{"id":4156,"date":"2025-07-06T21:13:16","date_gmt":"2025-07-06T12:13:16","guid":{"rendered":"https:\/\/best-biostatistics.com\/toukei-er\/?p=4156"},"modified":"2025-07-06T21:14:50","modified_gmt":"2025-07-06T12:14:50","slug":"understanding-difference-in-differences-a-powerful-tool-for-causal-inference","status":"publish","type":"post","link":"https:\/\/best-biostatistics.com\/toukei-er\/entry\/understanding-difference-in-differences-a-powerful-tool-for-causal-inference\/","title":{"rendered":"\u5dee\u5206\u306e\u5dee\u5206\u6cd5\u3092\u7406\u89e3\u3059\u308b\uff1a\u56e0\u679c\u63a8\u8ad6\u306e\u5f37\u529b\u306a\u30c4\u30fc\u30eb"},"content":{"rendered":"\n<p>\u5dee\u5206\u306e\u5dee\u5206\u6cd5\uff08Difference-in-Differences, DiD\uff09\u306f\u3001\u653f\u7b56\u5909\u66f4\u3084\u4ecb\u5165\u306e\u52b9\u679c\u3092\u8a55\u4fa1\u3059\u308b\u969b\u306b\u975e\u5e38\u306b\u5f37\u529b\u306a\u7d71\u8a08\u7684\u624b\u6cd5\u3060\u3002\u3053\u306e\u8a18\u4e8b\u3067\u306f\u3001DiD\u306e\u57fa\u672c\u7684\u306a\u8003\u3048\u65b9\u304b\u3089\u3001\u305d\u306e<strong>\u4f7f\u3044\u6240<\/strong>\u3001<strong>\u95a2\u9023\u3059\u308b\u7d71\u8a08\u624b\u6cd5\u3068\u306e\u9055\u3044<\/strong>\u3001DiD\u306e\u6838\u5fc3\u3067\u3042\u308b<strong>\u4e26\u884c\u30c8\u30ec\u30f3\u30c9\u306e\u4eee\u5b9a<\/strong>\u306b\u3064\u3044\u3066\u8a73\u3057\u304f\u89e3\u8aac\u3057\u3001\u5177\u4f53\u7684\u306aR\u3067\u306e\u8a08\u7b97\u4f8b\u3001\u305d\u3057\u3066\u305d\u306e\u7d50\u679c\u306e\u89e3\u91c8\u307e\u3067\u3092\u5206\u304b\u308a\u3084\u3059\u304f\u89e3\u8aac\u3059\u308b\u3002<\/p>\n\n\n\n<!--more-->\n\n\n\n<h2 class=\"wp-block-heading\">\u5dee\u5206\u306e\u5dee\u5206\u6cd5\u306e\u6982\u8981<\/h2>\n\n\n\n<p>\u5dee\u5206\u306e\u5dee\u5206\u6cd5\u306f\u3001\u3042\u308b\u4ecb\u5165\u304c\u7279\u5b9a\u306e\u30b0\u30eb\u30fc\u30d7\u306b\u4e0e\u3048\u308b\u5f71\u97ff\u3092\u3001\u305d\u306e\u4ecb\u5165\u3092\u53d7\u3051\u306a\u304b\u3063\u305f\u5bfe\u7167\u30b0\u30eb\u30fc\u30d7\u3068\u6bd4\u8f03\u3059\u308b\u3053\u3068\u3067\u3001\u56e0\u679c\u52b9\u679c\u3092\u63a8\u5b9a\u3059\u308b\u624b\u6cd5\u3060\u3002\u3053\u306e\u65b9\u6cd5\u306e\u6838\u5fc3\u306f\u3001\u300c\u4ecb\u5165\u30b0\u30eb\u30fc\u30d7\u3068\u5bfe\u7167\u30b0\u30eb\u30fc\u30d7\u304c\u3001\u4ecb\u5165\u304c\u306a\u304b\u3063\u305f\u3068\u3057\u305f\u3089\u540c\u69d8\u306e\u30c8\u30ec\u30f3\u30c9\u3092\u8fbf\u3063\u3066\u3044\u305f\u3067\u3042\u308d\u3046\u300d\u3068\u3044\u3046<strong>\u4e26\u884c\u30c8\u30ec\u30f3\u30c9\u306e\u4eee\u5b9a<\/strong>\u306b\u3042\u308b\u3002<\/p>\n\n\n\n<p>DiD\u306f\u3001\u4e3b\u306b\u4ee5\u4e0b\u306e2\u3064\u306e\u5dee\u5206\u3092\u53d6\u308b\u3053\u3068\u3067\u52b9\u679c\u3092\u6e2c\u5b9a\u3059\u308b\u3002<\/p>\n\n\n\n<ol start=\"1\" class=\"wp-block-list\">\n<li><strong>\u6642\u9593\u8ef8\u3067\u306e\u5dee\u5206<\/strong>: \u4ecb\u5165\u524d\u3068\u4ecb\u5165\u5f8c\u306e\u5909\u5316<\/li>\n\n\n\n<li><strong>\u30b0\u30eb\u30fc\u30d7\u9593\u3067\u306e\u5dee\u5206<\/strong>: \u4ecb\u5165\u30b0\u30eb\u30fc\u30d7\u3068\u5bfe\u7167\u30b0\u30eb\u30fc\u30d7\u9593\u306e\u5909\u5316<\/li>\n<\/ol>\n\n\n\n<p>\u3053\u308c\u30892\u3064\u306e\u5dee\u5206\u3092\u7d44\u307f\u5408\u308f\u305b\u308b\u3053\u3068\u3067\u3001\u4ecb\u5165\u306b\u3088\u308b\u7d14\u7c8b\u306a\u52b9\u679c\u3092\u62bd\u51fa\u3059\u308b\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">\u5dee\u5206\u306e\u5dee\u5206\u6cd5\u306e\u4f7f\u3044\u6240<\/h2>\n\n\n\n<p>\u5dee\u5206\u306e\u5dee\u5206\u6cd5\u306f\u3001\u4ee5\u4e0b\u306e\u3088\u3046\u306a\u72b6\u6cc1\u3067\u7279\u306b\u6709\u52b9\u3060\u3002<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>\u81ea\u7136\u5b9f\u9a13<\/strong>: \u653f\u7b56\u5909\u66f4\u3084\u5236\u5ea6\u5c0e\u5165\u306a\u3069\u3001\u7814\u7a76\u8005\u304c\u30b3\u30f3\u30c8\u30ed\u30fc\u30eb\u3067\u304d\u306a\u3044\u304c\u3001\u4e00\u90e8\u306e\u30b0\u30eb\u30fc\u30d7\u306b\u306e\u307f\u5f71\u97ff\u3092\u4e0e\u3048\u308b\u3088\u3046\u306a\u300c\u81ea\u7136\u300d\u306b\u767a\u751f\u3057\u305f\u4ecb\u5165\u306e\u52b9\u679c\u3092\u8a55\u4fa1\u3059\u308b\u5834\u5408\u3002<\/li>\n\n\n\n<li><strong>\u6e96\u5b9f\u9a13<\/strong>: \u30e9\u30f3\u30c0\u30e0\u5316\u6bd4\u8f03\u8a66\u9a13\uff08RCT\uff09\u304c\u56f0\u96e3\u306a\u72b6\u6cc1\u3067\u3001\u4ecb\u5165\u3092\u53d7\u3051\u308b\u30b0\u30eb\u30fc\u30d7\u3068\u53d7\u3051\u306a\u3044\u30b0\u30eb\u30fc\u30d7\u304c\u5b58\u5728\u3057\u3001\u304b\u3064\u4ecb\u5165\u524d\u5f8c\u306e\u30c7\u30fc\u30bf\u304c\u5229\u7528\u53ef\u80fd\u306a\u5834\u5408\u3002<\/li>\n\n\n\n<li><strong>\u4ecb\u5165\u52b9\u679c\u306e\u56e0\u679c\u7684\u63a8\u5b9a<\/strong>: \u4ecb\u5165\u306e\u6709\u7121\u3060\u3051\u3067\u306a\u304f\u3001\u4ecb\u5165\u5f8c\u306e\u6642\u9593\u7d4c\u904e\u306b\u3088\u308b\u5909\u5316\u3092\u8003\u616e\u3057\u3001\u4ed6\u306e\u8981\u56e0\u306b\u3088\u308b\u5f71\u97ff\u3092\u6392\u9664\u3057\u3066\u7d14\u7c8b\u306a\u4ecb\u5165\u52b9\u679c\u3092\u77e5\u308a\u305f\u3044\u5834\u5408\u3002<\/li>\n<\/ul>\n\n\n\n<p>\u305f\u3068\u3048\u3070\u3001\u65b0\u3057\u3044\u6cd5\u5f8b\u306e\u5c0e\u5165\u304c\u72af\u7f6a\u7387\u306b\u4e0e\u3048\u308b\u5f71\u97ff\u3001\u7279\u5b9a\u306e\u6559\u80b2\u30d7\u30ed\u30b0\u30e9\u30e0\u304c\u5b66\u696d\u6210\u7e3e\u306b\u4e0e\u3048\u308b\u5f71\u97ff\u3001\u516c\u5171\u4ea4\u901a\u6a5f\u95a2\u306e\u904b\u8cc3\u6539\u5b9a\u304c\u5229\u7528\u8005\u306b\u4e0e\u3048\u308b\u5f71\u97ff\u306a\u3069\u3092\u5206\u6790\u3059\u308b\u969b\u306b\u5229\u7528\u3067\u304d\u308b\u3002<\/p>\n\n\n\n<div id=\"biost-1819758057\" class=\"biost- biost-entity-placement\"><p style=\"text-align: center;\"><span style=\"font-size: 20px;\"><strong><a href=\"https:\/\/best-biostatistics.com\/kmhl\">\uff1e\uff1e\u3082\u3046\u7d71\u8a08\u3067\u60a9\u3080\u306e\u306f\u7d42\u308f\u308a\u306b\u3057\u307e\u305b\u3093\u304b\uff1f\u00a0<\/a><\/strong><\/span><\/p>\r\n<a href=\"https:\/\/best-biostatistics.com\/kmhl\"><img class=\"aligncenter wp-image-2794 size-full\" src=\"https:\/\/best-biostatistics.com\/wp\/wp-content\/uploads\/2023\/11\/bn_r_03.png\" alt=\"\" width=\"500\" height=\"327\" \/><\/a>\r\n<p style=\"text-align: center;\"><span style=\"color: #ff0000; font-size: 20px;\"><strong><span class=\"marker2\">\u21911\u4e07\u4eba\u4ee5\u4e0a\u306e\u533b\u7642\u5f93\u4e8b\u8005\u304c\u8cfc\u8aad\u4e2d<\/span><\/strong><\/span><\/p><\/div><h2 class=\"wp-block-heading\">\u4ea4\u4e92\u4f5c\u7528\u9805\u3042\u308a\u306e\u91cd\u56de\u5e30\u5206\u6790\u307e\u305f\u306f\u4e8c\u5143\u914d\u7f6e\u5206\u6563\u5206\u6790\u3068\u306e\u9055\u3044<\/h2>\n\n\n\n<p>DiD\u306f\u3001\u305d\u306e\u69cb\u9020\u4e0a\u3001\u4ea4\u4e92\u4f5c\u7528\u9805\u3092\u542b\u3080\u91cd\u56de\u5e30\u5206\u6790\u3084\u4e8c\u5143\u914d\u7f6e\u5206\u6563\u5206\u6790\u3068\u975e\u5e38\u306b\u3088\u304f\u4f3c\u3066\u3044\u308b\u3002\u3057\u304b\u3057\u3001\u305d\u306e\u76ee\u7684\u3068\u4eee\u5b9a\u306b\u91cd\u8981\u306a\u9055\u3044\u304c\u3042\u308b\u3002<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>\u91cd\u56de\u5e30\u5206\u6790\uff08\u4ea4\u4e92\u4f5c\u7528\u9805\u3042\u308a\uff09<\/strong>: \u4e00\u822c\u7684\u306a\u91cd\u56de\u5e30\u5206\u6790\u306b\u4ea4\u4e92\u4f5c\u7528\u9805\u3092\u542b\u3081\u308b\u3053\u3068\u3067\u3001\u3042\u308b\u5909\u6570\u304c\u4ed6\u306e\u5909\u6570\u306e\u52b9\u679c\u3092\u3069\u306e\u3088\u3046\u306b\u5909\u3048\u308b\u304b\u3092\u8a55\u4fa1\u3067\u304d\u308b\u3002DiD\u306f\u3001\u3053\u306e\u91cd\u56de\u5e30\u30e2\u30c7\u30eb\u306e\u7279\u6b8a\u306a\u30b1\u30fc\u30b9\u3068\u898b\u306a\u3059\u3053\u3068\u304c\u3067\u304d\u308b\u3002DiD\u306b\u304a\u3051\u308b\u4ea4\u4e92\u4f5c\u7528\u9805\u306f\u3001\u300c\u4ecb\u5165\u30b0\u30eb\u30fc\u30d7\u3067\u3042\u308b\u3053\u3068\u300d\u3068\u300c\u4ecb\u5165\u5f8c\u306e\u671f\u9593\u3067\u3042\u308b\u3053\u3068\u300d\u306e\u7d44\u307f\u5408\u308f\u305b\u304c\u30a2\u30a6\u30c8\u30ab\u30e0\u306b\u4e0e\u3048\u308b\u8ffd\u52a0\u7684\u306a\u5f71\u97ff\u3092\u8868\u3059\u3002<\/li>\n\n\n\n<li><strong>\u4e8c\u5143\u914d\u7f6e\u5206\u6563\u5206\u6790\uff08Two-way ANOVA\uff09<\/strong>: \u4e8c\u5143\u914d\u7f6e\u5206\u6563\u5206\u6790\u306f\u30012\u3064\u306e\u8981\u56e0\uff08\u4f8b\u3048\u3070\u3001\u30b0\u30eb\u30fc\u30d7\u3068\u6642\u9593\uff09\u304c\u5f93\u5c5e\u5909\u6570\u306b\u4e0e\u3048\u308b\u5f71\u97ff\u3092\u8a55\u4fa1\u3057\u3001\u305d\u308c\u3089\u306e\u9593\u306b\u4ea4\u4e92\u4f5c\u7528\u304c\u3042\u308b\u304b\u3069\u3046\u304b\u3082\u8abf\u3079\u308b\u3053\u3068\u304c\u3067\u304d\u308b\u3002DiD\u306f\u3001\u4e8c\u5143\u914d\u7f6e\u5206\u6563\u5206\u6790\u306e\u67a0\u7d44\u307f\u306e\u4e2d\u3067\u3001\u300c\u30b0\u30eb\u30fc\u30d7\u300d\u3068\u300c\u6642\u9593\u300d\u306e\u4ea4\u4e92\u4f5c\u7528\u52b9\u679c\u3068\u3057\u3066\u4ecb\u5165\u52b9\u679c\u3092\u6349\u3048\u308b\u3053\u3068\u304c\u3067\u304d\u308b\u3002<\/li>\n<\/ul>\n\n\n\n<p>DiD\u3068\u306e\u672c\u8cea\u7684\u306a\u9055\u3044:<\/p>\n\n\n\n<p>DiD\u304c\u3053\u308c\u3089\u306e\u7d71\u8a08\u624b\u6cd5\u3068\u7570\u306a\u308b\u306e\u306f\u3001\u5358