{"id":2563,"date":"2021-07-01T11:52:55","date_gmt":"2021-07-01T02:52:55","guid":{"rendered":"https:\/\/sirprize.co.jp\/meo\/?p=2563"},"modified":"2021-07-01T11:52:55","modified_gmt":"2021-07-01T02:52:55","slug":"tf-idf","status":"publish","type":"post","link":"https:\/\/sirprize.co.jp\/meo\/word\/tf-idf\/","title":{"rendered":"TF-IDF"},"content":{"rendered":"<dl class=\"box22\">\n<dt><span class=\"ymarker\">TF-IDF\u3068\u306f<\/span><\/dt>\n<dd style=\"font-size: 75%;margin: 10px 0\">tf-idf\u3068\u306f\u3001\u60c5\u5831\u63a2\u7d22\u3084\u30c6\u30ad\u30b9\u30c8\u30de\u30a4\u30cb\u30f3\u30b0\u306a\u3069\u306e\u5206\u91ce\u3067\u5229\u7528\u3055\u308c\u308b\u3001\u6587\u66f8\u4e2d\u306b\u51fa\u73fe\u3057\u305f\u7279\u5b9a\u306e\u5358\u8a9e\u304c\u3069\u306e\u304f\u3089\u3044\u7279\u5fb4\u7684\u3067\u3042\u308b\u304b\u3092\u8b58\u5225\u3059\u308b\u305f\u3081\u306e\u6307\u6a19\u306e\u3053\u3068\u3067\u3042\u308b\u3002<\/dd>\n<\/dl>\n<hr style=\"border-width: 0.5px 0 0 0;border-style: solid;margin: 10px 0\" \/>\n<dl class=\"box22\">\n<dd style=\"font-size: 80%;margin: 10px 0;font-weight: bold\">&gt;&gt;\u3000MEO\u3067\u306f\u300c\u983b\u51fa\u5358\u8a9e\u306e\u6e2c\u5b9a\u306e\u3053\u3068\u300d\u3092\u6307\u3057\u307e\u3059<\/dd>\n<\/dl>\n<div style=\"text-align: right\"><a style=\"font-size: 60%\" href=\"https:\/\/ja.wikipedia.org\/wiki\/BERT_(%E8%A8%80%E8%AA%9E%E3%83%A2%E3%83%87%E3%83%AB)\" target=\"\" rel=\"noopener\">\u53c2\u8003\uff1a Weblio\u8f9e\u66f8\u300cTF-IDF\u300d<\/a><\/div>\n<div id=\"toc_container\" class=\"toc_transparent no_bullets\"><p class=\"toc_title\">\u30bf\u30c3\u30d7\u3067\u304d\u308b\u898b\u51fa\u3057<\/p><ul class=\"toc_list\"><li><a href=\"#i\">\u7565\u6b74\/\u6d41\u308c<\/a><ul><li><a href=\"#TF-IDF\">TF-IDF\u3068\u306f\uff1f<\/a><\/li><li><a href=\"#TF\">TF\u5024\u306e\u5b9a\u7fa9<\/a><\/li><li><a href=\"#TF-2\">TF\u306e\u8a08\u7b97\u5f0f<\/a><\/li><li><a href=\"#IDF\">IDF\u5024\u306e\u5b9a\u7fa9<\/a><\/li><li><a href=\"#IDF-2\">IDF\u306e\u8a08\u7b97\u5f0f<\/a><\/li><li><a href=\"#TF-IDF-2\">TF-IDF\u5024\u306e\u5b9a\u7fa9<\/a><\/li><li><a href=\"#TF-IDF-3\">TF-IDF\u5024\u306e\u8a08\u7b97\u5f0f<\/a><\/li><li><a href=\"#TF-IDF-4\">TF-IDF\u5024\u306e\u6b20\u70b9<\/a><\/li><\/ul><\/li><li><a href=\"#i-2\">\u95a2\u9023\u3059\u308b\u5358\u8a9e\u306e\u7d39\u4ecb<\/a><ul><li><a href=\"#i-3\">\u81ea\u7136\u8a00\u8a9e\u51e6\u7406<\/a><\/li><li><a href=\"#i-4\">\u6f5c\u5728\u610f\u5473\u89e3\u6790<\/a><\/li><li><a href=\"#Okapi_BM25\">Okapi BM25<\/a><\/li><\/ul><\/li><li><a href=\"#i-5\">\u4e00\u822c\u7684\u306a\u6d3b\u7528\u65b9\u6cd5\u3001\u69d8\u3005\u306a\u76ee\u7dda\u304b\u3089\u7d39\u4ecb<\/a><\/li><li><a href=\"#MEO\">MEO\u306b\u304a\u3051\u308b\u512a\u4f4d\u70b9\u30fb\u30e1\u30ea\u30c3\u30c8\u30fb\u6ce8\u610f\u70b9<\/a><\/li><li><a