{"version":2,"relationshipURLBase":"https://codingai-lec03.pages.dev/course/notebooks/23b0affc4b824723927bd0938fd2bbda.html","relationshipResolution":"Resolve relative relationship URLs against relationshipURLBase; complete records and absolute URLs are in blocks.","title":"CLS 04 · 重建：约束、位置与表示评价","url":"https://codingai-lec03.pages.dev/course/notebooks/23b0affc4b824723927bd0938fd2bbda.html","markdown":"https://codingai-lec03.pages.dev/course/notebooks/23b0affc4b824723927bd0938fd2bbda.md","pages":[{"id":"reading-opening","title":"CLS 04 · 重建：约束、位置与表示评价","unit":"训练留下什么，训练答案又从哪里来？","unitId":"i-reuse-and-targets","chapter":"I","number":1},{"id":"reading-block-a06579c00c0d4cf0a190f71ae8b83559","title":"同样是压缩，离散词典与线性子空间留下不同东西","unit":"训练留下什么，训练答案又从哪里来？","unitId":"i-reuse-and-targets","chapter":"I","number":2},{"id":"reading-block-5dc1a98878994b8989105349ef7bd0c6","title":"MAE 让昂贵编码器只看少量位置","unit":"训练留下什么，训练答案又从哪里来？","unitId":"i-reuse-and-targets","chapter":"I","number":3},{"id":"reading-block-de414705e5654ffa86fc46358756877d","title":"读到这里，可以如何继续？","unit":"训练留下什么，训练答案又从哪里来？","unitId":"i-reuse-and-targets","chapter":"I","number":4}],"aliases":[{"oldId":"b-3312d5e0f3ef13d4cf18f410","targetId":"b-3312d5e0f3ef13d4cf18f410","page":"reading-opening","operation":"move","beforeSHA256":"4b32e93b37622319bc268dfcb993d4399abc4ee7dffabf03be88fa420b57d5d0","afterSHA256":"4b32e93b37622319bc268dfcb993d4399abc4ee7dffabf03be88fa420b57d5d0","reason":"Same source body in authored semantic page"},{"oldId":"b-fd1d71324e42aa37e84d6988","targetId":"b-fd1d71324e42aa37e84d6988","page":"reading-opening","operation":"move","beforeSHA256":"e91f24e4e4ca40e2099a0d81d30db6568f4bf2074b499eeee6e3959617bd97ac","afterSHA256":"e91f24e4e4ca40e2099a0d81d30db6568f4bf2074b499eeee6e3959617bd97ac","reason":"Same source body in authored semantic page"},{"oldId":"b-5c4aad36e75b15eeb5ed26c8","targetId":"b-5c4aad36e75b15eeb5ed26c8","page":"reading-opening","operation":"move","beforeSHA256":"db36e128a2d5a5e8c2d5360cbf60671bab45cb5494bbdd81f27d6b7d95ea74e0","afterSHA256":"db36e128a2d5a5e8c2d5360cbf60671bab45cb5494bbdd81f27d6b7d95ea74e0","reason":"Same source body in authored semantic page"},{"oldId":"b-a85255145548ce6d796739bd","targetId":"b-a85255145548ce6d796739bd","page":"reading-opening","operation":"move","beforeSHA256":"f22152fd55dcdb0090b5653d37145694fd19388d31e10226549464fe8b483578","afterSHA256":"f22152fd55dcdb0090b5653d37145694fd19388d31e10226549464fe8b483578","reason":"Same source body in authored semantic page"},{"oldId":"b-d659ac0c8e61f9e801ef51ad","targetId":"b-d659ac0c8e61f9e801ef51ad","page":"reading-block-a06579c00c0d4cf0a190f71ae8b83559","operation":"move","beforeSHA256":"8556351a0a818e5fa2ef8199862458dc0e7165abe7355c0f371bb6d655e593e9","afterSHA256":"8556351a0a818e5fa2ef8199862458dc0e7165abe7355c0f371bb6d655e593e9","reason":"Same source body in authored semantic page"},{"oldId":"b-e0914c449f173bf286302127","targetId":"b-e0914c449f173bf286302127","page":"reading-block-a06579c00c0d4cf0a190f71ae8b83559","operation":"move","beforeSHA256":"33a9d35da9bf638cbbb8b5e9354a73f8d26efaaa61832a0a1a404bed3367025a","afterSHA256":"33a9d35da9bf638cbbb8b5e9354a73f8d26efaaa61832a0a1a404bed3367025a","reason":"Same source body in authored semantic