{"id":9854,"date":"2026-09-30T12:26:01","date_gmt":"2026-09-30T03:26:01","guid":{"rendered":"https:\/\/since2020.jp\/media\/?p=9854"},"modified":"2026-09-30T12:39:36","modified_gmt":"2026-09-30T03:39:36","slug":"did-to-sdid","status":"publish","type":"post","link":"https:\/\/since2020.jp\/media\/did-to-sdid\/","title":{"rendered":"\u5dee\u5206\u306e\u5dee\u5206\u6cd5\uff08DID\uff09\uff1a\u57fa\u672c\u304b\u3089\u62e1\u5f35\u306eSDID\u307e\u3067"},"content":{"rendered":"\n

\u30a4\u30f3\u30c8\u30ed\u30c0\u30af\u30b7\u30e7\u30f3<\/h2>\n\n\n\n

\u30e9\u30f3\u30c0\u30e0\u5316\u6bd4\u8f03\u8a66\u9a13\uff08RCT\uff09\u304c\u7d44\u3081\u306a\u3044\u5834\u9762\u3067\u3001\u56e0\u679c\u52b9\u679c\u3092\u63a8\u5b9a\u3059\u308b\u305f\u3081\u306b\u3088\u304f\u4f7f\u308f\u308c\u308b\u624b\u6cd5\u306e\u4e00\u3064\u304c\u5dee\u5206\u306e\u5dee\u5206\u6cd5\uff08Difference-in-Differences, DID\uff09\u3067\u3042\u308b\u3002\u3042\u308b\u5730\u57df\u3060\u3051\u3067\u65b0\u3057\u3044\u653f\u7b56\u304c\u59cb\u307e\u3063\u305f\u3001\u3042\u308b\u5e97\u8217\u3060\u3051\u3067\u65b0\u30b5\u30fc\u30d3\u30b9\u3092\u5c0e\u5165\u3057\u305f\u3001\u3068\u3044\u3063\u305f\u300c\u81ea\u7136\u5b9f\u9a13\u300d\u306b\u8fd1\u3044\u72b6\u6cc1\u3067\u5a01\u529b\u3092\u767a\u63ee\u3059\u308b\u3002<\/p>\n\n\n\n

\u4f8b\u3048\u3070\u3001\u3042\u308bEC\u30b5\u30a4\u30c8\u304c\u7279\u5b9a\u306e\u90fd\u5e02\u3067\u3060\u3051\u9001\u6599\u7121\u6599\u30ad\u30e3\u30f3\u30da\u30fc\u30f3\u3092\u59cb\u3081\u305f\u3068\u3059\u308b\u3002\u305d\u306e\u30ad\u30e3\u30f3\u30da\u30fc\u30f3\u306b\u3069\u308c\u3060\u3051\u52b9\u679c\u304c\u3042\u3063\u305f\u304b\u3092\u77e5\u308a\u305f\u3044\u3068\u304d\u3001\u7d20\u6734\u306b\u306f\u300c\u30ad\u30e3\u30f3\u30da\u30fc\u30f3\u524d\u5f8c\u306e\u58f2\u4e0a\u3092\u6bd4\u3079\u308c\u3070\u3088\u3044\u300d\u3068\u601d\u3046\u304b\u3082\u3057\u308c\u306a\u3044\u3002\u3057\u304b\u3057\u3053\u308c\u306b\u306f\u843d\u3068\u3057\u7a74\u304c\u3042\u308b\u3002DID\u306f\u3001\u3053\u306e\u843d\u3068\u3057\u7a74\u3092\u56de\u907f\u3059\u308b\u305f\u3081\u306b\u751f\u307e\u308c\u305f\u624b\u6cd5\u3067\u3042\u308b\u3002<\/p>\n\n\n\n

\u306a\u305c\u5358\u7d14\u306a\u6bd4\u8f03\u3067\u306f\u30c0\u30e1\u306a\u306e\u304b<\/h2>\n\n\n\n

\u5148\u307b\u3069\u306e\u4f8b\u3067\u3001\u30ad\u30e3\u30f3\u30da\u30fc\u30f3\u524d\u5f8c\u306e\u58f2\u4e0a\u3092\u5358\u7d14\u306b\u6bd4\u3079\u308b\u65b9\u6cd5\u3092\u8003\u3048\u3066\u307f\u308b\u3002\u3082\u3057\u6bd4\u8f03\u671f\u9593\u306e\u9014\u4e2d\u3067\u30dc\u30fc\u30ca\u30b9\u671f\u306b\u5165\u3063\u3066\u3044\u305f\u3089\u3001\u30ad\u30e3\u30f3\u30da\u30fc\u30f3\u3092\u3057\u306a\u304f\u3066\u3082\u58f2\u4e0a\u306f\u4f38\u3073\u3066\u3044\u305f\u306f\u305a\u3067\u3042\u308b\u3002\u3064\u307e\u308a\u5358\u7d14\u306a\u524d\u5f8c\u6bd4\u8f03\u306f\u3001\u6642\u9593\u3068\u3068\u3082\u306b\u8d77\u304d\u308b\u4ed6\u306e\u5909\u5316\uff08\u5b63\u7bc0\u6027\u3001\u666f\u6c17\u3001\u7af6\u5408\u306e\u52d5\u304d\u306a\u3069\uff09\u3068\u3001\u65bd\u7b56\u306e\u52b9\u679c\u3092\u6df7\u540c\u3057\u3066\u3057\u307e\u3046\u3002<\/p>\n\n\n\n

