6bcf\u6b21\u8fed\u4ee3\u751f\u6210\u7684\u968f\u673a\u68ee\u6797\u4e2d\u51b3\u7b56\u6811\u6570\u91cf\uff1b<\/li>\n<li><strong>subset\uff1a<\/strong>\u4ee5\u5411\u91cf\u7684\u5f62\u5f0f\u6307\u5b9a\u6837\u672c\u96c6\u3002<\/li>\n<\/ul>\n<p><strong>5)treesize()\u51fd\u6570\u7528\u4e8e\u8ba1\u7b97\u968f\u673a\u68ee\u6797\u4e2d\u6bcf\u68f5\u6811\u7684\u8282\u70b9\u4e2a\u6570<\/strong><\/p>\n<p>treesize(x, terminal=TRUE)<\/p>\n<ul>\n<li><strong>x\uff1a<\/strong>\u4e3arandomForest\u5bf9\u8c61\uff1b<\/li>\n<li><strong>terminal\uff1a<\/strong>\u6307\u5b9a\u8ba1\u7b97\u8282\u70b9\u6570\u76ee\u7684\u65b9\u5f0f\uff0c\u9ed8\u8ba4\u53ea\u8ba1\u7b97\u6bcf\u68f5\u6811\u7684\u6839\u8282\u70b9\uff0c\u8bbe\u7f6e\u4e3aFALSE\u65f6\u5c06\u8ba1\u7b97\u6240\u6709\u8282\u70b9(\u6839\u8282\u70b9+\u53f6\u8282\u70b9)\u3002<\/li>\n<\/ul>\n<hr \/>\n<div class=\"section level2\">\n<h2><span class=\"header-section-number\">3.1<\/span> \u83b7\u53d6\u5e76\u63a2\u7d22\u6570\u636e<\/h2>\n<div class=\"sourceCode\"><pre class=\"sourceCode r\"><code class=\"sourceCode r\">mydata <-<span class=\"st\"> <\/span>iris\n<span class=\"kw\">str<\/span>(mydata)<\/code><\/pre><\/div>\n<pre><code>## 'data.frame': 150 obs. of 5 variables:\n## $ Sepal.Length: num 5.1 4.9 4.7 4.6 5 5.4 4.6 5 4.4 4.9 ...\n## $ Sepal.Width : num 3.5 3 3.2 3.1 3.6 3.9 3.4 3.4 2.9 3.1 ...\n## $ Petal.Length: num 1.4 1.4 1.3 1.5 1.4 1.7 1.4 1.5 1.4 1.5 ...\n## $ Petal.Width : num 0.2 0.2 0.2 0.2 0.2 0.4 0.3 0.2 0.2 0.1 ...\n## $ Species : Factor w\/ 3 levels "setosa","versicolor",..: 1 1 1 1 1 1 1 1 1 1 ...<\/code><\/pre>\n<div class=\"sourceCode\"><pre class=\"sourceCode r\"><code class=\"sourceCode r\"><span class=\"kw\">summary<\/span>(mydata)<\/code><\/pre><\/div>\n<pre><code>## Sepal.Length Sepal.Width Petal.Length Petal.Width \n## Min. :4.300 Min. :2.000 Min. :1.000 Min. :0.100 \n## 1st Qu.:5.100 1st Qu.:2.800 1st Qu.:1.600 1st Qu.:0.300 \n## Median :5.800 Median :3.000 Median :4.350 Median :1.300 \n## Mean :5.843 Mean :3.057 Mean :3.758 Mean :1.199 \n## 3rd Qu.:6.400 3rd Qu.:3.300 3rd Qu.:5.100 3rd Qu.:1.800 \n## Max. :7.900 Max. :4.400 Max. :6.900 Max. :2.500 \n## Species \n## setosa :50 \n## versicolor:50 \n## virginica :50 \n## \n## \n## <\/code><\/pre>\n<p>\u2003\u2003\u4ece\u4e0a\u8ff0\u7b80\u5355\u7684\u6570\u636e\u63a2\u7d22\u4e2d\u53d1\u73b0\uff0c\u6570\u636e\u4e00\u5171\u4e94\u5217\u3002\u5176\u4e2d\u56db\u5217\u662f\u6570\u503c\u578b\uff0c\u4e00\u5217\u662f\u56e0\u5b50\u578b\uff0c\u5e76\u4e14\u56e0\u5b50\u578b\u53d8\u91cf\u7684\u56e0\u5b50\u6c34\u5e73\u4e00\u81f4\uff0c\u6bcf\u4e2a\u6c34\u5e73\u7684\u89c2\u6d4b\u5747\u662f50\u4e2a\u3002<\/p>\n<\/div>\n<div class=\"section level2\">\n<h2><span class=\"header-section-number\">3.2<\/span> \u5206\u5c42\u62bd\u6837<\/h2>\n<p>\u2003\u2003\u5206\u5c42\u62bd\u6837\uff0c\u53c8\u79f0\u5206\u7ec4\u62bd\u6837\u3002\u662f\u4e00\u79cd\u6bd4SRS\u66f4\u7cbe\u51c6\u7684\u968f\u673a\u62bd\u6837\u6cd5\uff0c\u6240\u7528\u7684\u65b9\u6cd5\u662f\u8ddf\u636e\u6211\u4eec\u7684\u7814\u7a76\u6027\u8d28\uff0c\u4f9d\u7167\u76f8\u5173\u7684\u6761\u4ef6\u628a\u6bcd\u7fa4\u4f53\u4e2d\u7684\u4e2a\u4f53\u5206\u6210\u4e0d\u540c\u7684\u5c42\u522b\u6216\u7ec4\u522b(strata)\uff0c\u518d\u5206\u522b\u4ece\u6bcf\u4e00\u5c42\u522b\u6216\u7ec4\u522b\u4e2d\u7684\u4e2a\u4f53\u968f\u673a\u62bd\u51fa\u4e00\u5b9a\u7684\u4e2a\u4f53\u6765\u7ec4\u6210\u6837\u672c\u3002<\/p>\n<p>\u2003\u2003\u5728caret\u7a0b\u5e8f\u5305\u4e2d\u63d0\u4f9b\u4e86\u4e00\u79cd\u975e\u5e38\u65b9\u4fbf\u7684\u5206\u5c42\u62bd\u6837\u51fd\u6570<strong>createDataPartition()<\/strong>\uff0c\u4e0b\u9762\u662f\u8be5\u51fd\u6570\u7684\u53c2\u6570\u89e3\u91ca\uff1a<\/p>\n<p>createDataPartition(y, times = 1, p = 0.5, list = TRUE, groups = min(5, length(y)))<\/p>\n<ul>\n<li><strong>y\uff1a<\/strong>\u6307\u5b9a\u6570\u636e\u96c6\u4e2d\u7684\u8f93\u51fa\u53d8\u91cf<\/li>\n<li><strong>times\uff1a<\/strong>\u6307\u5b9a\u521b\u5efa\u7684\u6837\u672c\u4e2a\u6570\uff0c\u9ed8\u8ba4\u7b80\u5355\u968f\u673a\u62bd\u53d6\u4e00\u7ec4\u6837\u672c<\/li>\n<li><strong>p\uff1a<\/strong>\u6307\u5b9a\u6570\u636e\u96c6\u4e2d\u7528\u4e8e\u8bad\u7ec3\u96c6\u7684\u6bd4\u4f8b<\/li>\n<li><strong>list\uff1a<\/strong>\u662f\u5426\u5df2\u5217\u8868\u6216\u77e9\u9635\u7684\u5f62\u5f0f\u5b58\u50a8\u968f\u673a\u62bd\u53d6\u7684\u7d22\u5f15\u53f7\uff0c\u9ed8\u8ba4\u4e3aTRUE<\/li>\n<li><strong>groups\uff1a<\/strong>\u5982\u679c\u8f93\u51fa\u53d8\u91cf\u4e3a\u6570\u503c\u578b\u6570\u636e\uff0c\u5219\u9ed8\u8ba4\u6309\u5206\u4f4d\u6570\u5206\u7ec4\u8fdb\u884c\u53d6\u6837<\/li>\n<\/ul>\n<div class=\"sourceCode\"><pre class=\"sourceCode r\"><code class=\"sourceCode r\"><span class=\"co\"># install.packages("caret")<\/span>\n<span class=\"kw\">library<\/span>(caret)\n\n<span class=\"kw\">set.seed<\/span>(<span class=\"dv\">45<\/span>)\nidx <-<span class=\"st\"> <\/span><span class=\"kw\">createDataPartition<\/span>(<span class=\"dt\">y =<\/span> mydata$Species, <span class=\"dt\">p =<\/span> <span class=\"fl\">0.7<\/span>, <span class=\"dt\">list =<\/span> F)\n\ntrainset <-<span class=\"st\"> <\/span>mydata[idx, ]\ntestset <-<span class=\"st\"> <\/span>mydata[-idx, ]\n\n<span class=\"kw\">prop.table<\/span>(<span class=\"kw\">table<\/span>(mydata$Species)) <span class=\"co\"># \u8ba1\u7b97\u539f\u6570\u636e\u96c6\u4e2dSpecies\u7684\u5360\u6bd4<\/span><\/code><\/pre><\/div>\n<pre><code>## \n## setosa versicolor virginica \n## 0.3333333 0.3333333 0.3333333<\/code><\/pre>\n<div class=\"sourceCode\"><pre class=\"sourceCode r\"><code class=\"sourceCode r\"><span class=\"kw\">prop.table<\/span>(<span class=\"kw\">table<\/span>(trainset$Species)) <span class=\"co\"># \u8ba1\u7b97\u8bad\u7ec3\u96c6\u4e2dSpecies\u7684\u5360\u6bd4<\/span><\/code><\/pre><\/div>\n<pre><code>## \n## setosa versicolor virginica \n## 0.3333333 0.3333333 0.3333333<\/code><\/pre>\n<div class=\"sourceCode\"><pre class=\"sourceCode r\"><code class=\"sourceCode r\"><span class=\"kw\">prop.table<\/span>(<span class=\"kw\">table<\/span>(testset$Species)) <span class=\"co\"># \u8ba1\u7b97\u6d4b\u8bd5\u96c6\u4e2dSpecies\u7684\u5360\u6bd4<\/span><\/code><\/pre><\/div>\n<pre><code>## \n## setosa versicolor virginica \n## 0.3333333 0.3333333 