page"},{"oldId":"b-19f1778a40e32f52e222af9b","targetId":"b-19f1778a40e32f52e222af9b","page":"reading-block-a06579c00c0d4cf0a190f71ae8b83559","operation":"move","beforeSHA256":"2864bf0006511ecd508b2de87e5c323f9679695de8967deee935355762a68f4c","afterSHA256":"2864bf0006511ecd508b2de87e5c323f9679695de8967deee935355762a68f4c","reason":"Same source body in authored semantic page"},{"oldId":"b-79826c68fcfe11a0afc4a89f","targetId":"b-79826c68fcfe11a0afc4a89f","page":"reading-block-a06579c00c0d4cf0a190f71ae8b83559","operation":"move","beforeSHA256":"9e07fc295fe95877d90b697ad5fa48296f312a7ab8d0889774a5f486fd8d090d","afterSHA256":"9e07fc295fe95877d90b697ad5fa48296f312a7ab8d0889774a5f486fd8d090d","reason":"Same source body in authored semantic page"},{"oldId":"b-4e1c304d77b43e2cc6873f9d","targetId":"b-4e1c304d77b43e2cc6873f9d","page":"reading-block-a06579c00c0d4cf0a190f71ae8b83559","operation":"move","beforeSHA256":"a8be541fcaf19bfce2bf41f6779590be20eb214a5f4faf49be22dcf9a7d9bbc0","afterSHA256":"a8be541fcaf19bfce2bf41f6779590be20eb214a5f4faf49be22dcf9a7d9bbc0","reason":"Same source body in authored semantic page"},{"oldId":"b-33afa96feecd635216bf5bc3","targetId":"b-33afa96feecd635216bf5bc3","page":"reading-block-a06579c00c0d4cf0a190f71ae8b83559","operation":"move","beforeSHA256":"9a8088a16b7096a914d6ede16623634ce17a57528701ccdb6e9cb90e6d1c8e7f","afterSHA256":"9a8088a16b7096a914d6ede16623634ce17a57528701ccdb6e9cb90e6d1c8e7f","reason":"Same source body in authored semantic page"},{"oldId":"b-db878571043a5015e7f376b4","targetId":"b-db878571043a5015e7f376b4","page":"reading-block-a06579c00c0d4cf0a190f71ae8b83559","operation":"move","beforeSHA256":"ab7a10e9728afbecdcec79d3f12505658449566b8277e7632a8f41cdc23677f7","afterSHA256":"ab7a10e9728afbecdcec79d3f12505658449566b8277e7632a8f41cdc23677f7","reason":"Same source body in authored semantic page"},{"oldId":"b-01b418c56d7218bd232f55fa","targetId":"b-01b418c56d7218bd232f55fa","page":"reading-block-a06579c00c0d4cf0a190f71ae8b83559","operation":"move","beforeSHA256":"aef13a0897067ed8c716ad7ba8fabf84019f69a5ea2017415804af017d79c7b6","afterSHA256":"aef13a0897067ed8c716ad7ba8fabf84019f69a5ea2017415804af017d79c7b6","reason":"Same source body in authored semantic page"},{"oldId":"b-71464123c6b8a2cd777715b1","targetId":"b-71464123c6b8a2cd777715b1","page":"reading-block-a06579c00c0d4cf0a190f71ae8b83559","operation":"move","beforeSHA256":"b95322b58e86aab97b9239ea97f9fbcd76a279b78c510fe88e115594dd0cd9ea","afterSHA256":"b95322b58e86aab97b9239ea97f9fbcd76a279b78c510fe88e115594dd0cd9ea","reason":"Same source body in authored semantic page"},{"oldId":"b-e4bfbed8e165c603adb793c3","targetId":"b-e4bfbed8e165c603adb793c3","page":"reading-block-a06579c00c0d4cf0a190f71ae8b83559","operation":"move","beforeSHA256":"314d138cb51e798d2754f0d3a4ea9e9f5db2ea2051da32427b62b50db0088186","afterSHA256":"314d138cb51e798d2754f0d3a4ea9e9f5db2ea2051da32427b62b50db0088186","reason":"Same source body in authored semantic page"},{"oldId":"b-ca2fccb4caf5553bf1346a7e","targetId":"b-ca2fccb4caf5553bf1346a7e","page":"reading-block-a06579c00c0d4cf0a190f71ae8b83559","operation":"move","beforeSHA256":"da8a5c96a3492ad378af6c0cbf696fd54ccd53c2c29bbc8e794d30c3a07e225e","afterSHA256":"da8a5c96a3492ad378af6c0cbf696fd54ccd53c2c29bbc8e794d30c3a07e225e","reason":"Same