\u306b\u4ea4\u4e92\u4f5c\u7528\u52b9\u679c\u3092\u691c\u51fa\u3059\u308b\u3060\u3051\u3067\u306a\u304f\u3001\u305d\u306e\u4ea4\u4e92\u4f5c\u7528\u52b9\u679c\u304c<strong>\u56e0\u679c\u95a2\u4fc2\u3092\u793a\u3059\u3068\u89e3\u91c8\u3059\u308b\u305f\u3081\u306e\u5f37\u3044\u4eee\u5b9a\uff08\u4e26\u884c\u30c8\u30ec\u30f3\u30c9\u306e\u4eee\u5b9a\uff09<\/strong>\u3092\u5fc5\u8981\u3068\u3059\u308b\u3053\u3068\u3060\u3002\u5358\u306a\u308b\u4ea4\u4e92\u4f5c\u7528\u9805\u306e\u4fc2\u6570\u3092\u898b\u308b\u3060\u3051\u3067\u306f\u3001\u300c\u3082\u3057\u4ecb\u5165\u304c\u306a\u3051\u308c\u3070\u3001\u4e21\u30b0\u30eb\u30fc\u30d7\u306f\u540c\u3058\u30c8\u30ec\u30f3\u30c9\u3092\u8fbf\u3063\u3066\u3044\u305f\u3067\u3042\u308d\u3046\u300d\u3068\u3044\u3046\u56e0\u679c\u7684\u306a\u89e3\u91c8\u306f\u3067\u304d\u306a\u3044\u3002DiD\u306f\u3001\u3053\u306e\u4e26\u884c\u30c8\u30ec\u30f3\u30c9\u306e\u4eee\u5b9a\u304c\u6e80\u305f\u3055\u308c\u308b\u5834\u5408\u306b\u306e\u307f\u3001\u56e0\u679c\u52b9\u679c\u306e\u63a8\u5b9a\u5024\u3068\u3057\u3066\u4fe1\u983c\u3067\u304d\u308b\u3082\u306e\u3068\u306a\u308b\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">\u4e26\u884c\u30c8\u30ec\u30f3\u30c9\u306e\u4eee\u5b9a\u306b\u3064\u3044\u3066<\/h2>\n\n\n\n<p><strong>\u4e26\u884c\u30c8\u30ec\u30f3\u30c9\u306e\u4eee\u5b9a (Parallel Trends Assumption)<\/strong> \u306f\u3001\u5dee\u5206\u306e\u5dee\u5206\u6cd5\u306b\u304a\u3044\u3066\u6700\u3082\u91cd\u8981\u306a\u4eee\u5b9a\u3060\u3002\u3053\u306e\u4eee\u5b9a\u306f\u3001<strong>\u3082\u3057\u4ecb\u5165\u304c\u5b9f\u65bd\u3055\u308c\u306a\u304b\u3063\u305f\u3068\u3057\u305f\u3089\u3001\u4ecb\u5165\u30b0\u30eb\u30fc\u30d7\u3068\u5bfe\u7167\u30b0\u30eb\u30fc\u30d7\u306e\u30a2\u30a6\u30c8\u30ab\u30e0\uff08\u7d50\u679c\u5909\u6570\uff09\u306f\u6642\u9593\u3068\u3068\u3082\u306b\u540c\u69d8\u306e\u50be\u5411\u3092\u305f\u3069\u3063\u3066\u3044\u305f\u3060\u308d\u3046<\/strong>\u3001\u3068\u3044\u3046\u3053\u3068\u3092\u610f\u5473\u3059\u308b\u3002<\/p>\n\n\n\n<p>\u3053\u306e\u4eee\u5b9a\u304c\u6e80\u305f\u3055\u308c\u3066\u3044\u308c\u3070\u3001\u4ecb\u5165\u30b0\u30eb\u30fc\u30d7\u3068\u5bfe\u7167\u30b0\u30eb\u30fc\u30d7\u306e\u30a2\u30a6\u30c8\u30ab\u30e0\u306e\u30c8\u30ec\u30f3\u30c9\u306e\u9055\u3044\u306f\u3001\u4ecb\u5165\u306b\u3088\u308b\u3082\u306e\u3060\u3068\u7d50\u8ad6\u3065\u3051\u308b\u3053\u3068\u304c\u3067\u304d\u308b\u3002\u3057\u304b\u3057\u3001\u3053\u306e\u4eee\u5b9a\u304c\u7834\u3089\u308c\u3066\u3044\u308b\u5834\u5408\u3001DiD\u306b\u3088\u3063\u3066\u63a8\u5b9a\u3055\u308c\u305f\u52b9\u679c\u306f\u3001\u4ecb\u5165\u4ee5\u5916\u306e\u8981\u56e0\u306b\u3088\u308b\u3082\u306e\u3067\u3042\u308b\u53ef\u80fd\u6027\u304c\u3042\u308a\u3001\u56e0\u679c\u52b9\u679c\u3092\u6b63\u3057\u304f\u6e2c\u5b9a\u3067\u304d\u306a\u3044\u3002<\/p>\n\n\n\n<p><strong>\u4e26\u884c\u30c8\u30ec\u30f3\u30c9\u306e\u4eee\u5b9a\u306e\u691c\u8a3c\u65b9\u6cd5<\/strong>:<\/p>\n\n\n\n<ul start=\"1\" class=\"wp-block-list\">\n<li><strong>\u4ecb\u5165\u524d\u306e\u30c8\u30ec\u30f3\u30c9\u306e\u8996\u899a\u7684\u78ba\u8a8d<\/strong>: \u4ecb\u5165\u524d\u306e\u671f\u9593\u306b\u304a\u3044\u3066\u3001\u4ecb\u5165\u30b0\u30eb\u30fc\u30d7\u3068\u5bfe\u7167\u30b0\u30eb\u30fc\u30d7\u306e\u30a2\u30a6\u30c8\u30ab\u30e0\u306e\u5e73\u5747\u5024\u306e\u6642\u7cfb\u5217\u30d7\u30ed\u30c3\u30c8\u3092\u4f5c\u6210\u3057\u3001\u4e21\u30b0\u30eb\u30fc\u30d7\u306e\u30c8\u30ec\u30f3\u30c9\u304c\u8996\u899a\u7684\u306b\u4e26\u884c\u3067\u3042\u308b\u304b\u3092\u78ba\u8a8d\u3059\u308b\u3002\u3053\u308c\u306f\u3001\u4eee\u5b9a\u306e\u59a5\u5f53\u6027\u3092\u8a55\u4fa1\u3059\u308b\u305f\u3081\u306e\u6700\u3082\u4e00\u822c\u7684\u306a\u65b9\u6cd5\u3060\u3002<\/li>\n\n\n\n<li><strong>\u4ecb\u5165\u524d\u306e\u6642\u70b9\u3067\u306e\u30c0\u30df\u30fc\u5909\u6570\u3068\u4ecb\u5165\u30b0\u30eb\u30fc\u30d7\u30c0\u30df\u30fc\u306e\u4ea4\u4e92\u4f5c\u7528\u9805\u306e\u6709\u610f\u6027\u306e\u78ba\u8a8d<\/strong>: \u7d71\u8a08\u7684\u306b\u3001\u4ecb\u5165\u524d\u306e\u5404\u6642\u70b9\u3092\u8868\u3059\u30c0\u30df\u30fc\u5909\u6570\u3068\u4ecb\u5165\u30b0\u30eb\u30fc\u30d7\u30c0\u30df\u30fc\u3068\u306e\u4ea4\u4e92\u4f5c\u7528\u9805\u3092\u56de\u5e30\u30e2\u30c7\u30eb\u306b\u542b\u3081\u3001\u305d\u308c\u3089\u306e\u4fc2\u6570\u304c\u7d71\u8a08\u7684\u306b\u6709\u610f\u3067\u306a\u3044\u3053\u3068\u3092\u78ba\u8a8d\u3059\u308b\u3002\u6709\u610f\u306a\u4fc2\u6570\u304c\u3042\u308b\u5834\u5408\u3001\u4ecb\u5165\u524d\u306b\u65e2\u306b\u30c8\u30ec\u30f3\u30c9\u306b\u5dee\u304c\u3042\u3063\u305f\u3053\u3068\u3092\u793a\u5506\u3059\u308b\u3002<\/li>\n\n\n\n<li><strong>\u4ed6\u306e\u4ea4\u7d61\u56e0\u5b50\u306e\u8003\u616e<\/strong>: \u4ecb\u5165\u30b0\u30eb\u30fc\u30d7\u3068\u5bfe\u7167\u30b0\u30eb\u30fc\u30d7\u3067\u3001\u4ecb\u5165\u4ee5\u5916\u306e\u8981\u56e0\u304c\u6642\u9593\u3068\u3068\u3082\u306b\u7570\u306a\u308b\u5f71\u97ff\u3092\u4e0e\u3048\u3066\u3044\u306a\u3044\u304b\u3092\u691c\u8a0e\u3057\u3001\u5fc5\u8981\u3067\u3042\u308c\u3070\u305d\u308c\u3089\u3092\u30e2\u30c7\u30eb\u306b\u542b\u3081\u3066\u8abf\u6574\u3059\u308b\u3002<\/li>\n<\/ul>\n\n\n\n<p>\u4e26\u884c\u30c8\u30ec\u30f3\u30c9\u306e\u4eee\u5b9a\u306f\u76f4\u63a5\u7684\u306b\u30c6\u30b9\u30c8\u3067\u304d\u308b\u3082\u306e\u3067\u306f\u306a\u304f\u3001\u904e\u53bb\u306e\u30c7\u30fc\u30bf\u3084\u95a2\u9023\u3059\u308b\u7406\u8ad6\u7684\u6839\u62e0\u306b\u57fa\u3065\u3044\u3066\u305d\u306e\u59a5\u5f53\u6027\u3092\u5224\u65ad\u3059\u308b\u5fc5\u8981\u304c\u3042\u308b\u3002<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">\u5dee\u5206\u306e\u5dee\u5206\u6cd5\u306e\u5177\u4f53\u4f8b<\/h2>\n\n\n\n<p>\u5b66\u6821\u7d66\u98df\u306e\u7121\u511f\u5316\u304c\u3001\u5150\u7ae5\u306e\u5b66\u7fd2\u6210\u7e3e\u306b\u4e0e\u3048\u308b\u5f71\u97ff\u3092\u8a55\u4fa1\u3057\u305f\u3044\u3068\u3059\u308b\u3002<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>\u4ecb\u5165\u30b0\u30eb\u30fc\u30d7<\/strong>: \u5b66\u6821\u7d66\u98df\u304c\u7121\u511f\u5316\u3055\u308c\u305f\u5730\u57df\u306e\u5b66\u6821<\/li>\n\n\n\n<li><strong>\u5bfe\u7167\u30b0\u30eb\u30fc\u30d7<\/strong>: \u5b66\u6821\u7d66\u98df\u304c\u7121\u511f\u5316\u3055\u308c\u3066\u3044\u306a\u3044\u3001\u540c\u69d8\u306e\u7279\u6027\u3092\u6301\u3064\u5730\u57df\u306e\u5b66\u6821<\/li>\n\n\n\n<li><strong>\u4ecb\u5165\u524d<\/strong>: \u7d66\u98df\u7121\u511f\u5316\u304c\u5b9f\u65bd\u3055\u308c\u308b\u524d\u306e\u5b66\u7fd2\u6210\u7e3e<\/li>\n\n\n\n<li><strong>\u4ecb\u5165\u5f8c<\/strong>: \u7d66\u98df\u7121\u511f\u5316\u304c\u5b9f\u65bd\u3055\u308c\u305f\u5f8c\u306e\u5b66\u7fd2\u6210\u7e3e<\/li>\n<\/ul>\n\n\n\n<p>\u3053\u306e\u5834\u5408\u3001\u7d66\u98df\u7121\u511f\u5316\u306b\u3088\u3063\u3066\u5b66\u7fd2\u6210\u7e3e\u304c\u3069\u306e\u3088\u3046\u306b\u5909\u5316\u3057\u305f\u304b\u3092DiD\u3067\u5206\u6790\u3059\u308b\u3002\u3053\u3053\u3067\u91cd\u8981\u306a\u306e\u306f\u3001\u4ecb\u5165\u30b0\u30eb\u30fc\u30d7\u3068\u5bfe\u7167\u30b0\u30eb\u30fc\u30d7\u304c\u3001\u7d66\u98df\u7121\u511f\u5316\u304c\u306a\u304b\u3063\u305f\u3068\u3057\u3066\u3082\u3001\u6642\u9593\u3068\u3068\u3082\u306b\u540c\u69d8\u306e\u30da\u30fc\u30b9\u3067\u5b66\u7fd2\u6210\u7e3e\u304c\u5909\u5316\u3057\u3066\u3044\u305f\u3067\u3042\u308d\u3046\u3001\u3068\u3044\u3046<strong>\u4e26\u884c\u30c8\u30ec\u30f3\u30c9\u306e\u4eee\u5b9a<\/strong>\u304c\u6210\u308a\u7acb\u3064\u3053\u3068\u3060\u3002<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">R \u8a08\u7b97\u4f8b<\/h3>\n\n\n\n<p>\u3053\u3053\u3067\u306f\u3001\u4e0a\u8a18\u306e\u5b66\u6821\u7d66\u98df\u7121\u511f\u5316\u306e\u4f8b\u3092\u3001R\u3092\u4f7f\u3063\u3066DiD\u3092\u8a08\u7b97\u3059\u308b\u65b9\u6cd5\u3092\u89e3\u8aac\u3059\u308b\u3002<\/p>\n\n\n\n<p><strong>R \u30b9\u30af\u30ea\u30d7\u30c8\u4f8b\uff1a<\/strong><\/p>\n\n\n\n<pre class=\"wp-block-code\"><code># \u5dee\u5206\u306e\u5dee\u5206\u6cd5\uff08Difference-in-Differences, DiD\uff09\u306e\u4f8b\n# \u4f8b\uff1a\u7d66\u98df\u7121\u511f\u5316\u306e\u52b9\u679c\u3092\u8a55\u4fa1\u3059\u308b\uff08\u5b66\u6821\u5358\u4f4d\u306e\u30c7\u30fc\u30bf\uff09\n\n# \u30b5\u30f3\u30d7\u30eb\u30c7\u30fc\u30bf\u306e\u751f\u6210\uff08\u5b66\u6821\u5358\u4f4d\u306e\u30c7\u30fc\u30bf\uff09\nset.seed(123)\nn_treatment_schools &lt;- 30 # \u7d66\u98df\u7121\u511f\u5316\u3092\u5b9f\u65bd\u3057\u305f\u5b66\u6821\u6570\nn_control_schools &lt;- 30 # \u7d66\u98df\u7121\u511f\u5316\u3092\u5b9f\u65bd\u3057\u306a\u304b\u3063\u305f\u5b66\u6821\u6570\n\n# \u5404\u5b66\u6821\u306e\u751f\u5f92\u6570\u3092\u30e9\u30f3\u30c0\u30e0\u306b\u751f\u6210\ntreatment_students &lt;- round(runif(n_treatment_schools, 200, 800))\ncontrol_students &lt;- round(runif(n_control_schools, 200, 800))\n\n# \u4ecb\u5165\u30b0\u30eb\u30fc\u30d7\uff08\u7d66\u98df\u7121\u511f\u5316\u5b9f\u65bd\u6821\uff09\u306e\u30c7\u30fc\u30bf\n# \u5404\u5b66\u6821\u306e\u4ecb\u5165\u524d\u5f8c\u306e\u5e73\u5747\u5b66\u7fd2\u6210\u7e3e\uff08100\u70b9\u6e80\u70b9\uff09\ntreatment_before &lt;- round(rnorm(n_treatment_schools, mean = 65, sd = 