0.3333333<\/code><\/pre>\n<p>\u2003\u2003\u901a\u8fc7\u5206\u5c42\u62bd\u6837\uff0c\u6211\u4eec\u628a\u6570\u636e\u62c6\u5206\u4e3a\u4e86\u8bad\u7ec3\u96c6\u548c\u6d4b\u8bd5\u96c6\uff0c\u5e76\u8ba1\u7b97\u5176\u5bf9\u5e94\u7684\u56e0\u53d8\u91cf\u7684\u6bd4\u4f8b\uff0c\u53d1\u73b0\u6bcf\u4e2a\u6570\u636e\u96c6\u4e2d\u5404\u4e2a\u7c7b\u522b\u7684\u6bd4\u4f8b\u5747\u662f0.33\uff0c\u8bf4\u660e\u8fbe\u5230\u4e86\u5206\u5c42\u62bd\u6837\u7684\u76ee\u7684\u3002<\/p>\n<\/div>\n<div class=\"section level2\">\n<h2><span class=\"header-section-number\">3.3<\/span> \u8bad\u7ec3\u6a21\u578b<\/h2>\n<p>\u2003\u2003\u6211\u4eec\u4f7f\u7528\u4e0a\u9762\u63d0\u5230\u7684<strong>randomForest()<\/strong>\u51fd\u6570\u5bf9\u8bad\u7ec3\u96c6\u8bad\u7ec3\u6a21\u578b\uff0c\u8bbe\u7f6e\u968f\u673a\u53d8\u91cf\u7684\u4e2a\u6570\u4e3a3\uff0c\u6811\u7684\u4e2a\u6570\u4e3a30\uff0c\u5e76\u4e14\u8ba1\u7b97\u5176\u53d8\u91cf\u91cd\u8981\u6027\u3002<\/p>\n<div class=\"sourceCode\"><pre class=\"sourceCode r\"><code class=\"sourceCode r\"><span class=\"co\"># install.packages("randomForest")<\/span>\n<span class=\"kw\">library<\/span>(randomForest)\n\n<span class=\"kw\">set.seed<\/span>(<span class=\"dv\">45<\/span>)\nrf <-<span class=\"st\"> <\/span><span class=\"kw\">randomForest<\/span>(Species ~., <span class=\"dt\">data =<\/span> trainset, <span class=\"dt\">mtry =<\/span> <span class=\"dv\">3<\/span>, <span class=\"dt\">ntree =<\/span> <span class=\"dv\">30<\/span>, <span class=\"dt\">importance =<\/span> T)<\/code><\/pre><\/div>\n<\/div>\n<div class=\"section level2\">\n<h2><span class=\"header-section-number\">3.4<\/span> \u5c55\u793a\u53d8\u91cf\u91cd\u8981\u6027<\/h2>\n<div class=\"sourceCode\"><pre class=\"sourceCode r\"><code class=\"sourceCode r\">imp <-<span class=\"st\"> <\/span><span class=\"kw\">importance<\/span>(<span class=\"dt\">x =<\/span> rf) <span class=\"co\"># \u8ba1\u7b97\u53d8\u91cf\u91cd\u8981\u6027<\/span>\nimp<\/code><\/pre><\/div>\n<pre><code>## setosa versicolor virginica MeanDecreaseAccuracy\n## Sepal.Length 0.000000 2.659596 1.428697 3.458823\n## Sepal.Width 0.000000 0.000000 2.127039 2.045518\n## Petal.Length 4.705308 6.126779 5.735264 6.413416\n## Petal.Width 6.510190 10.718260 11.020814 10.340348\n## MeanDecreaseGini\n## Sepal.Length 1.118633\n## Sepal.Width 1.261948\n## Petal.Length 24.540647\n## Petal.Width 42.307979<\/code><\/pre>\n<div class=\"sourceCode\"><pre class=\"sourceCode r\"><code class=\"sourceCode r\"><span class=\"kw\">varImpPlot<\/span>(rf) <span class=\"co\"># \u5c55\u793a\u53d8\u91cf\u91cd\u8981\u6027<\/span><\/code><\/pre><\/div>\n<p><img decoding=\"async\" src=\"1-randomforest_files\/figure-html\/unnamed-chunk-4-1.png\" width=\"672\" \/><\/p>\n<p>\u2003\u2003\u4e0a\u9762\u4f7f\u7528MeanDecreaseAccuracy\u548cMeanDecreaseGini\u4e24\u79cd\u6307\u6807\u8861\u91cf\u4e86\u5404\u4e2a\u53d8\u91cf\u7684\u91cd\u8981\u6027\uff0c\u53d1\u73b0\u6700\u91cd\u8981\u7684\u662fPatal.Width\uff0c\u5176\u6b21\u662fPatal.Length\u8fd9\u4e24\u4e2a\u53d8\u91cf\uff0c\u4ece\u4e00\u5b9a\u7a0b\u5ea6\u4e0a\u4e5f\u8bf4\u660e\u4e86\u9e22\u5c3e\u82b1\u7684\u5206\u7c7b\u4e0e\u82b1\u74e3\u6709\u6bd4\u8f83\u5927\u7684\u5173\u7cfb\u3002<\/p>\n<\/div>\n<div class=\"section level2\">\n<h2><span class=\"header-section-number\">3.5<\/span> \u9884\u6d4b\u4e14\u8bc4\u4f30<\/h2>\n<div class=\"sourceCode\"><pre class=\"sourceCode r\"><code class=\"sourceCode r\">pred <-<span class=\"st\"> <\/span><span class=\"kw\">predict<\/span>(rf, testset[-<span class=\"dv\">5<\/span>]) <span class=\"co\"># \u5bf9\u6d4b\u8bd5\u96c6\u8fdb\u884c\u9884\u6d4b<\/span>\n<span class=\"kw\">table<\/span>(pred, testset$Species)<\/code><\/pre><\/div>\n<pre><code>## \n## pred setosa versicolor virginica\n## setosa 15 0 0\n## versicolor 0 15 1\n## virginica 0 0 14<\/code><\/pre>\n<p>\u2003\u2003\u4ece\u6df7\u6dc6\u77e9\u9635\u4e2d\u53ef\u4ee5\u770b\u51fa\uff0c\u4ec5\u6709\u4e00\u4e2a\u6837\u672c\u88ab\u9884\u6d4b\u9519\u8bef(\u4e00\u4e2avirginica\u7684\u9e22\u5c3e\u82b1\u88ab\u9519\u8bef\u7684\u5206\u7c7b\u4e3a\u4e86versicolor)\uff0c\u6539\u6a21\u578b\u7684\u5206\u7c7b\u6548\u679c\u8fd8\u662f\u975e\u5e38\u597d\u7684\u3002<\/p>\n<\/div>\n<\/div>\n<div class=\"section level1\">\n<h1><span class=\"header-section-number\">4<\/span> \u53c2\u8003\u6587\u732e<\/h1>\n<hr \/>\n<p>[1] \u5361\u5df4\u79d1\u5f17. R\u8bed\u8a00\u5b9e\u6218[M]. \u4eba\u6c11\u90ae\u7535\u51fa\u7248\u793e, 2013.<br> [2] \u673a\u5668\u5b66\u4e60\u2014\u2014\u968f\u673a\u68ee\u6797\u7b97\u6cd5\u53ca\u539f\u7406. <a href=\"https:\/\/blog.csdn.net\/nieson2012\/article\/details\/51279332v\" class=\"uri\">https:\/\/blog.csdn.net\/nieson2012\/article\/details\/51279332v<\/a>. 2016.<br> [3] \u6559\u4f60\u4f7f\u7528caret\u5305(\u4e00)\u2013\u6570\u636e\u9884\u5904\u7406. <a href=\"https:\/\/mp.weixin.qq.com\/s\/EXq9B-imnX6D27okYvPGkw\" class=\"uri\">https:\/\/mp.weixin.qq.com\/s\/EXq9B-imnX6D27okYvPGkw<\/a>. 2016<br> [4] \u57fa\u4e8eR\u8bed\u8a00\u7684\u968f\u673a\u68ee\u6797\u7b97\u6cd5\u8fd0\u7528. <a href=\"https:\/\/mp.weixin.qq.com\/s?__biz=MzIxNjA2ODUzNg\" class=\"uri\">https:\/\/mp.weixin.qq.com\/s?__biz=MzIxNjA2ODUzNg<\/a>==&mid=400806663&idx=1&sn=51b4b7a44a33606bd9262e208f91c2df&mpshare=1&scene=23&srcid=0621JANvo04Zy7uaMQt5kxbg#rd. 2015<br> [6] \u673a\u5668\u5b66\u4e60\u5341\u5927\u7b97\u6cd5\u20148. \u968f\u673a\u68ee\u6797\u7b97\u6cd5. <a href=\"https:\/\/blog.csdn.net\/julialove102123\/article\/details\/78405284\" class=\"uri\">https:\/\/blog.csdn.net\/julialove102123\/article\/details\/78405284<\/a>. 