\u3067\u306f\u3001\u30ad\u30e3\u30f3\u30da\u30fc\u30f3\u3092\u3057\u305f\u90fd\u5e02\u3068\u3001\u3057\u306a\u304b\u3063\u305f\u90fd\u5e02\u3092\u6bd4\u3079\u308c\u3070\u3088\u3044\u306e\u3060\u308d\u3046\u304b\u3002\u3053\u308c\u306b\u3082\u554f\u984c\u304c\u3042\u308b\u30022\u3064\u306e\u90fd\u5e02\u306f\u305d\u3082\u305d\u3082\u65bd\u7b56\u3068\u95a2\u4fc2\u306a\u304f\u58f2\u4e0a\u6c34\u6e96\u304c\u9055\u3046\u304b\u3082\u3057\u308c\u306a\u3044\u3002\u3053\u306e\u5dee\u3092\u300c\u65bd\u7b56\u306e\u52b9\u679c\u300d\u3068\u53d6\u308a\u9055\u3048\u3066\u3057\u307e\u3046\u3002<\/p>\n\n\n\n

DID\u306e\u30a2\u30a4\u30c7\u30a2\u306f\u30b7\u30f3\u30d7\u30eb\u3067\u3042\u308b\u3002\u300c\u4ecb\u5165\u7fa4\u306e\u524d\u5f8c\u5dee\u300d\u304b\u3089\u300c\u5bfe\u7167\u7fa4\u306e\u524d\u5f8c\u5dee\u300d\u3092\u5f15\u304d\u7b97\u3059\u308b\u3053\u3068\u3067\u3001\u6642\u9593\u30c8\u30ec\u30f3\u30c9\u306e\u5f71\u97ff\uff08\u4e21\u7fa4\u306b\u5171\u901a\u3057\u3066\u4e57\u308b\u5909\u5316\uff09\u3068\u3001\u305d\u3082\u305d\u3082\u306e\u6c34\u6e96\u5dee\uff08\u6642\u9593\u306b\u3088\u3089\u305a\u4e00\u5b9a\u306e\u5dee\uff09\u306e\u4e21\u65b9\u3092\u6253\u3061\u6d88\u3059\u3002\u6b8b\u308b\u306e\u304c\u65bd\u7b56\u305d\u306e\u3082\u306e\u306e\u52b9\u679c\u3001\u3068\u3044\u3046\u308f\u3051\u3067\u3042\u308b\u3002<\/p>\n\n\n\n

\u57fa\u672c\u306e\u6570\u5f0f<\/h2>\n\n\n\n

DID\u63a8\u5b9a\u91cf\u306f\u3001\u6b21\u306e\u3088\u3046\u306b\u5b9a\u7fa9\u3055\u308c\u308b\u3002<\/p>\n\n\n\n

\u03c4<\/mi>^<\/mo><\/mover><\/mtext>DID<\/mi><\/mrow><\/msub>=<\/mo>(<\/mo>Y<\/mi>\u203e<\/mo><\/mover>\u4ecb<\/mtext>\u5165<\/mtext>\u7fa4<\/mtext>,<\/mo>\u5f8c<\/mtext><\/mrow><\/msub>\u2212<\/mo>Y<\/mi>\u203e<\/mo><\/mover>\u4ecb<\/mtext>\u5165<\/mtext>\u7fa4<\/mtext>,<\/mo>\u524d<\/mtext><\/mrow><\/msub>)<\/mo><\/mrow>\u2212<\/mo>(<\/mo>Y<\/mi>\u203e<\/mo><\/mover>\u5bfe<\/mtext>\u7167<\/mtext>\u7fa4<\/mtext>,<\/mo>\u5f8c<\/mtext><\/mrow><\/msub>\u2212<\/mo>Y<\/mi>\u203e<\/mo><\/mover>\u5bfe<\/mtext>\u7167<\/mtext>\u7fa4<\/mtext>,<\/mo>\u524d<\/mtext><\/mrow><\/msub>)<\/mo><\/mrow><\/mrow>\\hat{\\tau}_{\\mathrm{DID}}\n=\n\\left(\\bar{Y}_{\\mathrm{\u4ecb\u5165\u7fa4,\u5f8c}}-\\bar{Y}_{\\mathrm{\u4ecb\u5165\u7fa4,\u524d}}\\right)\n–\n\\left(\\bar{Y}_{\\mathrm{\u5bfe\u7167\u7fa4,\u5f8c}}-\\bar{Y}_{\\mathrm{\u5bfe\u7167\u7fa4,\u524d}}\\right)<\/annotation><\/semantics><\/math><\/div>\n\n\n\n