8), 1)\ntreatment_after &lt;- round(treatment_before + rnorm(n_treatment_schools, mean = 8, sd = 4), 1) # \u7d66\u98df\u52b9\u679c\n\n# \u5bfe\u7167\u30b0\u30eb\u30fc\u30d7\uff08\u7d66\u98df\u7121\u511f\u5316\u672a\u5b9f\u65bd\u6821\uff09\u306e\u30c7\u30fc\u30bf\ncontrol_before &lt;- round(rnorm(n_control_schools, mean = 63, sd = 8), 1)\ncontrol_after &lt;- round(control_before + rnorm(n_control_schools, mean = 3, sd = 4), 1) # \u81ea\u7136\u306a\u5b66\u7fd2\u52b9\u679c\n\n# \u5b66\u6821\u30ec\u30d9\u30eb\u306e\u30c7\u30fc\u30bf\u30d5\u30ec\u30fc\u30e0\u306e\u4f5c\u6210\nschool_data &lt;- data.frame(\n    school_id = 1:(n_treatment_schools + n_control_schools),\n    group = rep(\n        c(\"\u7d66\u98df\u7121\u511f\u5316\u5b9f\u65bd\u6821\", \"\u7d66\u98df\u7121\u511f\u5316\u672a\u5b9f\u65bd\u6821\"),\n        c(n_treatment_schools, n_control_schools)\n    ),\n    students = c(treatment_students, control_students),\n    score_before = c(treatment_before, control_before),\n    score_after = c(treatment_after, control_after)\n)\n\n# \u9577\u3044\u5f62\u5f0f\uff08long format\uff09\u306b\u5909\u63db\nschool_data_long &lt;- data.frame(\n    school_id = rep(school_data$school_id, 2),\n    group = rep(school_data$group, 2),\n    students = rep(school_data$students, 2),\n    time = rep(c(\"\u7d66\u98df\u7121\u511f\u5316\u524d\", \"\u7d66\u98df\u7121\u511f\u5316\u5f8c\"), each = nrow(school_data)),\n    score = c(school_data$score_before, school_data$score_after)\n)\n# time\u306b\u9806\u5e8f\u4ed8\u3051\u3055\u308c\u305f\u30ec\u30d9\u30eb\u3092\u8a2d\u5b9a\nschool_data_long$time &lt;- factor(school_data_long$time,\n    levels = c(\"\u7d66\u98df\u7121\u511f\u5316\u524d\", \"\u7d66\u98df\u7121\u511f\u5316\u5f8c\"),\n    labels = c(\"\u7d66\u98df\u7121\u511f\u5316\u524d\", \"\u7d66\u98df\u7121\u511f\u5316\u5f8c\"),\n    ordered = TRUE\n)\n\n# \u30c0\u30df\u30fc\u5909\u6570\u306e\u4f5c\u6210\nschool_data_long$group_dummy &lt;- ifelse(school_data_long$group == \"\u7d66\u98df\u7121\u511f\u5316\u5b9f\u65bd\u6821\", 1, 0)\nschool_data_long$time_dummy &lt;- ifelse(school_data_long$time == \"\u7d66\u98df\u7121\u511f\u5316\u5f8c\", 1, 0)\n\n# \u30c7\u30fc\u30bf\u306e\u78ba\u8a8d\nprint(\"=== \u5b66\u6821\u5358\u4f4d\u30c7\u30fc\u30bf\u306e\u6982\u8981 ===\")\nprint(head(school_data_long, 10))\nprint(\"\\n\u5b66\u6821\u5225\u30fb\u6642\u70b9\u5225\u306e\u5e73\u5747\u5b66\u7fd2\u6210\u7e3e:\")\nschool_means &lt;- aggregate(score ~ group + time, data = school_data_long, FUN = mean)\nprint(school_means)\n\n# \u5dee\u5206\u306e\u5dee\u5206\u6cd5\u306b\u3088\u308b\u56de\u5e30\u5206\u6790\nmodel &lt;- lm(score ~ group_dummy * time_dummy, data = school_data_long)\n\n# \u7d50\u679c\u306e\u8868\u793a\nprint(\"\\n=== \u5dee\u5206\u306e\u5dee\u5206\u6cd5\u306b\u3088\u308b\u56de\u5e30\u5206\u6790\u7d50\u679c ===\")\nprint(summary(model))\n\n\n\n# \u5dee\u5206\u306e\u5dee\u5206\u306e\u624b\u52d5\u8a08\u7b97\nprint(\"\\n=== \u5dee\u5206\u306e\u5dee\u5206\u306e\u624b\u52d5\u8a08\u7b97 ===\")\nprint(school_means)\n\n# \u4ecb\u5165\u30b0\u30eb\u30fc\u30d7\u306e\u5909\u5316\ntreatment_change &lt;- school_means$score&#91;school_means$group == \"\u7d66\u98df\u7121\u511f\u5316\u5b9f\u65bd\u6821\" &amp; school_means$time == \"\u7d66\u98df\u7121\u511f\u5316\u5f8c\"] -\n    school_means$score&#91;school_means$group == \"\u7d66\u98df\u7121\u511f\u5316\u5b9f\u65bd\u6821\" &amp; school_means$time == \"\u7d66\u98df\u7121\u511f\u5316\u524d\"]\n\n# \u5bfe\u7167\u30b0\u30eb\u30fc\u30d7\u306e\u5909\u5316\ncontrol_change &lt;- school_means$score&#91;school_means$group == \"\u7d66\u98df\u7121\u511f\u5316\u672a\u5b9f\u65bd\u6821\" &amp; school_means$time == \"\u7d66\u98df\u7121\u511f\u5316\u5f8c\"] -\n    school_means$score&#91;school_means$group == \"\u7d66\u98df\u7121\u511f\u5316\u672a\u5b9f\u65bd\u6821\" &amp; school_means$time == \"\u7d66\u98df\u7121\u511f\u5316\u524d\"]\n\n# \u5dee\u5206\u306e\u5dee\u5206\ndid_manual &lt;- treatment_change - control_change\n\ncat(sprintf(\"\\n\u7d66\u98df\u7121\u511f\u5316\u5b9f\u65bd\u6821\u306e\u5909\u5316: %.2f \u70b9\\n\", treatment_change))\ncat(sprintf(\"\u7d66\u98df\u7121\u511f\u5316\u672a\u5b9f\u65bd\u6821\u306e\u5909\u5316: %.2f \u70b9\\n\", control_change))\ncat(sprintf(\"\u5dee\u5206\u306e\u5dee\u5206\uff08\u624b\u52d5\u8a08\u7b97\uff09: %.2f \u70b9\\n\", did_manual))\ncat(sprintf(\"\u5dee\u5206\u306e\u5dee\u5206\uff08\u56de\u5e30\u4fc2\u6570\uff09: %.2f \u70b9\\n\", coef(model)&#91;\"group_dummy:time_dummy\"]))\n\n# \u53ef\u8996\u5316\nlibrary(ggplot2)\n\n# \u5e73\u5747\u5024\u306e\u30d7\u30ed\u30c3\u30c8\np1 &lt;- ggplot(school_means, aes(x = time, y = score, group = group, color = group)) +\n    geom_line(linewidth = 1.5) +\n    geom_point(size = 3) +\n    labs(\n        title = \"\u5dee\u5206\u306e\u5dee\u5206\u6cd5\u306b\u3088\u308b\u7d66\u98df\u7121\u511f\u5316\u52b9\u679c\u306e\u53ef\u8996\u5316\",\n        subtitle = \"\u5b66\u6821\u5358\u4f4d\u306e\u5e73\u5747\u5b66\u7fd2\u6210\u7e3e\",\n        x = \"\u6642\u70b9\", y = \"\u5e73\u5747\u5b66\u7fd2\u6210\u7e3e (\u70b9)\", color = \"\u30b0\u30eb\u30fc\u30d7\"\n    ) +\n    theme_minimal() +\n    theme(legend.position = \"bottom\")\nprint(p1)\nggsave(\"Difference-in-difference_method.png\", width = 10, height = 8)\n<\/code><\/pre>\n\n\n\n<p><strong>\u5b9f\u884c\u7d50\u679c\uff1a<\/strong><\/p>\n\n\n\n<pre class=\"wp-block-code\"><code>&gt; print(\"\\n=== \u5dee\u5206\u306e\u5dee\u5206\u6cd5\u306b\u3088\u308b\u56de\u5e30\u5206\u6790\u7d50\u679c ===\")\n&#91;1] \"\\n=== \u5dee\u5206\u306e\u5dee\u5206\u6cd5\u306b\u3088\u308b\u56de\u5e30\u5206\u6790\u7d50\u679c ===\"\n&gt; print(summary(model))\n\nCall:\nlm(formula = score ~ group_dummy * time_dummy, data = school_data_long)\n\nResiduals:\n    Min      1Q  Median      3Q     Max \n-17.730  -4.554  -0.330   4.808  19.870 \n\nCoefficients:\n                       Estimate Std. Error t value Pr(&gt;|t|)    \n(Intercept)              62.257      1.354  45.986   &lt;2e-16 ***\ngroup_dummy               4.170      1.915   2.178   0.0314 *  \ntime_dummy                2.273      1.915   1.187   0.2375    \ngroup_dummy:time_dummy    5.817      2.708   2.148   0.0338 *  \n---\nSignif. codes:  0 \u2018***\u2019 0.001 \u2018**\u2019 0.01 \u2018*\u2019 0.05 \u2018.\u2019 0.1 \u2018 \u2019 1\n\nResidual standard error: 7.415 on 116 degrees of freedom\nMultiple R-squared:  0.2866,    Adjusted R-squared:  0.2681 \nF-statistic: 15.53 on 3 and 116 DF,  p-value: 1.472e-08\n\n&gt; \n\n&gt; print(\"\\n=== \u5dee\u5206\u306e\u5dee\u5206\u306e\u624b\u52d5\u8a08\u7b97 ===\")\n&#91;1] \"\\n=== \u5dee\u5206\u306e\u5dee\u5206\u306e\u624b\u52d5\u8a08\u7b97 ===\"\n&gt; print(school_means)\n               group         time    score\n1   \u7d66\u98df\u7121\u511f\u5316\u5b9f\u65bd\u6821 \u7d66\u98df\u7121\u511f\u5316\u524d 66.42667\n2 \u7d66\u98df\u7121\u511f\u5316\u672a\u5b9f\u65bd\u6821 \u7d66\u98df\u7121\u511f\u5316\u524d 62.25667\n3   \u7d66\u98df\u7121\u511f\u5316\u5b9f\u65bd\u6821 \u7d66\u98df\u7121\u511f\u5316\u5f8c 74.51667\n4 \u7d66\u98df\u7121\u511f\u5316\u672a\u5b9f\u65bd\u6821 \u7d66\u98df\u7121\u511f\u5316\u5f8c 64.53000\n\n&gt; cat(sprintf(\"\\n\u7d66\u98df\u7121\u511f\u5316\u5b9f\u65bd\u6821\u306e\u5909\u5316: %.2f \u70b9\\n\", treatment_change))\n\u7d66\u98df\u7121\u511f\u5316\u5b9f\u65bd\u6821\u306e\u5909\u5316: 8.09 \u70b9\n&gt; cat(sprintf(\"\u7d66\u98df\u7121\u511f\u5316\u672a\u5b9f\u65bd\u6821\u306e\u5909\u5316: %.2f \u70b9\\n\", control_change))\n\u7d66\u98df\u7121\u511f\u5316\u672a\u5b9f\u65bd\u6821\u306e\u5909\u5316: 2.27 \u70b9\n&gt; cat(sprintf(\"\u5dee\u5206\u306e\u5dee\u5206\uff08\u624b\u52d5\u8a08\u7b97\uff09: %.2f \u70b9\\n\", did_manual))\n\u5dee\u5206\u306e\u5dee\u5206\uff08\u624b\u52d5\u8a08\u7b97\uff09: 5.82 \u70b9\n&gt; cat(sprintf(\"\u5dee\u5206\u306e\u5dee\u5206\uff08\u56de\u5e30\u4fc2\u6570\uff09: %.2f \u70b9\\n\", coef(model)&#91;\"group_dummy:time_dummy\"]))\n\u5dee\u5206\u306e\u5dee\u5206\uff08\u56de\u5e30\u4fc2\u6570\uff09: 5.82 \u70b9<\/code><\/pre>\n\n\n\n<h3 class=\"wp-block-heading\">\u7d50\u679c\u89e3\u91c8<\/h3>\n\n\n\n<p>\u5dee\u5206\u306e\u5dee\u5206\u6cd5\u306e\u7d50\u679c\u3092\u8a73\u3057\u304f\u89e3\u91c8\u3059\u308b\u3002\u7d50\u8ad6\u3068\u3057\u3066\u306f\u3001\u3053\u306e\u7d50\u679c\u306f\u3001\u7d66\u98df\u7121\u511f\u5316\u304c\u5150\u7ae5\u306e\u5b66\u7fd2\u6210\u7e3e\u5411\u4e0a\u306b\u6709\u52b9\u3067\u3042\u308b\u3053\u3068\u3092\u793a\u5506\u3057\u3066\u3044\u308b\u3002<\/p>\n\n\n\n<h4 class=\"wp-block-heading\">\u4fc2\u6570\u306e\u610f\u5473<\/h4>\n\n\n\n<h5 class=\"wp-block-heading\"><strong>\u5207\u7247\uff08Intercept\uff09: 62.26\u70b9<\/strong><\/h5>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u5bfe\u7167\u30b0\u30eb\u30fc\u30d7\uff08\u7d66\u98df\u7121\u511f\u5316\u672a\u5b9f\u65bd\u6821\uff09\u306e\u4ecb\u5165\u524d\u306e\u5e73\u5747\u5b66\u7fd2\u6210\u7e3e\u3067\u3042\u308b<\/li>\n\n\n\n<li>\u3053\u308c\u306f\u57fa\u6e96\u3068\u306a\u308b\u5024\u3067\u3042\u308b<\/li>\n<\/ul>\n\n\n\n<h5 