href=\"#i-6\">\u95a2\u9023\u30ad\u30fc\u30ef\u30fc\u30c9<\/a><\/li><\/ul><\/div>\n<h2><span class=\"ez-toc-section\" id=\"%E7%95%A5%E6%AD%B4%E6%B5%81%E3%82%8C\"><\/span><span id=\"i\"><strong>\u7565\u6b74\/\u6d41\u308c<\/strong><\/span><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p><span class=\"ymarker\"><strong>TF-IDF\u306f1972\u5e74\u306b\u30ab\u30ec\u30f3\u30fb\u30b9\u30d1\u30fc\u30af\u30fb\u30b8\u30e7\u30fc\u30f3\u30ba\u306b\u3088\u3063\u3066\u63d0\u5531\u3055\u308c\u3001\u3053\u306e\u6642\u5f7c\u5973\u306f\u300c\u81ea\u5206\u304c\u3084\u308b\u3053\u3068\u306e\u80cc\u666f\u3084\u52d5\u6a5f\u3001\u6b63\u5f53\u6027\u306b\u3064\u3044\u3066\u8003\u3048\u308b\u5fc5\u8981\u304c\u3042\u308b\u300d\u3068\u8a71\u3057\u3066\u3044\u307e\u3059\u3002<\/strong><\/span><\/p>\n<p><span style=\"font-weight: 400\">\u307e\u305f\u30ab\u30ec\u30f3\u30fb\u30b9\u30d1\u30fc\u30af\u30fb\u30b8\u30e7\u30fc\u30f3\u30ba\u306e\u7814\u7a76\u3067\u306f \u81ea\u7136\u8a00\u8a9e\u51e6\u7406 \u3001 \u60c5\u5831\u691c\u7d22\u305d\u3057\u3066Okapi BM25\u306b\u307e\u3067\u53ca\u3073\u3001\u73fe\u5728\u306e\u30a4\u30f3\u30bf\u30fc\u30cd\u30c3\u30c8\u754c\u306b\u8ca2\u732e\u3057\u3066\u3044\u308b\u3068\u3044\u3048\u308b\u3067\u3057\u3087\u3046\u3002<\/span><\/p>\n<h3><span class=\"ez-toc-section\" id=\"TF-IDF%E3%81%A8%E3%81%AF%EF%BC%9F\"><\/span><span id=\"TF-IDF\">TF-IDF\u3068\u306f\uff1f<\/span><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p><strong>\u6587\u66f8\u306e\u4e2d\u306b\u542b\u307e\u308c\u3066\u3044\u308b\u5358\u8a9e\u306e\u91cd\u8981\u5ea6\u3092\u660e\u3089\u304b\u306b\u3059\u308b\u6a5f\u80fd\u3067\u3042\u308bTF-IDF\u306f\u3001\u30c8\u30d4\u30c3\u30af\u5206\u6790\u3084\u60c5\u5831\u306a\u3069\u306e\u691c\u7d22\u306b\u7528\u3044\u3089\u308c\u308b\u624b\u6cd5\u3067\u3059\u3002<\/strong><\/p>\n<p><span style=\"font-weight: 400\">\u4f8b\u3048\u3070\u6587\u66f8\u304c\u8907\u6570\u3042\u3063\u305f\u6642\u306b\u3001\u305d\u308c\u3089\u306b\u542b\u307e\u308c\u308b\u5358\u8a9e\u3068\u4f7f\u7528\u983b\u5ea6\u3092\u5206\u6790\u3057\u3001\u3042\u308b\u6587\u66f8\u306b\u3068\u3063\u3066\u4f55\u304c\u91cd\u8981\u306a\u5358\u8a9e\u306a\u306e\u304b\u3092\u6570\u5024\u5316\u3057\u305f\u3082\u306e\u3092TF-IDF\u3068\u8a00\u3044\u307e\u3059\u3002<\/span><\/p>\n<p><span class=\"ymarker\"><strong>TF-IDF\u306f\u3001Term Frequency(TF\u5024)\u3068\u3001Inverse Document Frequency(IDF\u5024)\u3092\u7d44\u307f\u5408\u308f\u305b\u305f\u6982\u5ff5\u3067\u3042\u308a\u3001TF\u306f\u300c\u6587\u66f8\u5185\u306b\u304a\u3044\u3066\u5358\u8a9e\u304c\u51fa\u73fe\u3059\u308b\u983b\u5ea6\u300d\u3092\u3001IDF\u306f\u300c\u3042\u308b\u5358\u8a9e\u304c\u51fa\u73fe\u3059\u308b\u6587\u66f8\u983b\u5ea6\u306e\u9006\u6570\u300d\u3092\u610f\u5473\u3057\u307e\u3059\u3002<\/strong><\/span><\/p>\n<h3><span class=\"ez-toc-section\" id=\"TF%E5%80%A4%E3%81%AE%E5%AE%9A%E7%BE%A9\"><\/span><span