\u5b9f\u52d9\u3067\u3088\u304f\u4f7f\u308f\u308c\u308b\u306e\u306f\u3001\u3053\u308c\u3068\u6570\u5b66\u7684\u306b\u540c\u5024\u306a\u56de\u5e30\u5f0f\u306b\u3088\u308b\u8868\u73fe\u3067\u3042\u308b\u3002<\/p>\n\n\n\n

Y<\/mi>i<\/mi>t<\/mi><\/mrow><\/msub>=<\/mo>\u03b2<\/mi>0<\/mn><\/msub>+<\/mo>\u03b2<\/mi>1<\/mn><\/msub><\/mtext>Treat<\/mi><\/mrow>i<\/mi><\/msub>+<\/mo>\u03b2<\/mi>2<\/mn><\/msub><\/mtext>Post<\/mi><\/mrow>t<\/mi><\/msub>+<\/mo>\u03b2<\/mi>3<\/mn><\/msub>(<\/mo><\/mtext>Treat<\/mi><\/mrow>i<\/mi><\/msub>\u00d7<\/mo><\/mtext>Post<\/mi><\/mrow>t<\/mi><\/msub>)<\/mo><\/mrow>+<\/mo>\u03b5<\/mi>i<\/mi>t<\/mi><\/mrow><\/msub><\/mrow>Y_{it}\n=\n\\beta_0\n+\\beta_1\\mathrm{Treat}_i\n+\\beta_2\\mathrm{Post}_t\n+\\beta_3\\left(\\mathrm{Treat}_i\\times\\mathrm{Post}_t\\right)\n+\\varepsilon_{it}<\/annotation><\/semantics><\/math><\/div>\n\n\n\n

\u3053\u3053\u3067 $\\mathrm{Treat}_i$ \u306f\u500b\u4f53 $i$ \u304c\u4ecb\u5165\u7fa4\u306a\u30891\u3001$\\mathrm{Post}_t$ \u306f\u6642\u671f $t$ \u304c\u4ecb\u5165\u5f8c\u306a\u30891\u3092\u53d6\u308b\u30c0\u30df\u30fc\u5909\u6570\u3067\u3042\u308b\u3002\u3053\u306e\u4ea4\u5dee\u9805\u306e\u4fc2\u6570 $\\beta_3$ \u304cDID\u63a8\u5b9a\u91cf\u305d\u306e\u3082\u306e\u3067\u3042\u308a\u3001\u30b3\u30f3\u30c8\u30ed\u30fc\u30eb\u5909\u6570\u3092\u8db3\u3057\u305f\u308a\u3001\u6a19\u6e96\u8aa4\u5dee\u3092\u30af\u30e9\u30b9\u30bf\u30ea\u30f3\u30b0\u3057\u305f\u308a\u3068\u3044\u3063\u305f\u62e1\u5f35\u304c\u3057\u3084\u3059\u3044\u305f\u3081\u3001\u56de\u5e30\u306e\u5f62\u3067\u5b9f\u88c5\u3055\u308c\u308b\u3053\u3068\u304c\u591a\u3044\u3002<\/p>\n\n\n\n

\u5177\u4f53\u4f8b\u3067\u8a08\u7b97\u3057\u3066\u307f\u308b<\/h2>\n\n\n\n

\u9001\u6599\u7121\u6599\u30ad\u30e3\u30f3\u30da\u30fc\u30f3\u3092A\u5e02\uff08\u4ecb\u5165\u7fa4\uff09\u3067\u5b9f\u65bd\u3057\u3001\u4f3c\u305f\u898f\u6a21\u306eB\u5e02\uff08\u5bfe\u7167\u7fa4\uff09\u306f\u5b9f\u65bd\u3057\u306a\u304b\u3063\u305f\u3068\u3059\u308b\u3002\u305d\u308c\u305e\u308c\u306e\u6708\u9593\u58f2\u4e0a\uff08\u5358\u4f4d\uff1a\u767e\u4e07\u5186\uff09\u304c\u6b21\u306e\u3088\u3046\u306b\u306a\u3063\u305f\u3068\u3057\u3088\u3046\u3002<\/p>\n\n\n\n

<\/th>\u4ecb\u5165\u524d<\/th>\u4ecb\u5165\u5f8c<\/th>\u5dee\uff08\u5f8c\u2212\u524d\uff09<\/th><\/tr><\/thead>
A\u5e02\uff08\u4ecb\u5165\u7fa4\uff09<\/td>50<\/td>90<\/td>+40<\/td><\/tr>
B\u5e02\uff08\u5bfe\u7167\u7fa4\uff09<\/td>60<\/td>70<\/td>+10<\/td><\/tr>
\u5dee\u5206\u306e\u5dee\uff08DID\uff09<\/td><\/td><\/td>+30<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n

A\u5e02\u306e\u58f2\u4e0a\u306f40\u4f38\u3073\u3066\u3044\u308b\u304c\u3001\u305d\u306e\u3046\u306110\u306f\uff08B\u5e02\u3082\u540c\u3058\u3088\u3046\u306b\u4f38\u3073\u3066\u3044\u308b\u3053\u3068\u304b\u3089\u5206\u304b\u308b\uff09\u5e02\u5834\u5168\u4f53\u306e\u8ffd\u3044\u98a8\u306b\u3088\u308b\u3082\u306e\u3067\u3042\u308a\u3001\u30ad\u30e3\u30f3\u30da\u30fc\u30f3\u81ea\u4f53\u306b\u3088\u308b\u62bc\u3057\u4e0a\u3052\u52b9\u679c\u306f 40 \u2212 10 = 30 \u3068\u63a8\u5b9a\u3055\u308c\u308b\u3002<\/p>\n\n\n\n