source body in authored semantic page"},{"oldId":"b-675220a8dbd5367e51ed3124","targetId":"b-675220a8dbd5367e51ed3124","page":"reading-block-a06579c00c0d4cf0a190f71ae8b83559","operation":"move","beforeSHA256":"5e93b74f70085ca5ec3b76b71d57b2a105f5a18720df2082b57f0ac8f1df1499","afterSHA256":"5e93b74f70085ca5ec3b76b71d57b2a105f5a18720df2082b57f0ac8f1df1499","reason":"Same source body in authored semantic page"},{"oldId":"b-ca77a8e58c99015f1fa412f0","targetId":"b-ca77a8e58c99015f1fa412f0","page":"reading-block-a06579c00c0d4cf0a190f71ae8b83559","operation":"move","beforeSHA256":"7ed392f7e5f8093e27fad86ce7c3c1dd94875138594c09c1db623b85a4946a51","afterSHA256":"7ed392f7e5f8093e27fad86ce7c3c1dd94875138594c09c1db623b85a4946a51","reason":"Same source body in authored semantic page"},{"oldId":"b-24327531b5d13c8b3e6df4d7","targetId":"b-24327531b5d13c8b3e6df4d7","page":"reading-block-a06579c00c0d4cf0a190f71ae8b83559","operation":"move","beforeSHA256":"859cfeee5fb3ba73e84cd3892eaf1ea08e08ffef5ebf530789c7027945093b85","afterSHA256":"859cfeee5fb3ba73e84cd3892eaf1ea08e08ffef5ebf530789c7027945093b85","reason":"Same source body in authored semantic page"},{"oldId":"b-0e6824050e5ad32f33efd9f3","targetId":"b-0e6824050e5ad32f33efd9f3","page":"reading-block-a06579c00c0d4cf0a190f71ae8b83559","operation":"move","beforeSHA256":"1ec743964fe5a8b6a41542c2f230348bcf69b21f317b8a22ea2f1483ada27a4b","afterSHA256":"1ec743964fe5a8b6a41542c2f230348bcf69b21f317b8a22ea2f1483ada27a4b","reason":"Same source body in authored semantic page"},{"oldId":"b-93b2489c1128c96e28fe67bb","targetId":"b-93b2489c1128c96e28fe67bb","page":"reading-block-a06579c00c0d4cf0a190f71ae8b83559","operation":"move","beforeSHA256":"e62fcdbdf8f5d621235c6d665a17152c1736f9eb0ff056daa0c2d302d56ee703","afterSHA256":"e62fcdbdf8f5d621235c6d665a17152c1736f9eb0ff056daa0c2d302d56ee703","reason":"Same source body in authored semantic page"},{"oldId":"b-1c4cdab0cdd9cb61ad129365","targetId":"b-1c4cdab0cdd9cb61ad129365","page":"reading-block-a06579c00c0d4cf0a190f71ae8b83559","operation":"move","beforeSHA256":"4d82f52f7518bc4d90a45a49b8188143486de499bd9a390f4e9be7d7b2985f15","afterSHA256":"4d82f52f7518bc4d90a45a49b8188143486de499bd9a390f4e9be7d7b2985f15","reason":"Same source body in authored semantic page"},{"oldId":"b-467542c59d5a59f673502bb2","targetId":"b-467542c59d5a59f673502bb2","page":"reading-block-a06579c00c0d4cf0a190f71ae8b83559","operation":"move","beforeSHA256":"54a1680c2cde89592947009c399bb9696954ae9ee53a7738e72503f17248e65a","afterSHA256":"54a1680c2cde89592947009c399bb9696954ae9ee53a7738e72503f17248e65a","reason":"Same source body in authored semantic page"},{"oldId":"b-6495b73464e7c0ae118a26c1","targetId":"b-6495b73464e7c0ae118a26c1","page":"reading-block-5dc1a98878994b8989105349ef7bd0c6","operation":"move","beforeSHA256":"94c92248638a95e30f63c78bc247c7bac3e334d71bda920fd01554a003dbda6d","afterSHA256":"94c92248638a95e30f63c78bc247c7bac3e334d71bda920fd01554a003dbda6d","reason":"Same source body in authored semantic page"},{"oldId":"b-ea05ca62677bd60a465ad3da","targetId":"b-ea05ca62677bd60a465ad3da","page":"reading-block-5dc1a98878994b8989105349ef7bd0c6","operation":"move","beforeSHA256":"11689a6e9d1b70e1f58e6c9dc369e5b3e87fa0cb70c4c6f28d85cbea174eb60a","afterSHA256":"11689a6e9d1b70e1f58e6c9dc369e5b3e87fa0cb70c4c6f28d85cbea174eb60a","reason":"Same