id=\"TF\"><span style=\"font-weight: 400\">TF\u5024\u306e\u5b9a\u7fa9<\/span><\/span><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p><span style=\"color: #ff0000\"><strong>TF\u5024\u306f\u3001\u6587\u66f8\u5185\u306b\u304a\u3051\u308b\u300c\u3042\u308b\u5358\u8a9e\u306e\u51fa\u73fe\u983b\u5ea6\u300d\u3092\u6307\u3057\u307e\u3059\u3002<\/strong><\/span><\/p>\n<p><span style=\"color: #000000\">\u8981\u306f\u3001\u6587\u66f8\u5185\u306b\u3042\u308b\u5168\u3066\u306e\u5358\u8a9e\u306e\u51fa\u73fe\u56de\u6570\u306b\u5bfe\u3057\u3001\u305d\u306e\u5358\u8a9e\u306e\u51fa\u73fe\u56de\u6570\u304c\u3069\u308c\u307b\u3069\u3092\u5360\u3081\u308b\u304b\u3068\u3044\u3046\u5272\u5408\u3092\u8868\u3059\u3082\u306e\u3068\u7406\u89e3\u3059\u308c\u3070\u3088\u3044\u3067\u3057\u3087\u3046\u3002<\/span><\/p>\n<p><strong>\u305d\u306e\u5358\u8a9e\u306e\u51fa\u73fe\u56de\u6570\u304c\u591a\u3051\u308c\u3070TF\u5024\u306f\u5927\u304d\u304f\u306a\u308a\u3001\u9006\u306b\u51fa\u73fe\u56de\u6570\u304c\u4f4e\u3051\u308c\u3070\u3001TF\u5024\u304c\u4e0b\u304c\u308b\u3057\u304f\u307f\u3067\u3059\u3002<\/strong><\/p>\n<h3><span class=\"ez-toc-section\" id=\"TF%E3%81%AE%E8%A8%88%E7%AE%97%E5%BC%8F\"><\/span><span id=\"TF-2\"><span style=\"font-weight: 400\">TF\u306e\u8a08\u7b97\u5f0f<\/span><\/span><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p><span style=\"font-weight: 400\">\u300c\u3088\u308a\u591a\u304f\u51fa\u3066\u304f\u308b\u5358\u8a9e\u306f\u3001\u3088\u308a\u91cd\u8981\u306a\u5358\u8a9e\u3067\u3042\u308b\u300d\u3068\u3044\u3046\u7406\u8ad6\u306b\u57fa\u3065\u304d\u3001\u300cn\u56de\u51fa\u73fe\u3057\u305f\u8a9e\u306f\u4e00\u56de\u3057\u304b \u51fa\u73fe\u3057\u306a\u3044\u8a9e\u3088\u308a\u3082 log10(n)\uff0b1 \u500d\u91cd\u8981\u300d\u3068\u307f\u306a\u3057\u3001Wij\uff1dtfij\u00d7log ( N\/ dfi )\u3068\u3044\u3046\u8a08\u7b97\u5f0f\u304c\u7528\u3044\u3089\u308c\u307e\u3059\u3002<\/span><\/p>\n<h3><span class=\"ez-toc-section\" id=\"IDF%E5%80%A4%E3%81%AE%E5%AE%9A%E7%BE%A9\"><\/span><span id=\"IDF\"><span style=\"font-weight: 400\">IDF\u5024\u306e\u5b9a\u7fa9<\/span><\/span><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p><strong>IDF\u5024\u306f\u3001\u300c\u6587\u66f8\u96c6\u5408\u4f53\u306e\u4e2d\u306b\u3042\u308b\u5358\u8a9e\u304c\u542b\u307e\u308c\u308b\u6587\u66f8\u306e\u5272\u5408\u306e\u9006\u6570\u300d<\/strong><span style=\"font-weight: 400\"><strong>\u3092\u8868\u3057\u307e\u3059\u3002<\/strong><\/span><\/p>\n<p><span style=\"font-weight: 400\">\u305d\u306e\u5358\u8a9e\u304c\u4ed6\u306e\u6587\u66f8\u4e2d\u3067\u3082\u591a\u304f\u51fa\u73fe\u3057\u3066\u3044\u308c\u3070IDF\u5024\u306f\u5c0f\u3055\u304f\u3001\u4ed6\u306e\u6587\u66f8\u306b\u3042\u307e\u308a\u51fa\u73fe\u3057\u3066\u3044\u306a\u3044\u307b\u3069IDF\u5024\u306f\u5927\u304d\u3044\u3068\u3044\u3046\u3053\u3068\u3067\u3059\u3002<\/span><\/p>\n<h3><span