\u30b0\u30e9\u30d5\u3067\u898b\u308bDID<\/h2>\n\n\n\n

DID\u306f\u6298\u308c\u7dda\u30b0\u30e9\u30d5\u306b\u63cf\u304f\u3068\u76f4\u611f\u7684\u306b\u7406\u89e3\u3057\u3084\u3059\u3044\u3002\u4ecb\u5165\u524d\u306e\u671f\u9593\u306f\u4e21\u7fa4\u3068\u3082\u540c\u3058\u50be\u304d\u3067\u4f38\u3073\u3066\u304a\u308a\uff08\u5e73\u884c\u306a\u30c8\u30ec\u30f3\u30c9\uff09\u3001\u4ecb\u5165\u5f8c\u306b\u4ecb\u5165\u7fa4\u3060\u3051\u304c\u4e0a\u306b\u8df3\u306d\u4e0a\u304c\u308b\u3002\u3082\u3057\u4ecb\u5165\u304c\u306a\u304b\u3063\u305f\u3089\u4ecb\u5165\u7fa4\u306f\u3069\u3046\u306a\u3063\u3066\u3044\u305f\u304b\u3001\u3068\u3044\u3046\u300c\u53cd\u5b9f\u4eee\u60f3\u300d\u3092\u3001\u5bfe\u7167\u7fa4\u3068\u540c\u3058\u50be\u304d\u306e\u70b9\u7dda\u3067\u5ef6\u9577\u3059\u308b\u3068\u3001\u5b9f\u6e2c\u5024\u3068\u306e\u9593\u306b\u30ae\u30e3\u30c3\u30d7\u304c\u751f\u307e\u308c\u308b\u3002\u3053\u306e\u30ae\u30e3\u30c3\u30d7\u304cDID\u63a8\u5b9a\u5024\u3067\u3042\u308b\u3002<\/p>\n\n\n\n

\"\"<\/figure>\n\n\n\n

\u56f31: \u4ecb\u5165\u524d\u306f2\u7fa4\u3068\u3082\u5e73\u884c\u306b\u63a8\u79fb\u3059\u308b\u3002\u4ecb\u5165\u7fa4\u306e\u5b9f\u6e2c\u5024\uff08\u7d2b\u306e\u5b9f\u7dda\uff09\u3068\u3001\u5bfe\u7167\u7fa4\u3068\u540c\u3058\u50be\u304d\u3067\u4f38\u3073\u305f\u3068\u4eee\u5b9a\u3057\u305f\u53cd\u5b9f\u4eee\u60f3\uff08\u7d2b\u306e\u70b9\u7dda\uff09\u3068\u306e\u30ae\u30e3\u30c3\u30d7\u304cDID\u63a8\u5b9a\u5024\u306b\u306a\u308b\u3002<\/p>\n\n\n\n

\u5e73\u884c\u30c8\u30ec\u30f3\u30c9\u306e\u4eee\u5b9a<\/h2>\n\n\n\n

DID\u304c\u6210\u308a\u7acb\u3064\u305f\u3081\u306e\u6838\u5fc3\u7684\u306a\u4eee\u5b9a\u306f\u5e73\u884c\u30c8\u30ec\u30f3\u30c9\u306e\u4eee\u5b9a\uff08Parallel Trends Assumption\uff09\u3067\u3042\u308b\u3002\u300c\u3082\u3057\u4ecb\u5165\u7fa4\u304c\u4ecb\u5165\u3092\u53d7\u3051\u306a\u304b\u3063\u305f\u306a\u3089\u3001\u5bfe\u7167\u7fa4\u3068\u307e\u3063\u305f\u304f\u540c\u3058\u30c8\u30ec\u30f3\u30c9\u3092\u8fbf\u3063\u3066\u3044\u305f\u306f\u305a\u3060\u300d\u3068\u3044\u3046\u4eee\u5b9a\u3067\u3042\u308a\u3001\u3053\u308c\u304c\u5d29\u308c\u3066\u3044\u308b\u3068\u56f31\u306e\u53cd\u5b9f\u4eee\u60f3\u306e\u70b9\u7dda\u304c\u8aa4\u3063\u305f\u4f4d\u7f6e\u306b\u5f15\u304b\u308c\u3001DID\u63a8\u5b9a\u5024\u306b\u30d0\u30a4\u30a2\u30b9\u304c\u4e57\u308b\u3002<\/p>\n\n\n\n

\u3053\u306e\u4eee\u5b9a\u306f\u30c7\u30fc\u30bf\u304b\u3089\u5b8c\u5168\u306b\u8a3c\u660e\u3059\u308b\u3053\u3068\u306f\u3067\u304d\u306a\u3044\u304c\u3001\u9593\u63a5\u7684\u306b\u88cf\u4ed8\u3051\u308b\u3053\u3068\u306f\u3067\u304d\u308b\u3002\u4ee3\u8868\u7684\u306a\u306e\u304c\u6b21\u306e2\u3064\u3067\u3042\u308b\u3002<\/p>\n\n\n\n