source body in authored semantic page"},{"oldId":"b-81f16299a07a6a4f230ef6fe","targetId":"b-81f16299a07a6a4f230ef6fe","page":"reading-block-5dc1a98878994b8989105349ef7bd0c6","operation":"move","beforeSHA256":"5ac484a3f720ac4cf71140e2cb746a9e171f2c492b27c78bb5e433c48f6370f7","afterSHA256":"5ac484a3f720ac4cf71140e2cb746a9e171f2c492b27c78bb5e433c48f6370f7","reason":"Same source body in authored semantic page"},{"oldId":"b-7c4520c091ca095437cbb5e2","targetId":"b-7c4520c091ca095437cbb5e2","page":"reading-block-5dc1a98878994b8989105349ef7bd0c6","operation":"move","beforeSHA256":"b5e0f378794cb8b5e98506bac2baa689d3b4fed7d73ae9b28175dfaaf27dbe4b","afterSHA256":"b5e0f378794cb8b5e98506bac2baa689d3b4fed7d73ae9b28175dfaaf27dbe4b","reason":"Same source body in authored semantic page"},{"oldId":"b-ad427a7490382a36cd37152b","targetId":"b-ad427a7490382a36cd37152b","page":"reading-block-5dc1a98878994b8989105349ef7bd0c6","operation":"move","beforeSHA256":"3f5dc0bbd2e7534e9bd07a1f682b523e93864d9abfc9188f92d5dc37ff605a01","afterSHA256":"3f5dc0bbd2e7534e9bd07a1f682b523e93864d9abfc9188f92d5dc37ff605a01","reason":"Same source body in authored semantic page"},{"oldId":"b-7ecbfffadd7dbcaaa97d4d36","targetId":"b-7ecbfffadd7dbcaaa97d4d36","page":"reading-block-5dc1a98878994b8989105349ef7bd0c6","operation":"move","beforeSHA256":"36259a44332912c3afa0a6cc99679f3f32046cdd68b393af2a095cb0dc8b8542","afterSHA256":"36259a44332912c3afa0a6cc99679f3f32046cdd68b393af2a095cb0dc8b8542","reason":"Same source body in authored semantic page"},{"oldId":"b-f50bbfaeb5e096335e8c6ca8","targetId":"b-f50bbfaeb5e096335e8c6ca8","page":"reading-block-5dc1a98878994b8989105349ef7bd0c6","operation":"rewrite","beforeSHA256":"c0823b50d032b609150e0475d34c6006c1e48c8a07e376dcdbee74ebc8409eb8","afterSHA256":"762a8c5fbf71524b89e155ad28cc9e70823159c29af9b3f81e9709b17aef7982","reason":"Same source identity with figure semantics or reading context enriched"},{"oldId":"b-0d3b2cd8f51753409fd465e1","targetId":"b-0d3b2cd8f51753409fd465e1","page":"reading-block-5dc1a98878994b8989105349ef7bd0c6","operation":"move","beforeSHA256":"bdd741431b0bfcf6895a3ec1e163d576a9a39b43e2d32f28568c43e170bf94d1","afterSHA256":"bdd741431b0bfcf6895a3ec1e163d576a9a39b43e2d32f28568c43e170bf94d1","reason":"Same source body in authored semantic page"},{"oldId":"b-0c3f4f1d4bf60563ac95dd53","targetId":"b-0c3f4f1d4bf60563ac95dd53","page":"reading-block-5dc1a98878994b8989105349ef7bd0c6","operation":"move","beforeSHA256":"63ef714a664c8436ef49a563821c2fb3836648b0e9361da95f69018103d353e6","afterSHA256":"63ef714a664c8436ef49a563821c2fb3836648b0e9361da95f69018103d353e6","reason":"Same source body in authored semantic page"},{"oldId":"b-34a5a91394ac8cf3909a99a7","targetId":"b-34a5a91394ac8cf3909a99a7","page":"reading-block-5dc1a98878994b8989105349ef7bd0c6","operation":"move","beforeSHA256":"ba893ef885b664c6949f9713db226dd1b41af3d792fd9ab9f3d46cee131de26b","afterSHA256":"ba893ef885b664c6949f9713db226dd1b41af3d792fd9ab9f3d46cee131de26b","reason":"Same source body in authored semantic