2017<\/p>\n<p><\/font><\/p>\n<\/div>\n\n\n\n<\/div>\n<\/div>\n\n<\/div>\n\n<script>\n\n\/\/ add bootstrap table styles to pandoc tables\nfunction bootstrapStylePandocTables() {\n $('tr.header').parent('thead').parent('table').addClass('table table-condensed');\n}\n$(document).ready(function () {\n bootstrapStylePandocTables();\n});\n\n\n<\/script>\n\n\n<script>\n (function () {\n var script = document.createElement(\"script\");\n script.type = \"text\/javascript\";\n script.src = \"https:\/\/mathjax.rstudio.com\/latest\/MathJax.js?config=TeX-AMS-MML_HTMLorMML\";\n document.getElementsByTagName(\"head\")[0].appendChild(script);\n })();\n<\/script>\n\n<\/body>\n<\/html>\n\n","protected":false},"excerpt":{"rendered":"<p>\u968f\u673a\u68ee\u6797 Code Show All C […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_uag_custom_page_level_css":"","site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"full-width-container","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"default","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"var(--ast-global-color-4)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""}},"footnotes":""},"categories":[7],"tags":[12,10],"class_list":["post-371","post","type-post","status-publish","format-standard","hentry","category-7","tag-12","tag-10"],"acf":[],"jetpack_featured_media_url":"","uagb_featured_image_src":{"full":false,"thumbnail":false,"medium":false,"medium_large":false,"large":false,"1536x1536":false,"2048x2048":false},"uagb_author_info":{"display_name":"wtxiong","author_link":"https:\/\/byecampus.com\/index.php\/author\/wtxiong\/"},"uagb_comment_info":0,"uagb_excerpt":"\u968f\u673a\u68ee\u6797 Code Show All C 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{"id":371,"date":"2024-03-08T21:00:24","date_gmt":"2024-03-08T13:00:24","guid":{"rendered":"https:\/\/byecampus.com\/?p=371"},"modified":"2024-03-08T21:00:25","modified_gmt":"2024-03-08T13:00:25","slug":"%e9%9a%8f%e6%9c%ba%e6%a3%ae%e6%9e%97","status":"publish","type":"post","link":"https:\/\/byecampus.com\/index.php\/2024\/03\/08\/%e9%9a%8f%e6%9c%ba%e6%a3%ae%e6%9e%97\/","title":{"rendered":"\u968f\u673a\u68ee\u6797"},"content":{"rendered":"\n\n\n\n\n\n\n\n\n\n\n\n\n\n\u968f\u673a\u68ee\u6797<\/title>\n\n<script src=\"1-randomforest_files\/jquery-1.11.3\/jquery.min.js\"><\/script>\n<meta name=\"viewport\" content=\"width=device-width, initial-scale=1\" \/>\n<link href=\"1-randomforest_files\/bootstrap-3.3.5\/css\/united.min.css\" rel=\"stylesheet\" \/>\n<script src=\"1-randomforest_files\/bootstrap-3.3.5\/js\/bootstrap.min.js\"><\/script>\n<script src=\"1-randomforest_files\/bootstrap-3.3.5\/shim\/html5shiv.min.js\"><\/script>\n<script src=\"1-randomforest_files\/bootstrap-3.3.5\/shim\/respond.min.js\"><\/script>\n<script src=\"1-randomforest_files\/jqueryui-1.11.4\/jquery-ui.min.js\"><\/script>\n<link href=\"1-randomforest_files\/tocify-1.9.1\/jquery.tocify.css\" rel=\"stylesheet\" \/>\n<script src=\"1-randomforest_files\/tocify-1.9.1\/jquery.tocify.js\"><\/script>\n<script src=\"1-randomforest_files\/navigation-1.1\/tabsets.js\"><\/script>\n<script src=\"1-randomforest_files\/navigation-1.1\/codefolding.js\"><\/script>\n\n\n<style type=\"text\/css\">code{white-space: pre;}<\/style>\n<style type=\"text\/css\">\ndiv.sourceCode { overflow-x: auto; }\ntable.sourceCode, tr.sourceCode, td.lineNumbers, td.sourceCode {\n margin: 0; padding: 0; vertical-align: baseline; border: none; }\ntable.sourceCode { width: 100%; line-height: 100%; background-color: #f8f8f8; }\ntd.lineNumbers { text-align: right; padding-right: 4px; padding-left: 4px; color: #aaaaaa; border-right: 1px solid #aaaaaa; }\ntd.sourceCode { padding-left: 5px; }\npre, code { background-color: #f8f8f8; }\ncode > span.kw { color: #204a87; font-weight: bold; } \/* Keyword *\/\ncode > span.dt { color: #204a87; } \/* DataType *\/\ncode > span.dv { color: #0000cf; } \/* DecVal *\/\ncode > span.bn { color: #0000cf; } \/* BaseN *\/\ncode > span.fl { color: #0000cf; } \/* Float *\/\ncode > span.ch { color: #4e9a06; } \/* Char *\/\ncode > span.st { color: #4e9a06; } \/* String *\/\ncode > span.co { color: #8f5902; font-style: italic; } \/* Comment *\/\ncode > span.ot { color: #8f5902; } \/* Other *\/\ncode > span.al { color: #ef2929; } \/* Alert *\/\ncode > span.fu { color: #000000; } \/* Function *\/\ncode > span.er { color: #a40000; font-weight: bold; } \/* Error *\/\ncode > span.wa { color: #8f5902; font-weight: bold; font-style: italic; } \/* Warning *\/\ncode > span.cn { color: #000000; } \/* Constant *\/\ncode > span.sc { color: #000000; } \/* SpecialChar *\/\ncode > span.vs { color: #4e9a06; } \/* VerbatimString *\/\ncode > span.ss { color: #4e9a06; } \/* SpecialString *\/\ncode > span.im { } \/* Import *\/\ncode > span.va { color: #000000; } \/* Variable *\/\ncode > span.cf { color: #204a87; font-weight: bold; } \/* ControlFlow *\/\ncode > span.op { color: #ce5c00; font-weight: bold; } \/* Operator *\/\ncode > span.pp { color: #8f5902; font-style: italic; } \/* Preprocessor *\/\ncode > span.ex { } \/* Extension *\/\ncode > span.at { color: #c4a000; } \/* Attribute *\/\ncode > span.do { color: #8f5902; font-weight: bold; font-style: italic; } \/* Documentation *\/\ncode > span.an { color: #8f5902; font-weight: bold; font-style: italic; } \/* Annotation *\/\ncode > span.cv { color: #8f5902; font-weight: bold; font-style: italic; } \/* CommentVar *\/\ncode > span.in { color: #8f5902; font-weight: bold; font-style: italic; } \/* Information *\/\ndiv.sourceCode {\n overflow-x: visible;\n}\n<\/style>\n<style type=\"text\/css\">\n pre:not([class]) {\n background-color: white;\n }\n<\/style>\n\n\n<style type=\"text\/css\">\nh1 {\n font-size: 34px;\n}\nh1.title {\n font-size: 38px;\n}\nh2 {\n font-size: 30px;\n}\nh3 {\n font-size: 24px;\n}\nh4 {\n font-size: 18px;\n}\nh5 {\n font-size: 16px;\n}\nh6 {\n font-size: 12px;\n}\n.table th:not([align]) {\n text-align: left;\n}\n<\/style>\n\n\n<\/head>\n\n<body>\n\n<style type = \"text\/css\">\n.main-container {\n max-width: 940px;\n margin-left: auto;\n margin-right: auto;\n}\ncode {\n color: inherit;\n background-color: rgba(0, 0, 0, 0.04);\n}\nimg {\n max-width:100%;\n height: auto;\n}\n.tabbed-pane {\n padding-top: 12px;\n}\n.html-widget {\n margin-bottom: 20px;\n}\nbutton.code-folding-btn:focus {\n outline: none;\n}\n<\/style>\n\n\n\n<div class=\"container-fluid main-container\">\n\n\n<script>\n$(document).ready(function () {\n window.buildTabsets(\"TOC\");\n});\n<\/script>\n\n\n<style type=\"text\/css\">\n.code-folding-btn { margin-bottom: 4px; }\n<\/style>\n<script>\n$(document).ready(function () {\n window.initializeCodeFolding(\"show\" === \"show\");\n});\n<\/script>\n\n\n\n\n<script>\n$(document).ready(function () {\n\n \/\/ move toc-ignore selectors from section div to header\n $('div.section.toc-ignore')\n .removeClass('toc-ignore')\n .children('h1,h2,h3,h4,h5').addClass('toc-ignore');\n\n \/\/ establish options\n var options = {\n selectors: \"h1,h2,h3\",\n theme: \"bootstrap3\",\n context: '.toc-content',\n hashGenerator: function (text) {\n return text.replace(\/[.