class=\"wp-block-heading\"><strong>group_dummy: 4.17\u70b9<\/strong><\/h5>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u4ecb\u5165\u30b0\u30eb\u30fc\u30d7\u3068\u5bfe\u7167\u30b0\u30eb\u30fc\u30d7\u306e\u4ecb\u5165\u524d\u306e\u5b66\u7fd2\u6210\u7e3e\u5dee\u3067\u3042\u308b<\/li>\n\n\n\n<li>\u7d66\u98df\u7121\u511f\u5316\u5b9f\u65bd\u6821\u306f\u672a\u5b9f\u65bd\u6821\u3088\u308a\u4ecb\u5165\u524d\u306b4.17\u70b9\u9ad8\u304b\u3063\u305f<\/li>\n\n\n\n<li>\u3053\u308c\u306f\u9078\u629e\u30d0\u30a4\u30a2\u30b9\u3092\u793a\u3057\u3066\u304a\u308a\u3001\u5b9f\u65bd\u6821\u306e\u65b9\u304c\u5143\u3005\u6210\u7e3e\u304c\u826f\u304b\u3063\u305f\u53ef\u80fd\u6027\u304c\u3042\u308b<\/li>\n<\/ul>\n\n\n\n<h5 class=\"wp-block-heading\"><strong>time_dummy: 2.27\u70b9<\/strong><\/h5>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u5bfe\u7167\u30b0\u30eb\u30fc\u30d7\u306e\u4ecb\u5165\u524d\u5f8c\u306e\u5b66\u7fd2\u6210\u7e3e\u5909\u5316\u3067\u3042\u308b<\/li>\n\n\n\n<li>\u7d66\u98df\u7121\u511f\u5316\u672a\u5b9f\u65bd\u6821\u3067\u30822.27\u70b9\u306e\u5411\u4e0a\u304c\u3042\u3063\u305f<\/li>\n\n\n\n<li>\u3053\u308c\u306f\u6642\u9593\u52b9\u679c\uff08\u81ea\u7136\u306a\u5b66\u7fd2\u52b9\u679c\u3001\u4ed6\u306e\u8981\u56e0\u306b\u3088\u308b\u5411\u4e0a\uff09\u3092\u793a\u3059<\/li>\n<\/ul>\n\n\n\n<h5 class=\"wp-block-heading\"><strong>group_dummy:time_dummy: 5.82\u70b9<\/strong> &#x2b50;<\/h5>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>\u3053\u308c\u304c\u5dee\u5206\u306e\u5dee\u5206\u63a8\u5b9a\u91cf\uff08\u7d66\u98df\u7121\u511f\u5316\u306e\u7d14\u7c8b\u306a\u52b9\u679c\uff09\u3067\u3042\u308b<\/strong><\/li>\n\n\n\n<li>\u4ecb\u5165\u30b0\u30eb\u30fc\u30d7\u306e\u5909\u5316\uff088.09\u70b9\uff09\u304b\u3089\u5bfe\u7167\u30b0\u30eb\u30fc\u30d7\u306e\u5909\u5316\uff082.27\u70b9\uff09\u3092\u5f15\u3044\u305f\u5024\u3067\u3042\u308b<\/li>\n\n\n\n<li>\u7d66\u98df\u7121\u511f\u5316\u306b\u3088\u308a\u3001\u5b66\u7fd2\u6210\u7e3e\u304c5.82\u70b9\u5411\u4e0a\u3057\u305f<\/li>\n<\/ul>\n\n\n\n<h4 class=\"wp-block-heading\">\u7d71\u8a08\u7684\u6709\u610f\u6027<\/h4>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>group_dummy:time_dummy\uff085.82\u70b9\uff09<\/strong>: p = 0.0338 &lt; 0.05\n<ul class=\"wp-block-list\">\n<li>5%\u6c34\u6e96\u3067\u7d71\u8a08\u7684\u6709\u610f\u3067\u3042\u308b<\/li>\n\n\n\n<li>\u7d66\u98df\u7121\u511f\u5316\u306e\u52b9\u679c\u306f\u5076\u7136\u3067\u306f\u8aac\u660e\u3067\u304d\u306a\u3044<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>group_dummy\uff084.17\u70b9\uff09<\/strong>: p = 0.0314 &lt; 0.05\n<ul class=\"wp-block-list\">\n<li>\u4ecb\u5165\u524d\u306e\u9078\u629e\u30d0\u30a4\u30a2\u30b9\u3082\u6709\u610f\u3067\u3042\u308b<\/li>\n\n\n\n<li>\u5b9f\u65bd\u6821\u306e\u65b9\u304c\u5143\u3005\u6210\u7e3e\u304c\u826f\u304b\u3063\u305f<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>time_dummy\uff082.27\u70b9\uff09<\/strong>: p = 0.2375 &gt; 0.05\n<ul class=\"wp-block-list\">\n<li>\u6642\u9593\u52b9\u679c\u306f\u7d71\u8a08\u7684\u6709\u610f\u3067\u306f\u306a\u3044<\/li>\n\n\n\n<li>\u81ea\u7136\u306a\u5b66\u7fd2\u52b9\u679c\u306f\u660e\u78ba\u3067\u306f\u306a\u3044<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n\n\n\n<h4 class=\"wp-block-heading\">\u5dee\u5206\u306e\u5dee\u5206\uff1a\u624b\u52d5\u8a08\u7b97\u3068\u306e\u4e00\u81f4<\/h4>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u624b\u52d5\u8a08\u7b97: 5.82\u70b9<\/li>\n\n\n\n<li>\u56de\u5e30\u4fc2\u6570: 5.82\u70b9<\/li>\n\n\n\n<li>\u5b8c\u5168\u306b\u4e00\u81f4\u3057\u3066\u304a\u308a\u3001\u8a08\u7b97\u304c\u6b63\u3057\u3044\u3053\u3068\u3092\u78ba\u8a8d\u3067\u304d\u308b<\/li>\n<\/ul>\n\n\n\n<h4 class=\"wp-block-heading\">\u5b9f\u7528\u7684\u306a\u89e3\u91c8<\/h4>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>\u7d66\u98df\u7121\u511f\u5316\u306e\u52b9\u679c<\/strong>: \u5b66\u7fd2\u6210\u7e3e\u304c\u7d046\u70b9\u5411\u4e0a\u3059\u308b<\/li>\n\n\n\n<li><strong>\u52b9\u679c\u306e\u5927\u304d\u3055<\/strong>: 100\u70b9\u6e80\u70b9\u30676\u70b9\u306e\u5411\u4e0a\u306f\u5b9f\u7528\u7684\u306b\u610f\u5473\u306e\u3042\u308b\u52b9\u679c\u3067\u3042\u308b<\/li>\n\n\n\n<li><strong>\u653f\u7b56\u52b9\u679c<\/strong>: \u7d66\u98df\u7121\u511f\u5316\u306f\u5b66\u7fd2\u6210\u7e3e\u5411\u4e0a\u306b\u6709\u52b9\u306a\u653f\u7b56\u4ecb\u5165\u3067\u3042\u308b<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">\u6ce8\u610f\u70b9<\/h3>\n\n\n\n<ul