page"},{"oldId":"b-2c227cbeea64ba8666f0cce5","targetId":"b-2c227cbeea64ba8666f0cce5","page":"reading-block-5dc1a98878994b8989105349ef7bd0c6","operation":"rewrite","beforeSHA256":"3a586279318b165191ce70d3d763f8cfaa1fde74125422ac404a69584f33b5e0","afterSHA256":"abc9ce8051bfb0d16d084f87dc7c4be7312f5993868cfd50a3846998ba18fc0c","reason":"Same source identity with figure semantics or reading context enriched"},{"oldId":"b-9c355486e6684f56953b0389","targetId":"b-9c355486e6684f56953b0389","page":"reading-block-5dc1a98878994b8989105349ef7bd0c6","operation":"move","beforeSHA256":"686b884b78320da1fd4e9f3041bd3fe80f96edebbbe915a529890ae251d76293","afterSHA256":"122ba20c7f0fe242e9c627f9ff6ce34ff9163bdabed0dd9bdccd57346b14e7aa","reason":"Same source body in authored semantic page"},{"oldId":"b-8a381b9380cb92a11f46a093","targetId":"b-8a381b9380cb92a11f46a093","page":"reading-block-5dc1a98878994b8989105349ef7bd0c6","operation":"move","beforeSHA256":"6d6419fd9b8cf38b3215e50deaae56b50c8735f4332672de31f0b542104500bf","afterSHA256":"6d6419fd9b8cf38b3215e50deaae56b50c8735f4332672de31f0b542104500bf","reason":"Same source body in authored semantic page"},{"oldId":"b-bbfa19c6378704b6ed179dc8","targetId":"b-bbfa19c6378704b6ed179dc8","page":"reading-block-5dc1a98878994b8989105349ef7bd0c6","operation":"move","beforeSHA256":"3299792b5c910a1b3a63b2c4677082dda6868df4222b47dc500d9c26add22fe1","afterSHA256":"3299792b5c910a1b3a63b2c4677082dda6868df4222b47dc500d9c26add22fe1","reason":"Same source body in authored semantic page"},{"oldId":"b-a670e67f7a7d90be0b69730d","targetId":"b-a670e67f7a7d90be0b69730d","page":"reading-block-5dc1a98878994b8989105349ef7bd0c6","operation":"move","beforeSHA256":"342160d8a63afceb0d11b164fdae9c202f3e9be639da6a98adb895229b074ebe","afterSHA256":"342160d8a63afceb0d11b164fdae9c202f3e9be639da6a98adb895229b074ebe","reason":"Same source body in authored semantic page"},{"oldId":"b-3a992f97494e539edfcef62a","targetId":"b-3a992f97494e539edfcef62a","page":"reading-block-de414705e5654ffa86fc46358756877d","operation":"move","beforeSHA256":"04be615138958c4f13e412819a718d3f4afc47be02d77e4b8871d61299bcc9ac","afterSHA256":"04be615138958c4f13e412819a718d3f4afc47be02d77e4b8871d61299bcc9ac","reason":"Same source body in authored semantic page"},{"oldId":"b-260d8aaf32019c7f477bcb6b","targetId":"b-260d8aaf32019c7f477bcb6b","page":"reading-block-de414705e5654ffa86fc46358756877d","operation":"move","beforeSHA256":"0780b00bec94dbc4e96f95a3bf9900917f0d6e14d81049bff765713475e3bb8a","afterSHA256":"0780b00bec94dbc4e96f95a3bf9900917f0d6e14d81049bff765713475e3bb8a","reason":"Same source body in authored semantic page"},{"oldId":"b-0365516971f31a96dbdeacb5","targetId":"b-0365516971f31a96dbdeacb5","page":"reading-block-de414705e5654ffa86fc46358756877d","operation":"move","beforeSHA256":"bc4055cdc99830b8f219631da25dae26736fa6c22ea57660169ddb5b6ac76cde","afterSHA256":"bc4055cdc99830b8f219631da25dae26736fa6c22ea57660169ddb5b6ac76cde","reason":"Same source body in authored semantic 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08](https://deepnote.com/project/38755e4e-23f6-4f5f-8c68-8a2e4114b1c1/notebook/b5ba27f2c5ba4ec0922208a7d5dc80a4)保存的同图重建与冻结读出。你的产出是一张对照：模型恢复了哪些像素，哪些下游能力另外测过，两者为什么不能互相代替。","sha256":"2864bf0006511ecd508b2de87e5c323f9679695de8967deee935355762a68f4c","chapter":{"id":"I","title":"学习信号与表示"},"unit":{"id":"i-reuse-and-targets","title":"训练留下什么，训练答案又从哪里来？"