class=\"ez-toc-section\" id=\"IDF%E3%81%AE%E8%A8%88%E7%AE%97%E5%BC%8F\"><\/span><span id=\"IDF-2\"><span style=\"font-weight: 400\">IDF\u306e\u8a08\u7b97\u5f0f<\/span><\/span><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p><span style=\"font-weight: 400\">\u300c\u3042\u308b\u8a9e\u306b\u5bfe\u3057\u3001\u305d\u306e\u8a9e\u304c\u51fa\u73fe\u3059\u308b\u56de\u6570\u304c\u5c11\u306a\u3051\u308c\u3070\u5c11\u306a\u3044\u307b\u3069\u3001\u305d\u306e\u8a9e\u306f\u3088\u308a\u5927\u304d\u306a\u91cd\u307f\u3068\u306a\u308b\u300d\u3068\u3044\u3046\u7406\u8ad6\u306b\u57fa\u3065\u304d\u3001\u300c\u3042\u308b\u8a9e\u306b\u5bfe\u3057\u3066\u767b\u5834\u3059\u308b\u8a9e\u306e\u6587\u66f8\u306e\u6570\u300d\u3092df\u3001\u300c\u6587\u66f8\u304c\u96c6\u5408\u3057\u305f\u5168\u4f53\u306e\u6587\u66f8\u306e\u6570\u300d\u3092N\u3068\u3057\u3001log10(N\/df)\u3068\u3044\u3046\u8a08\u7b97\u5f0f\u304c\u7528\u3044\u3089\u308c\u307e\u3059\u3002<\/span><\/p>\n<h3><span class=\"ez-toc-section\" id=\"TF-IDF%E5%80%A4%E3%81%AE%E5%AE%9A%E7%BE%A9\"><\/span><span id=\"TF-IDF-2\"><span style=\"font-weight: 400\">TF-IDF\u5024\u306e\u5b9a\u7fa9<\/span><\/span><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p><span style=\"font-weight: 400\">TF-IDF\u306e\u8a08\u7b97\u306f\u3001TF\u5024\u3068IDF\u5024\u3092\u304b\u3051\u3042\u308f\u305b\u3066\u884c\u3044\u307e\u3059\u3002<\/span><\/p>\n<p><span style=\"font-weight: 400\">\u4f8b\u3048\u3070\u6587\u66f8A\u3067\u306e\u51fa\u73fe\u56de\u6570\u306f\u591a\u304f\u3066\u4ed6\u306e\u6587\u66f8\u306b\u306f\u51fa\u73fe\u3057\u3066\u3044\u306a\u3044\u5358\u8a9e\u306eTF-IDF\u5024\u306f\u5927\u304d\u304f\u306a\u308a\u3001\u305d\u308c\u4ee5\u5916\u306e\u5358\u8a9e\u306f\u76f8\u5bfe\u7684\u306bTF-IDF\u5024\u304c\u5c0f\u3055\u304f\u306a\u308b\u3068\u3044\u3046\u3053\u3068\u3067\u3059\u3002<\/span><\/p>\n<p><span class=\"ymarker\"><strong>\u3053\u306e\u3088\u3046\u306b\u3001\u7b97\u51fa\u3057\u305fTF\u5024\u3068IDF\u5024\u540c\u58eb\u3092\u304b\u3051\u5408\u308f\u305b\u308b\u3068\u3001\u5358\u8a9e\u3054\u3068\u306b\u91cd\u8981\u5ea6\u3092\u7b97\u51fa\u3067\u304d\u307e\u3059\u3002\u305d\u3057\u3066\u6587\u66f8\u3054\u3068\u3001\u5358\u8a9e\u3054\u3068\u306bTF-IDF\u5024\u304c\u3042\u308b\u306e\u3067\u3059\u3002<\/strong><\/span><\/p>\n<h3><span class=\"ez-toc-section\" id=\"TF-IDF%E5%80%A4%E3%81%AE%E8%A8%88%E7%AE%97%E5%BC%8F\"><\/span><span id=\"TF-IDF-3\"><span style=\"font-weight: 400\">TF-IDF\u5024\u306e\u8a08\u7b97\u5f0f<\/span><\/span><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p><span style=\"font-weight: 400\">TF\u5024\u306e\u8a08\u7b97\u5f0f\u3067\u51fa\u3057\u305f\u3057\u305f\u5024\u3068IDF\u5024\u306e\u8a08\u7b97\u5f0f\u3067\u51fa\u3057\u305f\u5024\u3092\u304b\u3051\u5408\u308f\u305b\u308b\u3068\u3001TF-IDF\u5024\u306e\u8a08\u7b97\u5f0f\u3068\u306a\u308a\u307e\u3059\u3002<\/span><\/p>\n<p><span