\\\\\/?&!#<>]\/g, '').replace(\/\\s\/g, '_').toLowerCase();\n },\n ignoreSelector: \".toc-ignore\",\n scrollTo: 0\n };\n options.showAndHide = true;\n options.smoothScroll = true;\n\n \/\/ tocify\n var toc = $(\"#TOC\").tocify(options).data(\"toc-tocify\");\n});\n<\/script>\n\n<style type=\"text\/css\">\n\n#TOC {\n margin: 25px 0px 20px 0px;\n}\n@media (max-width: 768px) {\n#TOC {\n position: relative;\n width: 100%;\n}\n}\n\n\n.toc-content {\n padding-left: 30px;\n padding-right: 40px;\n}\n\ndiv.main-container {\n max-width: 1200px;\n}\n\ndiv.tocify {\n width: 20%;\n max-width: 260px;\n max-height: 85%;\n}\n\n@media (min-width: 768px) and (max-width: 991px) {\n div.tocify {\n width: 25%;\n }\n}\n\n@media (max-width: 767px) {\n div.tocify {\n width: 100%;\n max-width: none;\n }\n}\n\n.tocify ul, .tocify li {\n line-height: 20px;\n}\n\n.tocify-subheader .tocify-item {\n font-size: 0.90em;\n padding-left: 25px;\n text-indent: 0;\n}\n\n.tocify .list-group-item {\n border-radius: 0px;\n}\n\n\n<\/style>\n\n\n<div class=\"row-fluid\">\n<div class=\"col-xs-12 col-sm-4 col-md-3\">\n<div id=\"TOC\" class=\"tocify\">\n<\/div>\n<\/div>\n\n<div class=\"toc-content col-xs-12 col-sm-8 col-md-9\">\n\n\n\n\n<div class=\"fluid-row\" id=\"header\">\n\n<div class=\"btn-group pull-right\">\n<button type=\"button\" class=\"btn btn-default btn-xs dropdown-toggle\" data-toggle=\"dropdown\" aria-haspopup=\"true\" aria-expanded=\"false\"><span>Code<\/span> <span class=\"caret\"><\/span><\/button>\n<ul class=\"dropdown-menu\" style=\"min-width: 50px;\">\n<li><a id=\"rmd-show-all-code\" href=\"#\">Show All Code<\/a><\/li>\n<li><a id=\"rmd-hide-all-code\" href=\"#\">Hide All Code<\/a><\/li>\n<\/ul>\n<\/div>\n\n\n\n<h1 class=\"title toc-ignore\">\u968f\u673a\u68ee\u6797<\/h1>\n\n<\/div>\n\n\n<div class=\"section level1\">\n<h1><span class=\"header-section-number\">1<\/span> \u968f\u673a\u68ee\u6797\u7b80\u4ecb<\/h1>\n<p><font size=4 face=\"\u5fae\u8f6f\u96c5\u9ed1\"><\/p>\n<hr \/>\n<p>\u2003\u2003\u968f\u673a\u68ee\u6797\u662f\u4e00\u79cd\u6bd4\u8f83\u65b0\u7684\u673a\u5668\u5b66\u4e60\u6a21\u578b\uff0c\u5176\u4e0e\u4e0a\u9762\u6240\u8bb2\u7684k\u8fd1\u90bb\u3001\u6734\u7d20\u8d1d\u53f6\u65af\uff0c\u51b3\u7b56\u6811\u7b49\u8fd9\u4e9b\u7b97\u6cd5\u6700\u5927\u7684\u4e0d\u540c\u4e4b\u5904\u5c31\u662f\u5b83\u662f\u4e00\u79cd\u57fa\u4e8e\u51b3\u7b56\u6811\u7684\u96c6\u6210\u5b66\u4e60\u65b9\u6cd5\uff0c\u5176\u4e2d\u6bcf\u4e00\u9897\u6811\u90fd\u4f9d\u8d56\u4e8e\u4e00\u4e2a\u968f\u673a\u5411\u91cf\uff0c\u68ee\u6797\u4e2d\u6240\u6709\u7684\u5411\u91cf\u90fd\u662f\u72ec\u7acb\u5206\u5e03\u7684\u3002<\/p>\n<p>\u2003\u2003\u968f\u673a\u68ee\u6797\u7684\u5b9e\u8d28\u5c31\u662f\u5bf9\u6570\u636e\u96c6\u7684\u5217\u53d8\u91cf\u548c\u884c\u89c2\u6d4b\u8fdb\u884c\u968f\u673a\u5316\uff0c\u751f\u6210\u591a\u4e2a\u5206\u7c7b\u6570\uff0c\u6700\u7ec8\u5c06\u5206\u7c7b\u6811\u7ed3\u679c\u8fdb\u884c\u6c47\u603b\uff0c\u628a\u6c47\u603b\u540e\u7684\u7ed3\u679c\u4f5c\u4e3a\u6700\u7ec8\u7684\u9884\u6d4b\u7ed3\u679c\u3002<\/p>\n<\/div>\n<div class=\"section level1\">\n<h1><span class=\"header-section-number\">2<\/span> \u968f\u673a\u68ee\u6797\u539f\u7406\u53ca\u4f18\u7f3a\u70b9<\/h1>\n<hr \/>\n<p>\u2003\u2003\u6211\u4eec\u5728\u51b3\u7b56\u6811\u8fd9\u4e00\u8282\u5df2\u7ecf\u4ecb\u7ecd\u4e86\u51b3\u7b56\u6811\u7684\u539f\u7406\uff0c\u968f\u673a\u68ee\u6797\u5c31\u662f\u7531\u591a\u4e2a<strong>\u672a\u526a\u679d<\/strong>\u7684CART\u5206\u7c7b\u51b3\u7b56\u6811\u7ec4\u6210\uff0c\u5176\u4e0d\u4ec5\u53ef\u4ee5\u505a\u56de\u5f52\uff0c\u8fd8\u53ef\u4ee5\u505a\u5206\u7c7b\u3002\u5176\u505a\u56de\u5f52\u65f6\u8fd4\u56de\u7684\u7ed3\u679c\u662f\u5355\u68f5\u6811\u8f93\u51fa\u7ed3\u679c\u7684\u7b80\u5355\u5e73\u5747\uff0c\u505a\u5206\u7c7b\u65f6\u7684\u8fd4\u56de\u7ed3\u679c\u662f\u5355\u68f5\u6811\u8f93\u51fa\u7ed3\u679c\u7684\u4f17\u6570\u3002<\/p>\n<div class=\"section level2\">\n<h2><span class=\"header-section-number\">2.1<\/span> \u6784\u5efa\u6d41\u7a0b<\/h2>\n<p>\u2003\u2003\u968f\u673a\u68ee\u6797\u7684\u6784\u5efa\u6d41\u7a0b\u5e76\u4e0d\u590d\u6742\uff0c\u5176\u4e3b\u8981\u6d41\u7a0b\u5982\u4e0b\uff1a<\/p>\n<ul>\n<li>\u5e94\u7528Bootstrap\u91cd\u91c7\u6837\u65b9\u6cd5\u6709\u653e\u56de\u5730\u968f\u673a\u62bd\u53d6n\u4e2a\u65b0\u7684\u81ea\u52a9\u6837\u672c\u96c6<\/li>\n<li>\u968f\u673a\u4ece\u6240\u6709\u53d8\u91cf\u4e2d\u62bd\u53d6m\u4e2a\u53d8\u91cf\u4f5c\u4e3a\u5b50\u6570\u636e\u96c6\u7684\u53d8\u91cf<\/li>\n<li>\u5bf9k\u4e2a\u542b\u6709m\u4e2a\u53d8\u91cf\u7684\u5b50\u6570\u636e\u96c6\u5206\u522b\u6784\u5efaCART\u6811\uff0c\u5176\u4ed6\u5b50\u6570\u636e\u96c6\u4f5c\u4e3a\u6d4b\u8bd5\u96c6<\/li>\n<li>\u628a\u9700\u8981\u9884\u6d4b\u7684\u6570\u636e\u4ee3\u5165\u751f\u6210\u7684\u591a\u4e2aCART\u6811\uff0c\u6839\u636e\u6bcf\u68f5\u6811\u7684\u6295\u7968\u7ed3\u679c\u53d6\u7968\u6570\u6700\u9ad8\u7684\u4e00\u4e2a\u7c7b\u522b<\/li>\n<\/ul>\n<\/div>\n<div class=\"section level2\">\n<h2><span class=\"header-section-number\">2.2<\/span> \u6027\u80fd<\/h2>\n<ul>\n<li>\u6bcf\u68f5CART\u6811\u751f\u957f\u8d8a\u8302\u76db\uff0c\u7ec4\u6210\u7684\u968f\u673a\u68ee\u6797\u7684\u6027\u80fd\u8d8a\u597d<\/li>\n<li>\u6bcf\u68f5\u6811\u4e4b\u95f4\u72ec\u7acb\u6027\u8d8a\u9ad8\uff0c\u79df\u6210\u7684\u968f\u673a\u68ee\u6797\u7684\u6027\u80fd\u8d8a\u597d<\/li>\n<\/ul>\n<\/div>\n<div class=\"section level2\">\n<h2><span class=\"header-section-number\">2.3<\/span> \u4f18\u7f3a\u70b9<\/h2>\n<hr \/>\n<table>\n<thead>\n<tr class=\"header\">\n<th align=\"left\">\u4f18\u70b9<\/th>\n<th align=\"left\">\u7f3a\u70b9<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr class=\"odd\">\n<td align=\"left\">\u53ef\u4ee5\u9002\u7528\u4e8e\u5927\u591a\u6570\u95ee\u9898\uff0c\u53ef\u5904\u7406\u566a\u58f0\u548c\u7f3a\u5931\u503c\uff1b\u5206\u7c7b\u548c\u8fde\u7eed\u6027\u7279\u5f81\u6570\u636e<\/td>\n<td align=\"left\">\u8bad\u7ec3\u548c\u9884\u6d4b\u6bd4\u8f83\u6162<\/td>\n<\/tr>\n<tr class=\"even\">\n<td