},"page":{"id":"reading-block-a06579c00c0d4cf0a190f71ae8b83559","title":"同样是压缩，离散词典与线性子空间留下不同东西","number":2},"sectionTitle":"同样是压缩，离散词典与线性子空间留下不同东西","currentQuestion":"同样是压缩，离散词典与线性子空间留下不同东西","sourceSlides":[],"knowledgeBlock":null,"formulas":[],"previousBlock":"b-e0914c449f173bf286302127","nextBlock":"b-79826c68fcfe11a0afc4a89f","prerequisites":[{"id":"b-d659ac0c8e61f9e801ef51ad","url":"#b-d659ac0c8e61f9e801ef51ad","role":"problem-context"}],"relatedBlocks":[]},{"id":"b-79826c68fcfe11a0afc4a89f","type":"p","scope":"block-a06579c00c0d4cf0a190f71ae8b83559","url":"https://codingai-lec03.pages.dev/course/notebooks/23b0affc4b824723927bd0938fd2bbda.html#b-79826c68fcfe11a0afc4a89f","content":"PCA、去噪与词典的推导保留在前半部，遇到瓶颈或误差问题再回读。需要一个无需神经网络的实际优化入口时，选[LAB 05像素词典](https://deepnote.com/project/38755e4e-23f6-4f5f-8c68-8a2e4114b1c1/notebook/de39b998077f44cca4b8407085547766)。可直接引用[隐藏loss分母](/course/blocks/mae-masked-loss-denominator.html)或[重建限制](/course/blocks/reconstruction-restrictions.html)。","sha256":"9e07fc295fe95877d90b697ad5fa48296f312a7ab8d0889774a5f486fd8d090d","chapter":{"id":"I","title":"学习信号与表示"},"unit":{"id":"i-reuse-and-targets","title":"训练留下什么，训练答案又从哪里来？"},"page":{"id":"reading-block-a06579c00c0d4cf0a190f71ae8b83559","title":"同样是压缩，离散词典与线性子空间留下不同东西","number":2},"sectionTitle":"同样是压缩，离散词典与线性子空间留下不同东西","currentQuestion":"同样是压缩，离散词典与线性子空间留下不同东西","sourceSlides":[],"knowledgeBlock":null,"formulas":[],"previousBlock":"b-19f1778a40e32f52e222af9b","nextBlock":"b-4e1c304d77b43e2cc6873f9d","prerequisites":[{"id":"b-d659ac0c8e61f9e801ef51ad","url":"#b-d659ac0c8e61f9e801ef51ad","role":"problem-context"}],"relatedBlocks":[]},{"id":"b-4e1c304d77b43e2cc6873f9d","type":"p","scope":"block-a06579c00c0d4cf0a190f71ae8b83559","url":"https://codingai-lec03.pages.dev/course/notebooks/23b0affc4b824723927bd0938fd2bbda.html#b-4e1c304d77b43e2cc6873f9d","content":"如果不提供“猫”“杯子”这样的类别标签，图像还有什么可以当答案？最直接的是图像自身：把它压缩、破坏或遮住一部分，再让模型恢复。困难不在于是否有监督数值，而在于我们允许模型怎样取得它。把输入原样复制到输出可以获得零误差，却没有迫使模型形成有用的表示。重建方法之间真正改变的是限制条件：代码可以取什么值、信息从哪里通过、哪些位置可见，以及误差计算在哪里。","sha256":"a8be541fcaf19bfce2bf41f6779590be20eb214a5f4faf49be22dcf9a7d9bbc0","chapter":{"id":"I","title":"学习信号与表示"},"unit":{"id":"i-reuse-and-targets","title":"训练留下什么，训练答案又从哪里来？"},"page":{"id":"reading-block-a06579c00c0d4cf0a190f71ae8b83559","title":"同样是压缩，离散词典与线性子空间留下不同东西","number":2},"sectionTitle":"同样是压缩，离散词典与线性子空间留下不同东西","currentQuestion":"同样是压缩，离散词典与线性子空间留下不同东西","sourceSlides":[],"knowledgeBlock":null,"formulas":[],"previousBlock":"b-79826c68fcfe11a0afc4a89f","nextBlock":"b-33afa96feecd635216bf5bc3","prerequisites":[{"id":"b-d659ac0c8e61f9e801ef51ad","url":"#b-d659ac0c8e61f9e801ef51ad","role":"problem-context"}],"relatedBlocks":[]},{"id":"b-33afa96feecd635216bf5bc3","type":"h2","scope":"block-a06579c00c0d4cf0a190f71ae8b83559","url":"https://codingai-lec03.pages.dev/course/notebooks/23b0affc4b824723927bd0938fd2bbda.html#b-33afa96feecd635216bf5bc3","content":"## 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05](https://deepnote.com/workspace/ise3309jingao-5ba66b0a-4283-4f5a-ae06-3f68d3201e99/project/38755e4e-23f6-4f5f-8c68-8a2e4114b1c1/notebook/de39b998077f44cca4b8407085547766?utm_source=openai&utm_medium=mcp&utm_campaign=openaimcp&utm_content=de39b998077f44cca4b8407085547766&utm_term=get_notebook) 在真实 MNIST patch 上进行 Lloyd 拟合，可查看中心怎样随数据形成，而非只背“无监督”这个标签。","sha256":"b95322b58e86aab97b9239ea97f9fbcd76a279b78c510fe88e115594dd0cd9ea","chapter":{"id":"I","title":"学习信号与表示"},"unit":{"id":"i-reuse-and-targets","title":"训练留下什么，训练答案又从哪里来？"