    \n
  • \u30d7\u30ec\u30c8\u30ec\u30f3\u30c9\u306e\u78ba\u8a8d\uff1a \u4ecb\u5165\u524d\u306e\u8907\u6570\u671f\u9593\u306b\u3064\u3044\u3066\u3001\u4ecb\u5165\u7fa4\u3068\u5bfe\u7167\u7fa4\u306e\u63a8\u79fb\u304c\u5b9f\u969b\u306b\u5e73\u884c\u3060\u3063\u305f\u304b\u3092\u78ba\u8a8d\u3059\u308b\u3002\u56f31\u3067\u3044\u3048\u3070\u300c2\u671f\u524d\u2192\u4ecb\u5165\u76f4\u524d\u300d\u306e\u50be\u304d\u304c\u4e21\u7fa4\u3067\u305d\u308d\u3063\u3066\u3044\u308b\u304b\u3092\u898b\u308b\u3002\u3053\u3053\u304c\u5e73\u884c\u3067\u306a\u3051\u308c\u3070\u3001\u4ecb\u5165\u5f8c\u306e\u5e73\u884c\u30c8\u30ec\u30f3\u30c9\u4eee\u5b9a\u3082\u7591\u308f\u3057\u304f\u306a\u308b\u3002<\/li>\n\n\n\n
  • \u30d7\u30e9\u30bb\u30dc\u30c6\u30b9\u30c8\uff1a \u5b9f\u969b\u306b\u306f\u4f55\u3082\u8d77\u304d\u3066\u3044\u306a\u3044\u67b6\u7a7a\u306e\u6642\u70b9\u3092\u300c\u4ecb\u5165\u6642\u70b9\u300d\u3060\u3068\u4eee\u5b9a\u3057\u3066DID\u3092\u8a08\u7b97\u3057\u3001\u52b9\u679c\u304c\u30bc\u30ed\u306b\u8fd1\u3044\u3053\u3068\u3092\u78ba\u8a8d\u3059\u308b\u3002\u6709\u610f\u306a\u300c\u52b9\u679c\u300d\u304c\u51fa\u3066\u3057\u307e\u3046\u5834\u5408\u3001\u5e73\u884c\u30c8\u30ec\u30f3\u30c9\u306e\u4eee\u5b9a\u306b\u7591\u3044\u304c\u751f\u3058\u308b\u3002<\/li>\n<\/ul>\n\n\n\n

    \u62e1\u5f35<\/h2>\n\n\n\n

    \u524d\u7ae0\u3067\u898b\u305f\u901a\u308a\u3001DID\u306e\u6210\u5426\u306f\u5e73\u884c\u30c8\u30ec\u30f3\u30c9\u306e\u4eee\u5b9a\u306b\u304b\u304b\u3063\u3066\u3044\u308b\u3002\u3057\u304b\u3057\u73fe\u5b9f\u306b\u306f\u3001\u4f7f\u3048\u308b\u5bfe\u7167\u7fa4\u306e\u63a8\u79fb\u304c\u4ecb\u5165\u7fa4\u306e\u4e8b\u524d\u30c8\u30ec\u30f3\u30c9\u3068\u3074\u3063\u305f\u308a\u5e73\u884c\u3068\u306f\u9650\u3089\u306a\u3044\u3002\u3053\u306e\u5f31\u70b9\u306b\u5bfe\u5fdc\u3059\u308b\u62e1\u5f35\u3068\u3057\u3066\u8fd1\u5e74\u6ce8\u76ee\u3055\u308c\u3066\u3044\u308b\u306e\u304cSynthetic Difference-in-Differences\uff08SDID\uff09\u3067\u3042\u308b\u3002<\/p>\n\n\n\n

    \u5408\u6210\u30b3\u30f3\u30c8\u30ed\u30fc\u30eb\u6cd5\uff08Synthetic Control Method\uff09<\/h3>\n\n\n\n