align=\"left\">\u4e24\u4e2a\u968f\u673a\u6027\u7684\u5f15\u5165\uff0c\u4f7f\u6a21\u578b\u4e0d\u5bb9\u6613\u8fc7\u62df\u5408<\/td>\n<td align=\"left\">\u5728\u5206\u7c7b\u95ee\u9898\u4e2d\uff0c\u82e5\u76ee\u6807\u6570\u636e\u96c6\u504f\u5c0f\u5e76\u53d8\u91cf\u7c7b\u522b\u8fc7\u591a\uff0c\u5219\u8868\u73b0\u8f83\u5dee<\/td>\n<\/tr>\n<tr class=\"odd\">\n<td align=\"left\">\u5904\u7406\u9ad8\u7ef4\u5ea6\u7684\u6570\u636e\u65f6\uff0c\u53ef\u4ee5\u4e0d\u7528\u505a\u5f88\u8be6\u7ec6\u7684\u5f81\u9009\u62e9<\/td>\n<td align=\"left\"><\/td>\n<\/tr>\n<tr class=\"even\">\n<td align=\"left\">\u5728\u521b\u5efa\u968f\u673a\u68ee\u6797\u7684\u65f6\u5019\uff0c\u5bf9generlization error\u4f7f\u7528\u7684\u662f\u65e0\u504f\u4f30\u8ba1<\/td>\n<td align=\"left\"><\/td>\n<\/tr>\n<tr class=\"odd\">\n<td align=\"left\">\u53ef\u4ee5\u8fd4\u56de\u53d8\u91cf\u7684\u91cd\u8981\u6027<\/td>\n<td align=\"left\"><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<\/div>\n<div class=\"section level1\">\n<h1><span class=\"header-section-number\">3<\/span> \u6848\u4f8b\u5b9e\u6218<\/h1>\n<p>\u2003\u2003\u672c\u6848\u4f8b\u7684\u4e3b\u8981\u5185\u5bb9\u5c31\u662f\u4f7f\u7528\u968f\u673a\u68ee\u6797\u5bf9R\u4e2d\u81ea\u5e26\u7684iris\u6570\u636e\u96c6\u8fdb\u884c\u5206\u7c7b\u3002<\/p>\n<p>\u2003\u2003\u5728R\u4e2d\u5e38\u7528randomforst\u7a0b\u5e8f\u5305\u7684\u5b9e\u73b0\u968f\u673a\u68ee\u6797\u7b97\u6cd5\uff0c\u8be5\u5305\u4e3b\u8981\u6d89\u53ca\u52303\u4e2a\u91cd\u8981\u7684\u51fd\u6570\uff0c\u6bcf\u4e2a\u53c2\u6570\u7684\u8be6\u7ec6\u4fe1\u606f\u8be6\u89c1\u4e0b\u65b9\uff1a<\/p>\n<p><strong>1)randomForest()\u51fd\u6570\u7528\u4e8e\u6784\u5efa\u968f\u673a\u68ee\u6797\u6a21\u578b<\/strong><\/p>\n<p>randomForest(formula, data=NULL, \u2026, subset, na.action=na.fail)<\/p>\n<p>randomForest(x, y=NULL, xtest=NULL, ytest=NULL, ntree=500,<br> \u2003\u2003\u2003\u2003\u2003\u2003\u2003mtry=if (!is.null(y) && !is.factor(y))<br> \u2003\u2003\u2003\u2003\u2003\u2003\u2003max(floor(ncol(x)\/3), 1) else floor(sqrt(ncol(x))),<br> \u2003\u2003\u2003\u2003\u2003\u2003\u2003replace=TRUE, classwt=NULL, cutoff, strata,<br> \u2003\u2003\u2003\u2003\u2003\u2003\u2003sampsize = if (replace) nrow(x) else ceiling(.632*nrow(x)),<br> \u2003\u2003\u2003\u2003\u2003\u2003\u2003nodesize = if (!is.null(y) && !is.factor(y)) 5 else 1,<br> \u2003\u2003\u2003\u2003\u2003\u2003\u2003maxnodes = NULL,<br> \u2003\u2003\u2003\u2003\u2003\u2003\u2003importance=FALSE, localImp=FALSE, nPerm=1,<br> \u2003\u2003\u2003\u2003\u2003\u2003\u2003proximity, oob.prox=proximity,<br> \u2003\u2003\u2003\u2003\u2003\u2003\u2003norm.votes=TRUE, do.trace=FALSE,<br> \u2003\u2003\u2003\u2003\u2003\u2003\u2003keep.forest=!is.null(y) && is.null(xtest), corr.bias=FALSE,<br> \u2003\u2003\u2003\u2003\u2003\u2003\u2003keep.inbag=FALSE, \u2026)<\/p>\n<ul>\n<li><strong>formula\uff1a<\/strong>\u6307\u5b9a\u6a21\u578b\u7684\u516c\u5f0f\u5f62\u5f0f\uff0c\u7c7b\u4f3c\u4e8ey~x1+x2+x3\u2026;<\/li>\n<li><strong>data\uff1a<\/strong>\u6307\u5b9a\u5206\u6790\u7684\u6570\u636e\u96c6\uff1b<\/li>\n<li><strong>subset\uff1a<\/strong>\u4ee5\u5411\u91cf\u7684\u5f62\u5f0f\u786e\u5b9a\u6837\u672c\u6570\u636e\u96c6\uff1b<\/li>\n<li><strong>na.action\uff1a<\/strong>\u6307\u5b9a\u6570\u636e\u96c6\u4e2d\u7f3a\u5931\u503c\u7684\u5904\u7406\u65b9\u6cd5\uff0c\u9ed8\u8ba4\u4e3ana.fail\uff0c\u5373\u4e0d\u5141\u8bb8\u51fa\u73b0\u7f3a\u5931\u503c\uff0c\u4e5f\u53ef\u4ee5\u6307\u5b9a\u4e3ana.omit\uff0c\u5373\u5220\u9664\u7f3a\u5931\u6837\u672c\uff1b<\/li>\n<li><strong>x\uff1a<\/strong>\u6307\u5b9a\u6a21\u578b\u7684\u89e3\u91ca\u53d8\u91cf\uff0c\u53ef\u4ee5\u662f\u77e9\u9635\uff0c\u4e5f\u53ef\u4ee5\u662f\u6570\u636e\u6846\uff1b<\/li>\n<li><strong>y\uff1a<\/strong>\u6307\u5b9a\u6a21\u578b\u7684\u56e0\u53d8\u91cf\uff0c\u53ef\u4ee5\u662f\u79bb\u6563\u7684\u56e0\u5b50\uff0c\u4e5f\u53ef\u4ee5\u662f\u8fde\u7eed\u7684\u6570\u503c\uff0c\u5206\u522b\u5bf9\u5e94\u4e8e\u968f\u673a\u68ee\u6797\u7684\u5206\u7c7b\u6a21\u578b\u548c\u9884\u6d4b\u6a21\u578b\u3002\u8fd9\u91cc\u9700\u8981\u8bf4\u660e\u7684\u662f\uff0c\u5982\u679c\u4e0d\u6307\u5b9ay\u503c\uff0c\u5219\u968f\u673a\u68ee\u6797\u5c06\u662f\u4e00\u4e2a\u65e0\u76d1\u7763\u7684\u6a21\u578b\uff1b <strong>xtest<\/strong>\u548c<strong>ytest<\/strong>\u7528\u4e8e\u9884\u6d4b\u7684\u6d4b\u8bd5\u96c6\uff1b<\/li>\n<li><strong>ntree\uff1a<\/strong>\u6307\u5b9a\u968f\u673a\u68ee\u6797\u6240\u5305\u542b\u7684\u51b3\u7b56\u6811\u6570\u76ee\uff0c\u9ed8\u8ba4\u4e3a500\uff1b<\/li>\n<li><strong>mtry\uff1a<\/strong>\u6307\u5b9a\u8282\u70b9\u4e2d\u7528\u4e8e\u4e8c\u53c9\u6811\u7684\u53d8\u91cf\u4e2a\u6570\uff0c\u9ed8\u8ba4\u60c5\u51b5\u4e0b\u6570\u636e\u96c6\u53d8\u91cf\u4e2a\u6570\u7684\u4e8c\u6b21\u65b9\u6839(\u5206\u7c7b\u6a21\u578b)\u6216\u4e09\u5206\u4e4b\u4e00(\u9884\u6d4b\u6a21\u578b)\u3002\u4e00\u822c\u662f\u9700\u8981\u8fdb\u884c\u4eba\u4e3a\u7684\u9010\u6b21\u6311\u9009\uff0c\u786e\u5b9a\u6700\u4f73\u7684m\u503c\uff1b<\/li>\n<li><strong>replace\uff1a<\/strong>\u6307\u5b9aBootstrap\u968f\u673a\u62bd\u6837\u7684\u65b9\u5f0f\uff0c\u9ed8\u8ba4\u4e3a\u6709\u653e\u56de\u7684\u62bd\u6837\uff1b<\/li>\n<li><strong>classwt\uff1a<\/strong>\u6307\u5b9a\u5206\u7c7b\u6c34\u5e73\u7684\u6743\u91cd\uff0c\u5bf9\u4e8e\u56de\u5f52\u6a21\u578b\uff0c\u8be5\u53c2\u6570\u65e0\u6548\uff1b<\/li>\n<li><strong>strata\uff1a<\/strong>\u4e3a\u56e0\u5b50\u5411\u91cf\uff0c\u7528\u4e8e\u5206\u5c42\u62bd\u6837\uff1b<\/li>\n<li><strong>sampsize\uff1a<\/strong>\u7528\u4e8e\u6307\u5b9a\u6837\u672c\u5bb9\u91cf\uff0c\u4e00\u822c\u4e0e\u53c2\u6570strata\u8054\u5408\u4f7f\u7528\uff0c\u6307\u5b9a\u5206\u5c42\u62bd\u6837\u4e2d\u5c42\u7684\u6837\u672c\u91cf\uff1b<\/li>\n<li><strong>nodesize\uff1a<\/strong>\u6307\u5b9a\u51b3\u7b56\u6811\u8282\u70b9\u7684\u6700\u5c0f\u4e2a\u6570\uff0c\u9ed8\u8ba4\u60c5\u51b5\u4e0b\uff0c\u5224\u522b\u6a21\u578b\u4e3a1\uff0c\u56de\u5f52\u6a21\u578b\u4e3a5\uff1b<\/li>\n<li><strong>maxnodes\uff1a<\/strong>\u6307\u5b9a\u51b3\u7b56\u6811\u8282\u70b9\u7684\u6700\u5927\u4e2a\u6570\uff1b<\/li>\n<li><strong>importance\uff1a<\/strong>\u903b\u8f91\u53c2\u6570\uff0c\u662f\u5426\u8ba1\u7b97\u5404\u4e2a\u53d8\u91cf\u5728\u6a21\u578b\u4e2d\u7684\u91cd\u8981\u6027\uff0c\u9ed8\u8ba4\u4e0d\u8ba1\u7b97\uff0c\u8be5\u53c2\u6570\u4e3b\