class=\"wp-block-list\">\n<li>\u9078\u629e\u30d0\u30a4\u30a2\u30b9\uff084.17\u70b9\uff09\u304c\u5b58\u5728\u3059\u308b\u305f\u3081\u3001\u5b9f\u65bd\u6821\u306e\u65b9\u304c\u5143\u3005\u6210\u7e3e\u304c\u826f\u304b\u3063\u305f\u53ef\u80fd\u6027\u304c\u3042\u308b\uff08\u6700\u4e0a\u6bb5\u306e\u56f3\u53c2\u7167\uff09<\/li>\n\n\n\n<li>\u4e26\u884c\u30c8\u30ec\u30f3\u30c9\u306e\u4eee\u5b9a\u304c\u6e80\u305f\u3055\u308c\u3066\u3044\u308b\u304b\u78ba\u8a8d\u304c\u5fc5\u8981\u3067\u3042\u308b\uff08\u4ecb\u5165\u524d\u306e\u30c7\u30fc\u30bf\u3067\u78ba\u8a8d\u3059\u308b\u5fc5\u8981\u304c\u3042\u308b\uff09<\/li>\n\n\n\n<li>\u4ed6\u306e\u8981\u56e0\uff08\u6559\u5e2b\u306e\u8cea\u3001\u5bb6\u5ead\u74b0\u5883\u306a\u3069\uff09\u306e\u5f71\u97ff\u3092\u9664\u5916\u3067\u304d\u3066\u3044\u308b\u304b\u691c\u8a0e\u304c\u5fc5\u8981\u3067\u3042\u308b<\/li>\n<\/ul>\n\n\n\n<h2 class=\"wp-block-heading\">\u307e\u3068\u3081<\/h2>\n\n\n\n<p>\u5dee\u5206\u306e\u5dee\u5206\u6cd5\u306f\u3001\u9069\u5207\u306a\u6761\u4ef6\u4e0b\u3067\u3042\u308c\u3070\u3001\u653f\u7b56\u4ecb\u5165\u3084\u30d7\u30ed\u30b0\u30e9\u30e0\u306e\u52b9\u679c\u3092\u56e0\u679c\u7684\u306b\u63a8\u5b9a\u3059\u308b\u305f\u3081\u306e\u5f37\u529b\u306a\u30c4\u30fc\u30eb\u3060\u3002\u305d\u306e\u30b7\u30f3\u30d7\u30eb\u306a\u304c\u3089\u3082\u6d17\u7df4\u3055\u308c\u305f\u30a2\u30d7\u30ed\u30fc\u30c1\u306f\u3001\u7d4c\u6e08\u5b66\u3001\u516c\u8846\u885b\u751f\u5b66\u3001\u793e\u4f1a\u5b66\u306a\u3069\u3001\u69d8\u3005\u306a\u5206\u91ce\u3067\u6d3b\u7528\u3055\u308c\u3066\u3044\u308b\u3002<\/p>\n\n\n\n<p>\u3057\u304b\u3057\u3001DiD\u306e\u6709\u52b9\u6027\u306f<strong>\u4e26\u884c\u30c8\u30ec\u30f3\u30c9\u306e\u4eee\u5b9a<\/strong>\u306b\u5927\u304d\u304f\u4f9d\u5b58\u3059\u308b\u305f\u3081\u3001DiD\u3092\u9069\u7528\u3059\u308b\u969b\u306b\u306f\u3053\u306e\u4eee\u5b9a\u306e\u59a5\u5f53\u6027\u3092\u5341\u5206\u306b\u691c\u8a0e\u3059\u308b\u3053\u3068\u304c\u4e0d\u53ef\u6b20\u3060\u3002\u3053\u306e\u7406\u89e3\u304c\u6df1\u307e\u308c\u3070\u3001\u3088\u308a\u9069\u5207\u306a\u56e0\u679c\u63a8\u8ad6\u3092\u884c\u3046\u3053\u3068\u304c\u3067\u304d\u308b\u3088\u3046\u306b\u306a\u308b\u3060\u308d\u3046\u3002<\/p>\n\n\n\n\n","protected":false},"excerpt":{"rendered":"<p>\u5dee\u5206\u306e\u5dee\u5206\u6cd5\uff08Difference-in-Differences, DiD\uff09\u306f\u3001\u653f\u7b56\u5909\u66f4\u3084\u4ecb\u5165\u306e\u52b9\u679c\u3092\u8a55\u4fa1\u3059\u308b\u969b\u306b\u975e\u5e38\u306b\u5f37\u529b\u306a\u7d71\u8a08\u7684\u624b\u6cd5\u3060\u3002\u3053\u306e\u8a18\u4e8b\u3067\u306f\u3001DiD\u306e\u57fa\u672c\u7684\u306a\u8003\u3048\u65b9\u304b\u3089\u3001\u305d\u306e\u4f7f\u3044\u6240\u3001\u95a2\u9023\u3059\u308b\u7d71\u8a08\u624b\u6cd5\u3068\u306e\u9055\u3044\u3001 [&hellip;]<\/p>\n","protected":false},"author":2,"featured_media":4157,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"swell_btn_cv_data":"","_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":true,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2}},"categories":[111],"tags":[],"class_list":["post-4156","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-111"],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"https:\/\/best-biostatistics.com\/toukei-er\/wp-content\/uploads\/2025\/07\/Difference-in-difference_method-scaled.png","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/best-biostatistics.com\/toukei-er\/wp-json\/wp\/v2\/posts\/4156","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/best-biostatistics.com\/toukei-er\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/best-biostatistics.com\/toukei-er\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/best-biostatistics.com\/toukei-er\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/best-biostatistics.com\/toukei-er\/wp-json\/wp\/v2\/comments?post=4156"}],"version-history":[{"count":4,"href":"https:\/\/best-biostatistics.com\/toukei-er\/wp-json\/wp\/v2\/posts\/4156\/revisions"}],"predecessor-version":[{"id":4161,"href":"https:\/\/best-biostatistics.com\/toukei-er\/wp-json\/wp\/v2\/posts\/4156\/revisions\/4161"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/best-biostatistics.com\/toukei-er\/wp-json\/wp\/v2\/media\/4157"}],"wp:attachment":[{"href":"https:\/\/best-biostatistics.com\/toukei-er\/wp-json\/wp\/v2\/media?parent=4156"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/best-biostatistics.com\/toukei-er\/wp-json\/wp\/v2\/categories?post=4156"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/best-biostatistics.com\/toukei-er\/wp-json\/wp\/v2\/tags?post=4156"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}