    SDID\u306e\u571f\u53f0\u306b\u306f\u3001\u5408\u6210\u30b3\u30f3\u30c8\u30ed\u30fc\u30eb\u6cd5\uff08Synthetic Control Method, SCM\uff09\u3068\u3044\u3046\u5225\u306e\u624b\u6cd5\u304c\u3042\u308b\u3002SCM\u306f\u3001\u5358\u4e00\u306e\u5bfe\u7167\u7fa4\u3092\u305d\u306e\u307e\u307e\u4f7f\u3046\u4ee3\u308f\u308a\u306b\u3001\u8907\u6570\u306e\u5019\u88dc\u5730\u57df\uff08\u4f8b\u3048\u3070\u4ecb\u5165\u306e\u306a\u304b\u3063\u305f\u4ed6\u306e\u90fd\u9053\u5e9c\u770c\uff09\u306b\u91cd\u307f $\\omega_i$ \u3092\u4ed8\u3051\u3066\u8db3\u3057\u5408\u308f\u305b\u3001\u300c\u4ecb\u5165\u524d\u306e\u63a8\u79fb\u304c\u4ecb\u5165\u7fa4\u3068\u6700\u3082\u3088\u304f\u4e00\u81f4\u3059\u308b\u5408\u6210\u5bfe\u7167\u7fa4\u300d\u3092\u4eba\u5de5\u7684\u306b\u4f5c\u308a\u51fa\u3059\u3002\u5e73\u884c\u3067\u306a\u3044\u5bfe\u7167\u7fa4\u3057\u304b\u624b\u5143\u306b\u306a\u304f\u3066\u3082\u3001\u8907\u6570\u3092\u7d44\u307f\u5408\u308f\u305b\u308b\u3053\u3068\u3067\u5e73\u884c\u306b\u8fd1\u3044\u30c8\u30ec\u30f3\u30c9\u3092\u4f5c\u308c\u308b\u306e\u304c\u5229\u70b9\u3067\u3042\u308b\u3002<\/p>\n\n\n\n

    \u305f\u3060\u3057SCM\u306b\u306f\u5f31\u70b9\u3082\u3042\u308b\u3002SCM\u306f\u6c34\u6e96\uff08\u30ec\u30d9\u30eb\uff09\u3092\u5408\u308f\u305b\u308b\u3053\u3068\u306b\u4e3b\u773c\u3092\u7f6e\u3044\u3066\u304a\u308a\u3001DID\u306e\u3088\u3046\u306a\u300c\u524d\u5f8c\u306e\u5dee\u300d\u3092\u53d6\u308b\u64cd\u4f5c\u3092\u3057\u306a\u3044\u305f\u3081\u3001\u4ecb\u5165\u7fa4\u306b\u3082\u3068\u3082\u3068\u5b58\u5728\u3059\u308b\u6642\u9593\u4e0d\u5909\u306e\u30ba\u30ec\uff08\u30c8\u30ec\u30f3\u30c9\u306b\u306f\u5f71\u97ff\u3057\u306a\u3044\u304c\u6c34\u6e96\u306b\u306f\u52b9\u3044\u3066\u304f\u308b\u8981\u56e0\uff09\u304c\u6b8b\u3063\u3066\u3057\u307e\u3046\u5834\u5408\u304c\u3042\u308b\u3002<\/p>\n\n\n\n

    SDID\uff1a\u4e21\u8005\u306e\u3044\u3044\u3068\u3053\u53d6\u308a<\/h3>\n\n\n\n

    SDID\uff08Arkhangelsky et al., 2021\uff09\u306f\u3001DID\u306e\u300c\u5dee\u5206\u3092\u53d6\u308b\u3053\u3068\u3067\u6642\u9593\u4e0d\u5909\u306e\u8981\u56e0\u3092\u6d88\u3059\u300d\u3068\u3044\u3046\u5f37\u307f\u3068\u3001SCM\u306e\u300c\u91cd\u307f\u4ed8\u3051\u3067\u4e8b\u524d\u30c8\u30ec\u30f3\u30c9\u3092\u63c3\u3048\u308b\u300d\u3068\u3044\u3046\u5f37\u307f\u3092\u7d44\u307f\u5408\u308f\u305b\u308b\u3002\u5177\u4f53\u7684\u306b\u306f\u3001\u5bfe\u7167\u7fa4\u306b\u5bfe\u3059\u308b\u500b\u4f53\u306e\u91cd\u307f $\\omega_i$\uff08\u4ecb\u5165\u524d\u306e\u63a8\u79fb\u304c\u4ecb\u5165\u7fa4\u306b\u8fd1\u3044\u5bfe\u7167\u7fa4\u307b\u3069\u5927\u304d\u306a\u91cd\u307f\u3092\u6301\u3064\uff09\u3068\u3001\u6642\u70b9\u306e\u91cd\u307f $\\lambda_t$\uff08\u4ecb\u5165\u5f8c\u306e\u671f\u9593\u3068\u985e\u4f3c\u3057\u305f\u63a8\u79fb\u3092\u3057\u3066\u3044\u308b\u4ecb\u5165\u524d\u306e\u6642\u70b9\u307b\u3069\u5927\u304d\u306a\u91cd\u307f\u3092\u6301\u3064\uff09\u306e\u4e21\u65b9\u3092\u63a8\u5b9a\u3057\u305f\u4e0a\u3067\u3001\u91cd\u307f\u4ed8\u304d\u306eDID\u56de\u5e30\u3092\u884c\u3046\u3002<\/p>\n\n\n\n