u8981\u7ed3\u5408importance()\u51fd\u6570\u4f7f\u7528\uff1b<\/li>\n<li><strong>proximity\uff1a<\/strong>\u903b\u8f91\u53c2\u6570\uff0c\u662f\u5426\u8ba1\u7b97\u6a21\u578b\u7684\u4e34\u8fd1\u77e9\u9635\uff0c\u4e3b\u8981\u7ed3\u5408MDSplot()\u51fd\u6570\u4f7f\u7528\uff1b<\/li>\n<li><strong>oob.prox\uff1a<\/strong>\u662f\u5426\u57fa\u4e8eOOB\u6570\u636e\u8ba1\u7b97\u4e34\u8fd1\u77e9\u9635\uff1b<\/li>\n<li><strong>norm.votes\uff1a<\/strong>\u663e\u793a\u6295\u7968\u683c\u5f0f\uff0c\u9ed8\u8ba4\u4ee5\u767e\u5206\u6bd4\u7684\u5f62\u5f0f\u5c55\u793a\u6295\u7968\u7ed3\u679c\uff0c\u4e5f\u53ef\u4ee5\u91c7\u7528\u7edd\u5bf9\u6570\u7684\u5f62\u5f0f\uff1b<\/li>\n<li><strong>do.trace\uff1a<\/strong>\u662f\u5426\u8f93\u51fa\u66f4\u8be6\u7ec6\u7684\u968f\u673a\u68ee\u6797\u6a21\u578b\u8fd0\u884c\u8fc7\u7a0b\uff0c\u9ed8\u8ba4\u4e0d\u8f93\u51fa\uff1b<\/li>\n<li><strong>keep.forest\uff1a<\/strong>\u662f\u5426\u4fdd\u7559\u6a21\u578b\u7684\u8f93\u51fa\u5bf9\u8c61\uff0c\u5bf9\u4e8e\u7ed9\u5b9axtest\u503c\u540e\uff0c\u9ed8\u8ba4\u5c06\u4e0d\u4fdd\u7559\u7b97\u6cd5\u7684\u8fd0\u7b97\u7ed3\u679c\u3002<\/li>\n<\/ul>\n<p><strong>2)importance()\u51fd\u6570\u7528\u4e8e\u8ba1\u7b97\u6a21\u578b\u53d8\u91cf\u7684\u91cd\u8981\u6027<\/strong><\/p>\n<p>importance(x, type=NULL, class=NULL, scale=TRUE, \u2026)<\/p>\n<ul>\n<li><strong>x\uff1a<\/strong>\u4e3arandomForest\u5bf9\u8c61\uff1b<\/li>\n<li><strong>type\u201d<\/strong>\u53ef\u4ee5\u662f1\uff0c\u4e5f\u53ef\u4ee5\u662f2\uff0c\u7528\u4e8e\u5224\u522b\u8ba1\u7b97\u53d8\u91cf\u91cd\u8981\u6027\u7684\u65b9\u6cd5\uff0c1\u8868\u793a\u4f7f\u7528\u7cbe\u5ea6\u5e73\u5747\u8f83\u5c11\u503c\u4f5c\u4e3a\u5ea6\u91cf\u6807\u51c6\uff1b2\u8868\u793a\u91c7\u7528\u8282\u70b9\u4e0d\u7eaf\u5ea6\u7684\u5e73\u5747\u51cf\u5c11\u503c\u6700\u4e3a\u5ea6\u91cf\u6807\u51c6\u3002\u503c\u8d8a\u5927\u8bf4\u660e\u53d8\u91cf\u7684\u91cd\u8981\u6027\u8d8a\u5f3a\uff1b<\/li>\n<li><strong>scale\uff1a<\/strong>\u9ed8\u8ba4\u5bf9\u53d8\u91cf\u7684\u91cd\u8981\u6027\u503c\u8fdb\u884c\u6807\u51c6\u5316\u3002<\/li>\n<\/ul>\n<p><strong>3)MDSplot()\u7ed8\u5236\u5efa\u7acb\u6a21\u578b\u8fc7\u7a0b\u4e2d\u4ea7\u751f\u7684\u4e34\u8fd1\u77e9\u9635\u7ecf\u8fc7\u6807\u51c6\u5316\u540e\u7684\u5750\u6807\u56fe\uff0c\u5c31\u662f\u53ef\u4ee5\u5c06\u9ad8\u4f4d\u56fe\u7f29\u653e\u5230\u4efb\u610f\u5c0f\u7684\u7ef4\u5ea6\u4e0b\u6765\u89c2\u770b\u6a21\u578b\u5404\u4e2a\u7c7b\u522b\u5728\u4e0d\u540c\u7ef4\u5ea6\u4e0b\u7684\u5206\u5e03\u60c5\u51b5<\/strong><\/p>\n<p>MDSplot(rf, fac, k=2, palette=NULL, pch=20, \u2026)<\/p>\n<ul>\n<li><strong>rf\uff1a<\/strong>\u4e3arandomForest\u5bf9\u8c61\uff0c\u9700\u8981\u8bf4\u660e\u7684\u662f\uff0c\u5728\u6784\u5efa\u968f\u673a\u68ee\u6797\u6a21\u578b\u65f6\u5fc5\u987b\u6307\u5b9a\u8ba1\u7b97\u4e34\u8fd1\u77e9\u9635\uff0c\u5373\u8bbe\u7f6eproximity\u53c2\u6570\u4e3aTRUE\uff1b<\/li>\n<li><strong>fac\uff1a<\/strong>\u6307\u5b9a\u968f\u673a\u68ee\u6797\u6a21\u578b\u4e2d\u6240\u4f7f\u7528\u5230\u7684\u56e0\u5b50\u5411\u91cf(\u56e0\u53d8\u91cf)\uff1b<\/li>\n<li><strong>palette\uff1a<\/strong>\u6307\u5b9a\u6240\u7ed8\u56fe\u5f62\u4e2d\u5404\u4e2a\u7c7b\u522b\u7684\u989c\u8272\uff1b<\/li>\n<li><strong>pch\uff1a<\/strong>\u6307\u5b9a\u6240\u7ed8\u56fe\u5f62\u4e2d\u5404\u4e2a\u7c7b\u522b\u5f62\u72b6\uff1b<\/li>\n<\/ul>\n<p><strong>4)rfImpute()\u51fd\u6570\u53ef\u4e3a\u5b58\u5728\u7f3a\u5931\u503c\u7684\u6570\u636e\u96c6\u8fdb\u884c\u63d2\u8865(\u968f\u673a\u68ee\u6797\u6cd5)\uff0c\u5f97\u5230\u6700\u4f18\u7684\u6837\u672c\u62df\u5408\u503c<\/strong><\/p>\n<p>rfImpute(x, y, iter=5, ntree=300, \u2026)<\/p>\n<p>rfImpute(x, data, \u2026, subset)<\/p>\n<ul>\n<li><strong>x\uff1a<\/strong>\u4e3a\u5b58\u5728\u7f3a\u5931\u503c\u7684\u6570\u636e\u96c6\uff1b<\/li>\n<li><strong>y\uff1a<\/strong>\u4e3a\u56e0\u53d8\u91cf\uff0c\u4e0d\u53ef\u4ee5\u5b58\u5728\u7f3a\u5931\u60c5\u51b5\uff1b<\/li>\n<li><strong>iter\uff1a<\/strong>\u6307\u5b9a\u63d2\u503c\u8fc7\u7a0b\u4e2d\u8fed\u4ee3\u6b21\u6570\uff1b<\/li>\n<li><strong>ntree\uff1a<\/strong>\u6307\u5b9a\u6bcf\u6b21\u8fed\u4ee3\u751f\u6210\u7684\u968f\u673a\u68ee\u6797\u4e2d\u51b3\u7b56\u6811\u6570\u91cf\uff1b<\/li>\n<li><strong>subset\uff1a<\/strong>\u4ee5\u5411\u91cf\u7684\u5f62\u5f0f\u6307\u5b9a\u6837\u672c\u96c6\u3002<\/li>\n<\/ul>\n<p><strong>5)treesize()\u51fd\u6570\u7528\u4e8e\u8ba1\u7b97\u968f\u673a\u68ee\u6797\u4e2d\u6bcf\u68f5\u6811\u7684\u8282\u70b9\u4e2a\u6570<\/strong><\/p>\n<p>treesize(x, terminal=TRUE)<\/p>\n<ul>\n<li><strong>x\uff1a<\/strong>\u4e3arandomForest\u5bf9\u8c61\uff1b<\/li>\n<li><strong>terminal\uff1a<\/strong>\u6307\u5b9a\u8ba1\u7b97\u8282\u70b9\u6570\u76ee\u7684\u65b9\u5f0f\uff0c\u9ed8\u8ba4\u53ea\u8ba1\u7b97\u6bcf\u68f5\u6811\u7684\u6839\u8282\u70b9\uff0c\u8bbe\u7f6e\u4e3aFALSE\u65f6\u5c06\u8ba1\u7b97\u6240\u6709\u8282\u70b9(\u6839\u8282\u70b9+\u53f6\u8282\u70b9)\u3002<\/li>\n<\/ul>\n<hr \/>\n<div class=\"section level2\">\n<h2><span class=\"header-section-number\">3.1<\/span> \u83b7\u53d6\u5e76\u63a2\u7d22\u6570\u636e<\/h2>\n<div class=\"sourceCode\"><pre class=\"sourceCode r\"><code class=\"sourceCode r\">mydata <-<span class=\"st\"> <\/span>iris\n<span class=\"kw\">str<\/span>(mydata)<\/code><\/pre><\/div>\n<pre><code>## 'data.frame': 150 obs. of 5 variables:\n## $ Sepal.Length: num 5.1 4.9 4.7 4.6 5 5.4 4.6 5 4.4 4.9 ...\n## $ Sepal.Width : num 3.5 3 3.2 3.1 3.6 3.9 3.4 3.4 2.9 3.1 ...\n## $ Petal.Length: num 1.4 1.4 1.3 1.5 1.4 1.7 1.4 1.5 1.4 1.5 ...\n## $ Petal.Width : num 0.2 0.2 0.2 0.2 0.2 0.4 0.3 0.2 0.2 0.1 ...\n## $ Species : Factor w\/ 3 levels "setosa","versicolor",..: 1 1 1 1 1 1 1 1 1 1 ...