style=\"font-weight: 400\">ftidf(t1,dj)=tf(ti,df)\u30fbidf(ti)<\/span><\/p>\n<h3><span class=\"ez-toc-section\" id=\"TF-IDF%E5%80%A4%E3%81%AE%E6%AC%A0%E7%82%B9\"><\/span><span id=\"TF-IDF-4\"><span style=\"font-weight: 400\">TF-IDF\u5024\u306e\u6b20\u70b9<\/span><\/span><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p><span style=\"font-weight: 400\">\u6587\u66f8\u5185\u306b\u51fa\u73fe\u3059\u308b\u5358\u8a9e\u6570\u304c\u591a\u3044\u307b\u3069TF\u5024\u306f\u5c0f\u3055\u304f\u306a\u308a\u3001\u9006\u306b\u5358\u8a9e\u6570\u304c\u5c11\u306a\u3044\u307b\u3069TF\u5024\u306f\u5927\u304d\u304f\u306a\u308a\u307e\u3059\u3002\u305d\u306e\u7406\u7531\u306f\u3001\u300cTF\u5024\u306e\u8a08\u7b97\u5f0f\u3067\u7528\u3044\u308b\u5206\u6bcd\u304c\u3001\u300c\u5168\u3066\u306e\u5358\u8a9e\u304c\u51fa\u73fe\u3059\u308b\u56de\u6570\u306e\u548c\u300d\u3092\u3068\u3063\u3066\u3044\u308b\u3053\u3068\u304c\u8981\u56e0\u3067\u3059\u3002<\/span><\/p>\n<p><span class=\"ymarker\"><strong>\u3059\u306a\u308f\u3061\u3001\u8907\u6570\u3042\u308b\u6587\u66f8\u306e\u4e2d\u304b\u3089\u91cd\u8981\u5ea6\u304c\u9ad8\u3044\u5358\u8a9e\u3092\u62bd\u51fa\u3057\u3001TF-IDF\u5024\u3092\u7d76\u5bfe\u8a55\u4fa1\u3067\u6bd4\u8f03\u3059\u308b\u3068\u306a\u308b\u3068\u3001\u6587\u66f8\u3054\u3068\u306b\u542b\u307e\u308c\u308b\u5358\u8a9e\u6570\u306e\u5dee\u304c\u5927\u304d\u304f\u5f71\u97ff\u3057\u3066\u3057\u307e\u3044\u307e\u3059\u3002<\/strong><\/span><\/p>\n<p><span style=\"font-weight: 400\">\u305d\u3053\u3092\u89e3\u6c7a\u3059\u3079\u304f\u3001Stephen E.Robertson\u3001Karen Sp\u00e4rck Jones\u3089\u306b\u3088\u3063\u3066\u63d0\u6848\u3055\u308c\u305f\u306e\u304c\u300cOkapi BM25\u300d\u3068\u3044\u3046\u308f\u3051\u3067\u3059\u3002<\/span><\/p>\n<h2><span class=\"ez-toc-section\" id=\"%E9%96%A2%E9%80%A3%E3%81%99%E3%82%8B%E5%8D%98%E8%AA%9E%E3%81%AE%E7%B4%B9%E4%BB%8B\"><\/span><span id=\"i-2\"><span style=\"font-weight: 400\">\u95a2\u9023\u3059\u308b\u5358\u8a9e\u306e\u7d39\u4ecb<\/span><\/span><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<h3><span class=\"ez-toc-section\" id=\"%E8%87%AA%E7%84%B6%E8%A8%80%E8%AA%9E%E5%87%A6%E7%90%86\"><\/span><span id=\"i-3\"><b>\u81ea\u7136\u8a00\u8a9e\u51e6\u7406<\/b><\/span><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p><span style=\"font-weight: 400\">\u81ea\u7136\u8a00\u8a9e\u51e6\u7406(NPL)\u3068\u306f\u3001\u8a00\u8449\u3084\u6587\u5b57\u3068\u3044\u3063\u305f\u30b3\u30df\u30e5\u30cb\u30b1\u30fc\u30b7\u30e7\u30f3\u3067\u4f7f\u308f\u308c\u308b\u8a71\u3057\u8a00\u8449\u304b\u3089\u66f8\u304d\u8a00\u8449\u307e\u3067\u306e\u81ea\u7136\u306a\u8a00\u8a9e\u3092\u5bfe\u8c61\u306b\u3001\u305d\u308c\u305e\u308c\u304c\u6301\u3064\u826f\u3044\u3084\u5185\u5bb9\u3092\u62bd\u51fa\u30fb\u89e3\u6790\u3059\u308b\u51e6\u7406\u6280\u8853\u306e\u3053\u3068\u3067\u3059\u3002<\/span><\/p>\n<h3><span