    \n
    \u03c4<\/mi>^<\/mo><\/mover><\/mtext>SDID<\/mi><\/mrow><\/msub>=<\/mo>arg\u2009min<\/mi>\u03c4<\/mi>,<\/mo>\u03bc<\/mi>,<\/mo>\ud835\udf36<\/mi>,<\/mo>\ud835\udf37<\/mi><\/mrow><\/munder>\u2061<\/mo><\/mspace>\u2211<\/mo>i<\/mi>,<\/mo>t<\/mi><\/mrow><\/munder><\/mrow>(<\/mo>Y<\/mi>i<\/mi>t<\/mi><\/mrow><\/msub>\u2212<\/mo>\u03bc<\/mi>\u2212<\/mo>\u03b1<\/mi>i<\/mi><\/msub>\u2212<\/mo>\u03b2<\/mi>t<\/mi><\/msub>\u2212<\/mo>W<\/mi>i<\/mi>t<\/mi><\/mrow><\/msub>\u03c4<\/mi>)<\/mo><\/mrow>2<\/mn><\/msup>\u03c9<\/mi>^<\/mo><\/mover>i<\/mi><\/msub>\u03bb<\/mi>^<\/mo><\/mover>t<\/mi><\/msub><\/mrow>\\hat{\\tau}_{\\mathrm{SDID}}\n=\n\\operatorname*{arg\\,min}_{\\tau,\\mu,\\boldsymbol{\\alpha},\\boldsymbol{\\beta}}\n\\sum_{i,t}\n\\left(Y_{it}-\\mu-\\alpha_i-\\beta_t-W_{it}\\tau\\right)^2\n\\hat{\\omega}_i\\hat{\\lambda}_t<\/annotation><\/semantics><\/math><\/div>\n<\/div><\/div>\n\n\n\n

    \u3053\u3053\u3067 $\\alpha_i$\u30fb$\\beta_t$ \u306f\u500b\u4f53\u30fb\u6642\u70b9\u306e\u56fa\u5b9a\u52b9\u679c\u3001$W_{it}$ \u306f\u4ecb\u5165\u3092\u53d7\u3051\u305f\u304b\u3069\u3046\u304b\u306e\u30c0\u30df\u30fc\u3067\u3042\u308b\u3002\u91cd\u307f $\\hat{\\omega}_i,\\hat{\\lambda}_t$ \u3092\u901a\u5e38\u306eDID\uff08\u5168\u5bfe\u7167\u7fa4\u30fb\u5168\u671f\u9593\u3092\u7b49\u3057\u304f\u6271\u3046\uff09\u304b\u3089\u6700\u9069\u5316\u3057\u76f4\u3059\u3053\u3068\u3067\u3001\u7d20\u6734\u306aDID\u3088\u308a\u4e8b\u524d\u30c8\u30ec\u30f3\u30c9\u306e\u30ba\u30ec\u306b\u9811\u5065\u306b\u306a\u308a\u3001\u304b\u3064SCM\u3088\u308a\u5909\u52d5\uff08\u5206\u6563\uff09\u306e\u5c11\u306a\u3044\u5b89\u5b9a\u3057\u305f\u63a8\u5b9a\u91cf\u306b\u306a\u308b\u3053\u3068\u304c\u793a\u3055\u308c\u3066\u3044\u308b\u3002<\/p>\n\n\n\n

      \n
    • \u5411\u3044\u3066\u3044\u308b\u5834\u9762\uff1a \u4ecb\u5165\u7fa4\u304c1\u3064\u304b\u5c11\u6570\u3067\u3001\u5019\u88dc\u3068\u306a\u308b\u5bfe\u7167\u7fa4\uff08\u90fd\u9053\u5e9c\u770c\u3001\u5e97\u8217\u3001\u4f01\u696d\u306a\u3069\uff09\u304c\u591a\u6570\u3042\u308b\u30b1\u30fc\u30b9\u3002\u30df\u30cb\u30de\u30e0\u30a6\u30a7\u30a4\u30b8\u306e\u52b9\u679c\u5206\u6790\u306a\u3069\u3001\u653f\u7b56\u8a55\u4fa1\u306e\u6587\u8108\u3067\u7279\u306b\u4f7f\u308f\u308c\u308b\u3002<\/li>\n\n\n\n
    • \u5e73\u884c\u30c8\u30ec\u30f3\u30c9\u306e\u4eee\u5b9a\u304c\u7de9\u548c\u3055\u308c\u308b\uff1a \u624b\u5143\u306e\u5bfe\u7167\u7fa4\u304c\u305d\u306e\u307e\u307e\u3067\u306f\u5e73\u884c\u3067\u306a\u304f\u3066\u3082\u3001\u91cd\u307f\u4ed8\u3051\u306b\u3088\u3063\u3066\u300c\u4ecb\u5165\u7fa4\u306b\u4f3c\u305f\u52d5\u304d\u3092\u3059\u308b\u5408\u6210\u5bfe\u7167\u7fa4\u300d\u3092\u4f5c\u308c\u308b\u305f\u3081\u3001\u4eee\u5b9a\u304c\u3084\u3084\u7de9\u304f\u306a\u308b\u3002<\/li>\n\n\n\n
    • \u63a8\u8ad6\uff1a \u30d7\u30e9\u30bb\u30dc\u6cd5\u3084\u30b8\u30e3\u30c3\u30af\u30ca\u30a4\u30d5\u6cd5\u306b\u3088\u308b\u6a19\u6e96\u8aa4\u5dee\u306e\u63a8\u5b9a\u65b9\u6cd5\u304c\u4f75\u305b\u3066\u63d0\u6848\u3055\u308c\u3066\u304a\u308a\u3001\u4fe1\u983c\u533a\u9593\u306e\u69cb\u7bc9\u3082\u30b5\u30dd\u30fc\u30c8\u3055\u308c\u3066\u3044\u308b\u3002<\/li>\n<\/ul>\n\n\n\n