},"page":{"id":"reading-block-a06579c00c0d4cf0a190f71ae8b83559","title":"同样是压缩，离散词典与线性子空间留下不同东西","number":2},"sectionTitle":"同样是压缩，离散词典与线性子空间留下不同东西","currentQuestion":"同样是压缩，离散词典与线性子空间留下不同东西","sourceSlides":[],"knowledgeBlock":null,"formulas":[{"latex":"c_1=(1,0,1,0)","definitionContext":"同样是压缩，离散词典与线性子空间留下不同东西"},{"latex":"c_2=(0,1,0,1)","definitionContext":"同样是压缩，离散词典与线性子空间留下不同东西"},{"latex":"(0.5,0.5,0.5,0.5)","definitionContext":"同样是压缩，离散词典与线性子空间留下不同东西"},{"latex":"\\log_2 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的平方误差与 MAE 的位置恢复](/course/repair/assets/cls05-pca-mask.svg)","sha256":"5e93b74f70085ca5ec3b76b71d57b2a105f5a18720df2082b57f0ac8f1df1499","chapter":{"id":"I","title":"学习信号与表示"},"unit":{"id":"i-reuse-and-targets","title":"训练留下什么，训练答案又从哪里来？"},"page":{"id":"reading-block-a06579c00c0d4cf0a190f71ae8b83559","title":"同样是压缩，离散词典与线性子空间留下不同东西","number":2},"sectionTitle":"同样是压缩，离散词典与线性子空间留下不同东西","currentQuestion":"同样是压缩，离散词典与线性子空间留下不同东西","sourceSlides":[],"knowledgeBlock":null,"formulas":[],"previousBlock":"b-ca2fccb4caf5553bf1346a7e","nextBlock":"b-ca77a8e58c99015f1fa412f0","prerequisites":[{"id":"b-33afa96feecd635216bf5bc3","url":"#b-33afa96feecd635216bf5bc3","role":"section-title"},{"id":"b-d659ac0c8e61f9e801ef51ad","url":"#b-d659ac0c8e61f9e801ef51ad","role":"problem-context"}],"relatedBlocks":[]},{"id":"b-ca77a8e58c99015f1fa412f0","type":"p","scope":"block-a06579c00c0d4cf0a190f71ae8b83559","url":"https://codingai-lec03.pages.dev/course/notebooks/23b0affc4b824723927bd0938fd2bbda.html#b-ca77a8e58c99015f1fa412f0","content":"左图按真实坐标画出四点和一维投影；右图展示 patch 的乱序、可见项与恢复位置。两者都在重建，但一个限制子空间，一个限制输入可见性。","sha256":"7ed392f7e5f8093e27fad86ce7c3c1dd94875138594c09c1db623b85a4946a51","chapter":{"id":"I","title":"学习信号与表示"},"unit":{"id":"i-reuse-and-targets","title":"训练留下什么，训练答案又从哪里来？"},"page":{"id":"reading-block-a06579c00c0d4cf0a190f71ae8b83559","title":"同样是压缩，离散词典与线性子空间留下不同东西","number":2},"sectionTitle":"同样是压缩，离散词典与线性子空间留下不同东西","currentQuestion":"同样是压缩，离散词典与线性子空间留下不同东西","sourceSlides":[],"knowledgeBlock":null,"formulas":[],"previousBlock":"b-675220a8dbd5367e51ed3124","nextBlock":"b-24327531b5d13c8b3e6df4d7","prerequisites":[{"id":"b-33afa96feecd635216bf5bc3","url":"#b-33afa96feecd635216bf5bc3","role":"section-title"},{"id":"b-d659ac0c8e61f9e801ef51ad","url":"#b-d659ac0c8e61f9e801ef51ad","role":"problem-context"}],"relatedBlocks":[]},{"id":"b-24327531b5d13c8b3e6df4d7","type":"h2","scope":"block-a06579c00c0d4cf0a190f71ae8b83559","url":"https://codingai-lec03.pages.dev/course/notebooks/23b0affc4b824723927bd0938fd2bbda.html#b-24327531b5d13c8b3e6df4d7","content":"## PCA 为什么可以看成受约束的线性自编码器","sha256":"859cfeee5fb3ba73e84cd3892eaf1ea08e08ffef5ebf530789c7027945093b85","chapter":{"id":"I","title":"学习信号与表示"},"unit":{"id":"i-reuse-and-targets","title":"训练留下什么，训练答案又从哪里来？"