class=\"ez-toc-section\" id=\"%E6%BD%9C%E5%9C%A8%E6%84%8F%E5%91%B3%E8%A7%A3%E6%9E%90\"><\/span><span id=\"i-4\"><b>\u6f5c\u5728\u610f\u5473\u89e3\u6790<\/b><\/span><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p><span style=\"font-weight: 400\">\u6f5c\u5728\u610f\u5473\u89e3\u6790(LSA)\u3068\u306f\u3001\u3042\u308b\u6587\u7ae0\u7fa4\u306b\u542b\u307e\u308c\u308b\u69d8\u8a9e\u7fa4\u306b\u5bfe\u3057\u3001\u95a2\u9023\u3057\u305f\u6982\u5ff5\u306e\u96c6\u5408\u3092\u751f\u6210\u3057\u3066\u3001\u4e21\u8005\u306e\u95a2\u4fc2\u3092\u5206\u6790\u3059\u308b\u3082\u306e\u3067\u3059\u3002\u30d9\u30af\u30c8\u30eb\u7a7a\u9593\u30e2\u30c7\u30eb\u306b\u3088\u308b\u81ea\u7136\u8a00\u8a9e\u51e6\u7406\u306e\u65b9\u6cd5\u306e1\u3064\u3068\u306a\u308a\u307e\u3059\u3002<\/span><\/p>\n<h3><span class=\"ez-toc-section\" id=\"Okapi_BM25\"><\/span><span id=\"Okapi_BM25\"><b>Okapi BM25<\/b><\/span><span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p><span style=\"font-weight: 400\">Okapi BM25\u306f\u3001\u60c5\u5831\u691c\u7d22\u306e\u4e2d\u3067\u306e\u9806\u4f4d\u4ed8\u3051\u306e\u624b\u6cd5\u3067\u3042\u308a\u3001\u691c\u7d22\u30a8\u30f3\u30b8\u30f3\u304c\u30af\u30a8\u30ea\u3068\u306e\u95a2\u4fc2\u306b\u9069\u3057\u305f\u6587\u66f8\u3092\u9806\u6b21\u3064\u3051\u308b\u6642\u306b\u7528\u3044\u3089\u308c\u307e\u3059\u3002<\/span><\/p>\n<p><span style=\"font-weight: 400\">1970\u5e74\u4ee3\u304b\u30891980\u5e74\u4ee3\u306e\u6642\u671f\u306b\u3001\u30ab\u30ec\u30f3\u30fb\u30b9\u30d1\u30fc\u30af\u30fb\u30b8\u30e7\u30fc\u30f3\u30ba\u3084\u30b9\u30c6\u30a3\u30fc\u30d6\u30f3\u30fb\u30ed\u30d0\u30fc\u30c8\u30bd\u30f3\u3089\u304c\u958b\u767a\u3057\u305f\u3082\u306e\u3067\u3001\u82f1\u8a9e\u7248\u3067\u306f\u78ba\u7387\u9069\u5408\u30e2\u30c7\u30eb\u306b\u57fa\u3065\u3044\u3066\u3044\u307e\u3059\u3002<\/span><\/p>\n<p><span style=\"font-weight: 400\">\u306a\u304a\u3001BM25\u306eBM\u306fBest Matching\u3092\u7565\u3057\u305f\u3082\u306e\u3067\u3059\u3002<\/span><\/p>\n<h2><span class=\"ez-toc-section\" id=\"%E4%B8%80%E8%88%AC%E7%9A%84%E3%81%AA%E6%B4%BB%E7%94%A8%E6%96%B9%E6%B3%95%E3%80%81%E6%A7%98%E3%80%85%E3%81%AA%E7%9B%AE%E7%B7%9A%E3%81%8B%E3%82%89%E7%B4%B9%E4%BB%8B\"><\/span><span id=\"i-5\"><span style=\"font-weight: 400\">\u4e00\u822c\u7684\u306a\u6d3b\u7528\u65b9\u6cd5\u3001\u69d8\u3005\u306a\u76ee\u7dda\u304b\u3089\u7d39\u4ecb<\/span><\/span><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p><img decoding=\"async\" class=\"alignnone size-full wp-image-2565\" src=\"https:\/\/sirprize.co.jp\/meo\/wp-content\/uploads\/2021\/06\/AdobeStock_310133662-scaled-e1623980366824.jpeg\" alt=\"TF-IDF\" width=\"750\" height=\"321\" \/><\/p>\n<p><span