      \u307e\u3068\u3081<\/h2>\n\n\n\n
        \n
      • DID\u306f\u300c\u4ecb\u5165\u7fa4\u306e\u524d\u5f8c\u5dee\u300d\u304b\u3089\u300c\u5bfe\u7167\u7fa4\u306e\u524d\u5f8c\u5dee\u300d\u3092\u5f15\u304f\u3053\u3068\u3067\u3001\u6642\u9593\u30c8\u30ec\u30f3\u30c9\u3068\u7fa4\u9593\u306e\u3082\u3068\u3082\u3068\u306e\u6c34\u6e96\u5dee\u3092\u540c\u6642\u306b\u53d6\u308a\u9664\u304f\u624b\u6cd5\u3067\u3042\u308b\u3002<\/li>\n\n\n\n
      • \u56de\u5e30\u5f0f\u3067\u306f\u3001Treat\u00d7Post\u306e\u4ea4\u5dee\u9805\u306e\u4fc2\u6570\u304cDID\u63a8\u5b9a\u91cf\u306b\u5bfe\u5fdc\u3059\u308b\u3002<\/li>\n\n\n\n
      • \u6210\u7acb\u306e\u9375\u306f\u5e73\u884c\u30c8\u30ec\u30f3\u30c9\u306e\u4eee\u5b9a\u3067\u3042\u308a\u3001\u30d7\u30ec\u30c8\u30ec\u30f3\u30c9\u306e\u78ba\u8a8d\u3084\u30d7\u30e9\u30bb\u30dc\u30c6\u30b9\u30c8\u3067\u9593\u63a5\u7684\u306b\u88cf\u4ed8\u3051\u308b\u3002<\/li>\n\n\n\n
      • \u4ecb\u5165\u306e\u30bf\u30a4\u30df\u30f3\u30b0\u304c\u7fa4\u3054\u3068\u306b\u7570\u306a\u308b\u73fe\u5b9f\u306e\u30c7\u30fc\u30bf\u3067\u306f\u3001\u5358\u7d14\u306a\u4e8c\u5143\u56fa\u5b9a\u52b9\u679c\u30e2\u30c7\u30eb\u304c\u30d0\u30a4\u30a2\u30b9\u3092\u6301\u3064\u5834\u5408\u304c\u3042\u308a\u3001\u8fd1\u5e74\u306f\u3088\u308a\u9811\u5065\u306a\u63a8\u5b9a\u91cf\u304c\u63d0\u6848\u3055\u308c\u3066\u3044\u308b\u3002<\/li>\n<\/ul>\n","protected":false},"excerpt":{"rendered":"

        \u30a4\u30f3\u30c8\u30ed\u30c0\u30af\u30b7\u30e7\u30f3 \u30e9\u30f3\u30c0\u30e0\u5316\u6bd4\u8f03\u8a66\u9a13\uff08RCT\uff09\u304c\u7d44\u3081\u306a\u3044\u5834\u9762\u3067\u3001\u56e0\u679c\u52b9\u679c\u3092\u63a8\u5b9a\u3059\u308b\u305f\u3081\u306b\u3088\u304f\u4f7f\u308f\u308c\u308b\u624b\u6cd5\u306e\u4e00\u3064\u304c\u5dee\u5206\u306e\u5dee\u5206\u6cd5\uff08Difference-in-Differences, DID\uff09\u3067\u3042\u308b\u3002\u3042\u308b\u5730\u57df\u3060\u3051\u3067\u65b0\u3057\u3044\u653f […]<\/p>\n","protected":false},"author":77,"featured_media":8355,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"content-type":"","swell_btn_cv_data":"","footnotes":"","_wp_rev_ctl_limit":""},"categories":[1251],"tags":[39,33,35],"class_list":["post-9854","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-data-analysis","tag-39","tag-33","tag-35"],"_links":{"self":[{"href":"https:\/\/since2020.jp\/media\/wp-json\/wp\/v2\/posts\/9854","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/since2020.jp\/media\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/since2020.jp\/media\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/since2020.jp\/media\/wp-json\/wp\/v2\/users\/77"}],"replies":[{"embeddable":true,"href":"https:\/\/since2020.jp\/media\/wp-json\/wp\/v2\/comments?post=9854"}],"version-history":[{"count":8,"href":"https:\/\/since2020.jp\/media\/wp-json\/wp\/v2\/posts\/9854\/revisions"}],"predecessor-version":[{"id":9871,"href":"https:\/\/since2020.jp\/media\/wp-json\/wp\/v2\/posts\/9854\/revisions\/9871"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/since2020.jp\/media\/wp-json\/wp\/v2\/media\/8355"}],"wp:attachment":[{"href":"https:\/\/since2020.jp\/media\/wp-json\/wp\/v2\/media?parent=9854"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/since2020.jp\/media\/wp-json\/wp\/v2\/categories?post=9854"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/since2020.jp\/media\/wp-json\/wp\/v2\/tags?post=9854"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}