<\/code><\/pre>\n<div class=\"sourceCode\"><pre class=\"sourceCode r\"><code class=\"sourceCode r\"><span class=\"kw\">summary<\/span>(mydata)<\/code><\/pre><\/div>\n<pre><code>## Sepal.Length Sepal.Width Petal.Length Petal.Width \n## Min. :4.300 Min. :2.000 Min. :1.000 Min. :0.100 \n## 1st Qu.:5.100 1st Qu.:2.800 1st Qu.:1.600 1st Qu.:0.300 \n## Median :5.800 Median :3.000 Median :4.350 Median :1.300 \n## Mean :5.843 Mean :3.057 Mean :3.758 Mean :1.199 \n## 3rd Qu.:6.400 3rd Qu.:3.300 3rd Qu.:5.100 3rd Qu.:1.800 \n## Max. :7.900 Max. :4.400 Max. :6.900 Max. :2.500 \n## Species \n## setosa :50 \n## versicolor:50 \n## virginica :50 \n## \n## \n## <\/code><\/pre>\n<p>\u2003\u2003\u4ece\u4e0a\u8ff0\u7b80\u5355\u7684\u6570\u636e\u63a2\u7d22\u4e2d\u53d1\u73b0\uff0c\u6570\u636e\u4e00\u5171\u4e94\u5217\u3002\u5176\u4e2d\u56db\u5217\u662f\u6570\u503c\u578b\uff0c\u4e00\u5217\u662f\u56e0\u5b50\u578b\uff0c\u5e76\u4e14\u56e0\u5b50\u578b\u53d8\u91cf\u7684\u56e0\u5b50\u6c34\u5e73\u4e00\u81f4\uff0c\u6bcf\u4e2a\u6c34\u5e73\u7684\u89c2\u6d4b\u5747\u662f50\u4e2a\u3002<\/p>\n<\/div>\n<div class=\"section level2\">\n<h2><span class=\"header-section-number\">3.2<\/span> \u5206\u5c42\u62bd\u6837<\/h2>\n<p>\u2003\u2003\u5206\u5c42\u62bd\u6837\uff0c\u53c8\u79f0\u5206\u7ec4\u62bd\u6837\u3002\u662f\u4e00\u79cd\u6bd4SRS\u66f4\u7cbe\u51c6\u7684\u968f\u673a\u62bd\u6837\u6cd5\uff0c\u6240\u7528\u7684\u65b9\u6cd5\u662f\u8ddf\u636e\u6211\u4eec\u7684\u7814\u7a76\u6027\u8d28\uff0c\u4f9d\u7167\u76f8\u5173\u7684\u6761\u4ef6\u628a\u6bcd\u7fa4\u4f53\u4e2d\u7684\u4e2a\u4f53\u5206\u6210\u4e0d\u540c\u7684\u5c42\u522b\u6216\u7ec4\u522b(strata)\uff0c\u518d\u5206\u522b\u4ece\u6bcf\u4e00\u5c42\u522b\u6216\u7ec4\u522b\u4e2d\u7684\u4e2a\u4f53\u968f\u673a\u62bd\u51fa\u4e00\u5b9a\u7684\u4e2a\u4f53\u6765\u7ec4\u6210\u6837\u672c\u3002<\/p>\n<p>\u2003\u2003\u5728caret\u7a0b\u5e8f\u5305\u4e2d\u63d0\u4f9b\u4e86\u4e00\u79cd\u975e\u5e38\u65b9\u4fbf\u7684\u5206\u5c42\u62bd\u6837\u51fd\u6570<strong>createDataPartition()<\/strong>\uff0c\u4e0b\u9762\u662f\u8be5\u51fd\u6570\u7684\u53c2\u6570\u89e3\u91ca\uff1a<\/p>\n<p>createDataPartition(y, times = 1, p = 0.5, list = TRUE, groups = min(5, length(y)))<\/p>\n<ul>\n<li><strong>y\uff1a<\/strong>\u6307\u5b9a\u6570\u636e\u96c6\u4e2d\u7684\u8f93\u51fa\u53d8\u91cf<\/li>\n<li><strong>times\uff1a<\/strong>\u6307\u5b9a\u521b\u5efa\u7684\u6837\u672c\u4e2a\u6570\uff0c\u9ed8\u8ba4\u7b80\u5355\u968f\u673a\u62bd\u53d6\u4e00\u7ec4\u6837\u672c<\/li>\n<li><strong>p\uff1a<\/strong>\u6307\u5b9a\u6570\u636e\u96c6\u4e2d\u7528\u4e8e\u8bad\u7ec3\u96c6\u7684\u6bd4\u4f8b<\/li>\n<li><strong>list\uff1a<\/strong>\u662f\u5426\u5df2\u5217\u8868\u6216\u77e9\u9635\u7684\u5f62\u5f0f\u5b58\u50a8\u968f\u673a\u62bd\u53d6\u7684\u7d22\u5f15\u53f7\uff0c\u9ed8\u8ba4\u4e3aTRUE<\/li>\n<li><strong>groups\uff1a<\/strong>\u5982\u679c\u8f93\u51fa\u53d8\u91cf\u4e3a\u6570\u503c\u578b\u6570\u636e\uff0c\u5219\u9ed8\u8ba4\u6309\u5206\u4f4d\u6570\u5206\u7ec4\u8fdb\u884c\u53d6\u6837<\/li>\n<\/ul>\n<div class=\"sourceCode\"><pre class=\"sourceCode r\"><code class=\"sourceCode r\"><span class=\"co\"># install.packages("caret")<\/span>\n<span class=\"kw\">library<\/span>(caret)\n\n<span class=\"kw\">set.seed<\/span>(<span class=\"dv\">45<\/span>)\nidx <-<span class=\"st\"> <\/span><span class=\"kw\">createDataPartition<\/span>(<span class=\"dt\">y =<\/span> mydata$Species, <span class=\"dt\">p =<\/span> <span class=\"fl\">0.7<\/span>, <span class=\"dt\">list =<\/span> F)\n\ntrainset <-<span class=\"st\"> <\/span>mydata[idx, ]\ntestset <-<span class=\"st\"> <\/span>mydata[-idx, ]\n\n<span class=\"kw\">prop.table<\/span>(<span class=\"kw\">table<\/span>(mydata$Species)) <span class=\"co\"># \u8ba1\u7b97\u539f\u6570\u636e\u96c6\u4e2dSpecies\u7684\u5360\u6bd4<\/span><\/code><\/pre><\/div>\n<pre><code>## \n## setosa versicolor virginica \n## 0.3333333 0.3333333 0.3333333<\/code><\/pre>\n<div class=\"sourceCode\"><pre class=\"sourceCode r\"><code class=\"sourceCode r\"><span class=\"kw\">prop.table<\/span>(<span class=\"kw\">table<\/span>(trainset$Species)) <span class=\"co\"># \u8ba1\u7b97\u8bad\u7ec3\u96c6\u4e2dSpecies\u7684\u5360\u6bd4<\/span><\/code><\/pre><\/div>\n<pre><code>## \n## setosa versicolor virginica \n## 0.3333333 0.3333333 0.3333333<\/code><\/pre>\n<div class=\"sourceCode\"><pre class=\"sourceCode r\"><code class=\"sourceCode r\"><span class=\"kw\">prop.table<\/span>(<span class=\"kw\">table<\/span>(testset$Species)) <span class=\"co\"># \u8ba1\u7b97\u6d4b\u8bd5\u96c6\u4e2dSpecies\u7684\u5360\u6bd4<\/span><\/code><\/pre><\/div>\n<pre><code>## \n## setosa versicolor virginica \n## 0.3333333 0.3333333 0.3333333<\/code><\/pre>\n<p>\u2003\u2003\u901a\u8fc7\u5206\u5c42\u62bd\u6837\uff0c\u6211\u4eec\u628a\u6570\u636e\u62c6\u5206\u4e3a\u4e86\u8bad\u7ec3\u96c6\u548c\u6d4b\u8bd5\u96c6\uff0c\u5e76\u8ba1\u7b97\u5176\u5bf9\u5e94\u7684\u56e0\u53d8\u91cf\u7684\u6bd4\u4f8b\uff0c\u53d1\u73b0\u6bcf\u4e2a\u6570\u636e\u96c6\u4e2d\u5404\u4e2a\u7c7b\u522b\u7684\u6bd4\u4f8b\u5747\u662f0.33\uff0c\u8bf4\u660e\u8fbe\u5230\u4e86\u5206\u5c42\u62bd\u6837\u7684\u76ee\u7684\u3002<\/p>\n<\/div>\n<div class=\"section level2\">\n<h2><span class=\"header-section-number\">3.3<\/span> \u8bad\u7ec3\u6a21\u578b<\/h2>\n<p>\u2003\u2003\u6211\u4eec\u4f7f\u7528\u4e0a\u9762\u63d0\u5230\u7684<strong>randomForest()<\/strong>\u51fd\u6570\u5bf9\u8bad\u7ec3\u96c6\u8bad\u7ec3\u6a21\u578b\uff0c\u8bbe\u7f6e\u968f\u673a\u53d8\u91cf\u7684\u4e2a\u6570\u4e3a3\uff0c\u6811\u7684\u4e2a\u6570\u4e3a30\uff0c\u5e76\u4e14\u8ba1\u7b97\u5176\u53d8\u91cf\u91cd\u8981\u6027\u3002<\/p>\n<div class=\"sourceCode\"><pre class=\"sourceCode r\"><code class=\"sourceCode r\"><span class=\"co\"># install.packages("randomForest")<\/span>\n<span class=\"kw\">library<\/span>(randomForest)\n\n<span class=\"kw\">set.seed<\/span>(<span class=\"dv\">45<\/span>)\nrf <-<span class=\"st\"> <\/span><span class=\"kw\">randomForest<\/span>(Species ~., <span class=\"dt\">data =<\/span> trainset, <span class=\"dt\">mtry =<\/span> <span class=\"dv\">3<\/span>, <span class=\"dt\">ntree =<\/span> <span class=\"dv\">30<\/span>, <span class=\"dt\">importance =<\/span> T)<\/code><\/pre><\/div>\n<\/div>\n<div class=\"section level2\">\n<h2><span class=\"header-section-number\">3.4<\/span> \u5c55\u793a\u53d8\u91cf\u91cd\u8981\u6027<\/h2>\n<div class=\"sourceCode\"><pre class=\"sourceCode r\"><code class=\"sourceCode r\">imp <-<span class=\"st\"> <\/span><span class=\"kw\">importance<\/span>(<span class=\"dt\">x =<\/span> rf) <span class=\"co\"># \u8ba1\u7b97\u53d8\u91cf\u91cd\u8981\u6027<\/span>\nimp<\/code><\/pre><\/div>\n<pre><code>## setosa versicolor virginica MeanDecreaseAccuracy\n## Sepal.Length 0.000000 2.659596 1.428697 3.458823\n## Sepal.Width 0.000000 0.000000 2.127039 2.045518\n## Petal.Length 4.705308 6.126779 5.735264 6.413416\n## Petal.Width 6.510190 