style=\"font-weight: 400\">Web\u30da\u30fc\u30b8\u4e0a\u3067\u5927\u5207\u306a\u3053\u3068\u306f\u3001\u30e6\u30fc\u30b6\u30fc\u304b\u3089\u53d7\u3051\u53d6\u3063\u305f\u30af\u30a8\u30ea(\u554f\u3044\u304b\u3051)\u306b\u3069\u306e\u30da\u30fc\u30b8\u304c\u95a2\u9023\u3057\u3066\u304a\u308a\u3001\u95a2\u9023\u3057\u3066\u3044\u306a\u3044\u30da\u30fc\u30b8\u304c\u3069\u308c\u306a\u306e\u304b\u3092\u5224\u5b9a\u3059\u308b\u3053\u3068\u3067\u3059\u3002<\/span><\/p>\n<p><span style=\"font-weight: 400\">\u305d\u3053\u3067\u3001\u30b3\u30f3\u30c6\u30f3\u30c4\u4f5c\u6210\u8005\u306e\u6d3b\u7528\u65b9\u6cd5\u3068\u3057\u3066\u3001\u6700\u3082\u53e4\u3044\u30c9\u30ad\u30e5\u30e1\u30f3\u30c8\u51e6\u7406\u65b9\u6cd5\u306bTF-IDF\u3092\u4f7f\u3044\u3001\u5404\u3005\u306e\u30da\u30fc\u30b8\u304c\u3069\u306e\u7a0b\u5ea6\u30ad\u30fc\u30ef\u30fc\u30c9\u3068\u4e00\u81f4\u3057\u3066\u3044\u308b\u304b\u3092\u8a08\u7b97\u3057\u307e\u3059\u3002\u3064\u307e\u308a\u3001\u300c\u30da\u30fc\u30b8\u30aa\u30fc\u30bd\u30ea\u30c6\u30a3\u300d\u3068\u300c\u8a00\u8a9e\u30e2\u30c7\u30eb\u300d\u3092\u4f7f\u3063\u3066\u3001\u9069\u5408\u7387\u306e\u9ad8\u3044\u30da\u30fc\u30b8\u3092\u4f5c\u308b\u3053\u3068\u3067\u3059\u3002<\/span><\/p>\n<p><span class=\"ymarker\"><strong>TF-IDF\u3092\u4f7f\u3048\u3070\u3001\u30ad\u30fc\u30ef\u30fc\u30c9\u306e\u691c\u7d22\u7d50\u679c\u306b\u5bfe\u3057\u3066\u4e0a\u4f4d\u8868\u793a\u3055\u308c\u3066\u3044\u308b\u30b5\u30a4\u30c8\u304c\u3001\u30da\u30fc\u30b8\u5185\u306b\u3069\u306e\u3088\u3046\u306a\u5358\u8a9e\u3092\u4f7f\u3063\u3066\u3044\u308b\u306e\u304b\u3092\u77e5\u308b\u3053\u3068\u304c\u3067\u304d\u307e\u3059\u3002<\/strong><\/span><\/p>\n<h2><span class=\"ez-toc-section\" id=\"MEO%E3%81%AB%E3%81%8A%E3%81%91%E3%82%8B%E5%84%AA%E4%BD%8D%E7%82%B9%E3%83%BB%E3%83%A1%E3%83%AA%E3%83%83%E3%83%88%E3%83%BB%E6%B3%A8%E6%84%8F%E7%82%B9\"><\/span><span id=\"MEO\"><span style=\"font-weight: 400\">MEO\u306b\u304a\u3051\u308b\u512a\u4f4d\u70b9\u30fb\u30e1\u30ea\u30c3\u30c8\u30fb\u6ce8\u610f\u70b9<\/span><\/span><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p><span style=\"font-weight: 400\">MEO\u3068\u306f\u3001Google\u30de\u30c3\u30d7\u306b\u304a\u3051\u308b\u300c\u30de\u30c3\u30d7\u30a8\u30f3\u30b8\u30f3\u6700\u9069\u5316\u300d\u3092\u6307\u3059\u8a00\u8449\u3067\u3059\u3002<\/span><\/p>\n<p><span style=\"font-weight: 400\">\u591a\u304f\u306e\u5834\u5408\u300c\u5730\u57df\u3000\u25cb\u25cb\u5c4b\u300d\u306e\u3088\u3046\u306b\u691c\u7d22\u3055\u308c\u308b\u3053\u3068\u304b\u3089\u3001TF-IDF\u3092\u7528\u3044\u3066\u91cd\u8981\u306a\u5358\u8a9e\u3092\u5224\u5b9a\u3059\u308b\u3053\u3068\u304c\u91cd\u8981\u3067\u3059\u3002<\/span><\/p>\n<p><span style=\"color: #ff0000\"><strong>TF-IDF\u3092\u5b9f\u88c5\u3057\u3001MEO\u3068\u7d44\u307f\u5408\u308f\u305b\u308b\u3053\u3068\u3067\u3001\u30e6\u30fc\u30b6\u30fc\u306f\u3088\u308a\u65e9\u304f\u81ea\u793e\u306e\u5e97\u8217\u3092\u898b\u3064\u3051\u3084\u3059\u304f\u306a\u308b\u3068\u3044\u3046\u30e1\u30ea\u30c3\u30c8\u304c\u751f\u307e\u308c\u307e\u3059\u3002<\/strong><\/span><\/p>\n<p><span style=\"font-weight: 400\">\u6ce8\u610f\u70b9\u3068\u3057\u3066\u306f\u3001\u30af\u30a8\u30ea\u306b\u542b\u307e\u308c\u308b\u3067\u3042\u308d\u3046\u5358\u8a9e\u3084\u30b9\u30da\u30eb\u306b\u30df\u30b9\u304c\u7121\u3044\u3088\u3046\u3001\u6c17\u3092\u4ed8\u3051\u306a\u3051\u308c\u3070\u306a\u3089\u306a\u3044\u3068\u3044\u3046\u3053\u3068\u304c\u6319\u3052\u3089\u308c\u307e\u3059\u3002<\/span><\/p>\n<h2><span class=\"ez-toc-section\" id=\"%E9%96%A2%E9%80%A3%E3%82%AD%E3%83%BC%E3%83%AF%E3%83%BC%E3%83%89\"><\/span><span id=\"i-6\">\u95a2\u9023\u30ad\u30fc\u30ef\u30fc\u30c9<\/span><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p><a href=\"https:\/\/sirprize.co.jp\/meo\/word\/natural-language-processing\">\u81ea\u7136\u8a00\u8a9e\u51e6\u7406<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"<p>TF-IDF\u3068\u306f tf-idf\u3068\u306f\u3001\u60c5\u5831\u63a2\u7d22\u3084\u30c6\u30ad\u30b9\u30c8\u30de\u30a4\u30cb\u30f3\u30b0\u306a\u3069\u306e\u5206\u91ce\u3067\u5229\u7528\u3055\u308c\u308b\u3001\u6587\u66f8\u4e2d\u306b\u51fa\u73fe\u3057\u305f\u7279\u5b9a\u306e\u5358\u8a9e\u304c\u3069\u306e\u304f\u3089\u3044\u7279\u5fb4\u7684\u3067\u3042\u308b\u304b\u3092\u8b58\u5225\u3059\u308b\u305f\u3081\u306e\u6307\u6a19\u306e\u3053\u3068\u3067\u3042\u308b\u3002 &gt;&gt;\u3000MEO &#8230; <\/p>\n","protected":false},"author":4,"featured_media":2564,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[26],"tags":[12,65,28],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/sirprize.co.jp\/meo\/wp-json\/wp\/v2\/posts\/2563"}],"collection":[{"href":"https:\/\/sirprize.co.jp\/meo\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/sirprize.co.jp\/meo\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/sirprize.co.jp\/meo\/wp-json\/wp\/v2\/users\/4"}],"replies":[{"embeddable":true,"href":"https:\/\/sirprize.co.jp\/meo\/wp-json\/wp\/v2\/comments?post=2563"}],"version-history":[{"count":4,"href":"https:\/\/sirprize.co.jp\/meo\/wp-json\/wp\/v2\/posts\/2563\/revisions"}],"predecessor-version":[{"id":3010,"href":"https:\/\/sirprize.co.jp\/meo\/wp-json\/wp\/v2\/posts\/2563\/revisions\/3010"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/sirprize.co.jp\/meo\/wp-json\/wp\/v2\/media\/2564"}],"wp:attachment":[{"href":"https:\/\/sirprize.co.jp\/meo\/wp-json\/wp\/v2\/media?parent=2563"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/sirprize.co.jp\/meo\/wp-json\/wp\/v2\/categories?post=2563"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/sirprize.co.jp\/meo\/wp-json\/wp\/v2\/tags?post=2563"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}