{"id":3796,"date":"2021-04-22T21:23:27","date_gmt":"2021-04-22T13:23:27","guid":{"rendered":"http:\/\/www.sniper97.cn\/?p=3796"},"modified":"2021-04-22T21:23:27","modified_gmt":"2021-04-22T13:23:27","slug":"%e3%80%90%e6%b7%b1%e5%ba%a6%e5%ad%a6%e4%b9%a0%e7%ac%94%e8%ae%b0%e3%80%91%e6%bf%80%e6%b4%bb%e5%87%bd%e6%95%b0%e4%b8%8e%e6%8d%9f%e5%a4%b1%e5%87%bd%e6%95%b0","status":"publish","type":"post","link":"http:\/\/www.sniper97.cn\/index.php\/note\/deep-learning\/note-deep-learning\/3796\/","title":{"rendered":"\u3010\u6df1\u5ea6\u5b66\u4e60\u7b14\u8bb0\u3011\u6fc0\u6d3b\u51fd\u6570\u4e0e\u635f\u5931\u51fd\u6570"},"content":{"rendered":"\n<p>\u8fd9\u7bc7\u6587\u7ae0\u8ba8\u8bbabinary_crossentropy\u3001(sparse)categorical_crossentropy\u7684\u533a\u522b \u8fd8\u6709 sigmoid\u548csoftmax 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class=\"wp-image-3800\"\/><\/figure><\/div>\n\n\n<p>\u53ef\u4ee5\u5f88\u660e\u663e\u7684\u770b\u51fa\u6765\uff0c\u5f53y\u4e3a0\u65f6\uff0c\u635f\u5931\u51fd\u6570\u4e3a0\u3002\u8fd9\u5c31\u610f\u5473\u7740\uff0c\u5f53\u6837\u672c\u4e3a0\u65f6\uff0c\u6a21\u578b\u6ca1\u6709\u529e\u6cd5\u6b63\u786e\u5b66\u4e60\uff08\u4e5f\u5c31\u662f\u8bf4\uff0cCE\u7684\u6838\u5fc3\u662f\u5b66\u4e60\u6b63\u6837\u672c\uff0c\u7136\u540e\u901a\u8fc7softmax\u6291\u5236\u8d1f\u6837\u672c\u7684\u503c\uff09\uff0c\u56e0\u6b64\uff1a<\/p>\n\n\n<p>\u7531\u4e8e\u4f7f\u7528\u4e86\u5355\u8282\u70b9\uff0cCE\u6ca1\u6709\u529e\u6cd5\u5b66\u4e60\u8d1f\u6837\u672c\uff0c\u53ea\u80fd\u662f\u968f\u673a\u8f93\u51fa\uff0c\u800c\u6b63\u6837\u672c\u7684\u51c6\u786e\u7387\uff08precision\uff09\u4f1a\u5f88\u9ad8\u3002<\/p>\n\n\n<p>\u6211\u4eec\u4f7f\u7528imdb\u8fdb\u884c\u6d4b\u8bd5\uff1a<\/p>\n\n\n<pre class=\"wp-block-code\"><code>\u8fd0\u884c200\u4e2astep\u540e\uff0cbinary_crossentropy\u5df2\u7ecf\u660e\u663e\u6536\u655b\uff1a\n20000\/25000 [==>......] - ETA: 1:53 - loss: 0.5104 - acc: 0.7282\n\u800ccategorical_crossentropy\u5374\u6536\u655b\u7f13\u6162\uff1a\n20000\/25000 [==>......] - ETA: 1:58 - loss: 5.9557e-08 - acc: 0.5005<\/code><\/pre>\n\n\n<p>\u53ef\u4ee5\u9a8c\u8bc1\u8fd9\u4e2a\u731c\u60f3\u3002<\/p>\n\n\n<p>\u800c\u4e8b\u5b9e\u4e0a\uff0ctensorflow\u5df2\u7ecf\u7981\u6b62\u5728\u5355\u8f93\u51fa\u7684\u65f6\u5019\u4f7f\u7528CE\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u8fd9\u7bc7\u6587\u7ae0\u8ba8\u8bbabinary_crossentropy\u3001(sparse)categorical_cros 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