10.718260 11.020814 10.340348\n## MeanDecreaseGini\n## Sepal.Length 1.118633\n## Sepal.Width 1.261948\n## Petal.Length 24.540647\n## Petal.Width 42.307979<\/code><\/pre>\n<div class=\"sourceCode\"><pre class=\"sourceCode r\"><code class=\"sourceCode r\"><span class=\"kw\">varImpPlot<\/span>(rf) <span class=\"co\"># \u5c55\u793a\u53d8\u91cf\u91cd\u8981\u6027<\/span><\/code><\/pre><\/div>\n<p><img decoding=\"async\" src=\"1-randomforest_files\/figure-html\/unnamed-chunk-4-1.png\" width=\"672\" \/><\/p>\n<p>\u2003\u2003\u4e0a\u9762\u4f7f\u7528MeanDecreaseAccuracy\u548cMeanDecreaseGini\u4e24\u79cd\u6307\u6807\u8861\u91cf\u4e86\u5404\u4e2a\u53d8\u91cf\u7684\u91cd\u8981\u6027\uff0c\u53d1\u73b0\u6700\u91cd\u8981\u7684\u662fPatal.Width\uff0c\u5176\u6b21\u662fPatal.Length\u8fd9\u4e24\u4e2a\u53d8\u91cf\uff0c\u4ece\u4e00\u5b9a\u7a0b\u5ea6\u4e0a\u4e5f\u8bf4\u660e\u4e86\u9e22\u5c3e\u82b1\u7684\u5206\u7c7b\u4e0e\u82b1\u74e3\u6709\u6bd4\u8f83\u5927\u7684\u5173\u7cfb\u3002<\/p>\n<\/div>\n<div class=\"section level2\">\n<h2><span class=\"header-section-number\">3.5<\/span> \u9884\u6d4b\u4e14\u8bc4\u4f30<\/h2>\n<div class=\"sourceCode\"><pre class=\"sourceCode r\"><code class=\"sourceCode r\">pred <-<span class=\"st\"> <\/span><span class=\"kw\">predict<\/span>(rf, testset[-<span class=\"dv\">5<\/span>]) <span class=\"co\"># \u5bf9\u6d4b\u8bd5\u96c6\u8fdb\u884c\u9884\u6d4b<\/span>\n<span class=\"kw\">table<\/span>(pred, testset$Species)<\/code><\/pre><\/div>\n<pre><code>## \n## pred setosa versicolor virginica\n## setosa 15 0 0\n## versicolor 0 15 1\n## virginica 0 0 14<\/code><\/pre>\n<p>\u2003\u2003\u4ece\u6df7\u6dc6\u77e9\u9635\u4e2d\u53ef\u4ee5\u770b\u51fa\uff0c\u4ec5\u6709\u4e00\u4e2a\u6837\u672c\u88ab\u9884\u6d4b\u9519\u8bef(\u4e00\u4e2avirginica\u7684\u9e22\u5c3e\u82b1\u88ab\u9519\u8bef\u7684\u5206\u7c7b\u4e3a\u4e86versicolor)\uff0c\u6539\u6a21\u578b\u7684\u5206\u7c7b\u6548\u679c\u8fd8\u662f\u975e\u5e38\u597d\u7684\u3002<\/p>\n<\/div>\n<\/div>\n<div class=\"section level1\">\n<h1><span class=\"header-section-number\">4<\/span> \u53c2\u8003\u6587\u732e<\/h1>\n<hr \/>\n<p>[1] \u5361\u5df4\u79d1\u5f17. R\u8bed\u8a00\u5b9e\u6218[M]. \u4eba\u6c11\u90ae\u7535\u51fa\u7248\u793e, 2013.<br> [2] \u673a\u5668\u5b66\u4e60\u2014\u2014\u968f\u673a\u68ee\u6797\u7b97\u6cd5\u53ca\u539f\u7406. <a href=\"https:\/\/blog.csdn.net\/nieson2012\/article\/details\/51279332v\" class=\"uri\">https:\/\/blog.csdn.net\/nieson2012\/article\/details\/51279332v<\/a>. 2016.<br> [3] \u6559\u4f60\u4f7f\u7528caret\u5305(\u4e00)\u2013\u6570\u636e\u9884\u5904\u7406. <a href=\"https:\/\/mp.weixin.qq.com\/s\/EXq9B-imnX6D27okYvPGkw\" class=\"uri\">https:\/\/mp.weixin.qq.com\/s\/EXq9B-imnX6D27okYvPGkw<\/a>. 2016<br> [4] \u57fa\u4e8eR\u8bed\u8a00\u7684\u968f\u673a\u68ee\u6797\u7b97\u6cd5\u8fd0\u7528. <a href=\"https:\/\/mp.weixin.qq.com\/s?__biz=MzIxNjA2ODUzNg\" class=\"uri\">https:\/\/mp.weixin.qq.com\/s?__biz=MzIxNjA2ODUzNg<\/a>==&mid=400806663&idx=1&sn=51b4b7a44a33606bd9262e208f91c2df&mpshare=1&scene=23&srcid=0621JANvo04Zy7uaMQt5kxbg#rd. 2015<br> [6] \u673a\u5668\u5b66\u4e60\u5341\u5927\u7b97\u6cd5\u20148. \u968f\u673a\u68ee\u6797\u7b97\u6cd5. <a href=\"https:\/\/blog.csdn.net\/julialove102123\/article\/details\/78405284\" class=\"uri\">https:\/\/blog.csdn.net\/julialove102123\/article\/details\/78405284<\/a>. 2017<\/p>\n<p><\/font><\/p>\n<\/div>\n\n\n\n<\/div>\n<\/div>\n\n<\/div>\n\n<script>\n\n\/\/ add bootstrap table styles to pandoc tables\nfunction bootstrapStylePandocTables() {\n $('tr.header').parent('thead').parent('table').addClass('table table-condensed');\n}\n$(document).ready(function () {\n bootstrapStylePandocTables();\n});\n\n\n<\/script>\n\n\n<script>\n (function () {\n var script = document.createElement(\"script\");\n script.type = \"text\/javascript\";\n script.src = \"https:\/\/mathjax.rstudio.com\/latest\/MathJax.js?config=TeX-AMS-MML_HTMLorMML\";\n document.getElementsByTagName(\"head\")[0].appendChild(script);\n })();\n<\/script>\n\n<\/body>\n<\/html>\n\n","protected":false},"excerpt":{"rendered":"<p>\u968f\u673a\u68ee\u6797 Code Show All C […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_uag_custom_page_level_css":"","site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"full-width-container","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"default","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"var(--ast-global-color-4)","background-image":"","background-repeat":"repeat","background-position":"center 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center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-gradient":""}},"footnotes":""},"categories":[7],"tags":[12,10],"class_list":["post-371","post","type-post","status-publish","format-standard","hentry","category-7","tag-12","tag-10"],"acf":[],"jetpack_featured_media_url":"","uagb_featured_image_src":{"full":false,"thumbnail":false,"medium":false,"medium_large":false,"large":false,"1536x1536":false,"2048x2048":false},"uagb_author_info":{"display_name":"wtxiong","author_link":"https:\/\/byecampus.com\/index.php\/author\/wtxiong\/"},"uagb_comment_info":0,"uagb_excerpt":"\u968f\u673a\u68ee\u6797 Code Show All C […]","_links":{"self":[{"href":"https:\/\/byecampus.com\/index.php\/wp-json\/wp\/v2\/posts\/371","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/byecampus.com\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/byecampus.com\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/byecampus.com\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/byecampus.com\/index.php\/wp-json\/wp\/v2\/comments?post=371"}],"version-history":[{"count":1,"href":"https:\/\/byecampus.com\/index.php\/wp-json\/wp\/v2\/posts\/371\/revisions"}],"predecessor-version":[{"id":372,"href":"https:\/\/byecampus.com\/index.php\/wp-json\/wp\/v2\/posts\/371\/revisions\/372"}],"wp:attachment":[{"href":"https:\/\/byecampus.com\/index.php\/wp-json\/wp\/v2\/media?parent=371"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/byecampus.com\/index.php\/wp-json\/wp\/v2\/categories?post=371"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/byecampus.com\/index.php\/wp-json\/wp\/v2\/tags?post=371"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}