},"page":{"id":"reading-block-a06579c00c0d4cf0a190f71ae8b83559","title":"同样是压缩，离散词典与线性子空间留下不同东西","number":2},"sectionTitle":"同样是压缩，离散词典与线性子空间留下不同东西","currentQuestion":"同样是压缩，离散词典与线性子空间留下不同东西","sourceSlides":[],"knowledgeBlock":null,"formulas":[],"previousBlock":"b-ca77a8e58c99015f1fa412f0","nextBlock":"b-0e6824050e5ad32f33efd9f3","prerequisites":[{"id":"b-33afa96feecd635216bf5bc3","url":"#b-33afa96feecd635216bf5bc3","role":"section-title"},{"id":"b-d659ac0c8e61f9e801ef51ad","url":"#b-d659ac0c8e61f9e801ef51ad","role":"problem-context"}],"relatedBlocks":[]},{"id":"b-0e6824050e5ad32f33efd9f3","type":"p","scope":"block-a06579c00c0d4cf0a190f71ae8b83559","url":"https://codingai-lec03.pages.dev/course/notebooks/23b0affc4b824723927bd0938fd2bbda.html#b-0e6824050e5ad32f33efd9f3","content":"自编码器由 $z=f_\\theta(x)$ 与 $\\hat x=g_\\phi(z)$ 组成，以 $\\|x-\\hat x\\|^2$ 等重建损失更新参数。令 $f(x)=U^Tx,g(z)=Uz$ 并要求 $U^TU=I$，就得到上面的 PCA 形式。一般线性、低秩、平方误差自编码器也能学到 PCA 的主子空间，尽管编码坐标不一定等于标准主成分；平移、旋转等参数化差异要与重建子空间区分。","sha256":"1ec743964fe5a8b6a41542c2f230348bcf69b21f317b8a22ea2f1483ada27a4b","chapter":{"id":"I","title":"学习信号与表示"},"unit":{"id":"i-reuse-and-targets","title":"训练留下什么，训练答案又从哪里来？"},"page":{"id":"reading-block-a06579c00c0d4cf0a190f71ae8b83559","title":"同样是压缩，离散词典与线性子空间留下不同东西","number":2},"sectionTitle":"同样是压缩，离散词典与线性子空间留下不同东西","currentQuestion":"同样是压缩，离散词典与线性子空间留下不同东西","sourceSlides":[],"knowledgeBlock":null,"formulas":[{"latex":"z=f_\\theta(x)","definitionContext":"同样是压缩，离散词典与线性子空间留下不同东西"},{"latex":"\\hat x=g_\\phi(z)","definitionContext":"同样是压缩，离散词典与线性子空间留下不同东西"},{"latex":"\\|x-\\hat 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$\\tilde x\\sim q(\\tilde x\\mid x)$，再最小化 $\\mathbb E\\|g(f(\\tilde x))-x\\|^2$。输入是带噪图片，目标仍是干净图片。训练时不给模型干净图，不能在可视化时偷偷把目标的边缘或 mask 喂回去。Gaussian 噪声、置零像素和随机遮块提出不同恢复任务；噪声太轻会接近复制，太重可能留下不足以判断的证据。在 [去噪自编码器原论文](https://www.jmlr.org/papers/v11/vincent10a.html) 中，破坏过程正是组织表示学习的一个关键约束。","sha256":"4d82f52f7518bc4d90a45a49b8188143486de499bd9a390f4e9be7d7b2985f15","chapter":{"id":"I","title":"学习信号与表示"},"unit":{"id":"i-reuse-and-targets","title":"训练留下什么，训练答案又从哪里来？"},"page":{"id":"reading-block-a06579c00c0d4cf0a190f71ae8b83559","title":"同样是压缩，离散词典与线性子空间留下不同东西","number":2},"sectionTitle":"同样是压缩，离散词典与线性子空间留下不同东西","currentQuestion":"同样是压缩，离散词典与线性子空间留下不同东西","sourceSlides":[],"knowledgeBlock":null,"formulas":[{"latex":"\\tilde x\\sim q(\\tilde x\\mid x)","definitionContext":"同样是压缩，离散词典与线性子空间留下不同东西"},{"latex":"\\mathbb E\\|g(f(\\tilde 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MAE 让昂贵编码器只看少量位置","sha256":"94c92248638a95e30f63c78bc247c7bac3e334d71bda920fd01554a003dbda6d","chapter":{"id":"I","title":"学习信号与表示"},"unit":{"id":"i-reuse-and-targets","title":"训练留下什么，训练答案又从哪里来？"},"page":{"id":"reading-block-5dc1a98878994b8989105349ef7bd0c6","title":"MAE 让昂贵编码器只看少量位置","number":3},"sectionTitle":"MAE 让昂贵编码器只看少量位置","currentQuestion":"MAE 让昂贵编码器只看少量位置","sourceSlides":[],"knowledgeBlock":null,"formulas":[],"previousBlock":null,"nextBlock":"b-ea05ca62677bd60a465ad3da","prerequisites":[{"id":"b-ea05ca62677bd60a465ad3da","url":"#b-ea05ca62677bd60a465ad3da","role":"problem-context"}],"relatedBlocks":[]},{"id":"b-ea05ca62677bd60a465ad3da","type":"p","scope":"block-5dc1a98878994b8989105349ef7bd0c6","url":"https://codingai-lec03.pages.dev/course/notebooks/23b0affc4b824723927bd0938fd2bbda.html#b-ea05ca62677bd60a465ad3da","content":"把图像切为 patch 后，MAE 随机选择可见子集，编码器只处理可见 patch 及其位置；轻量解码器补入 mask token，恢复完整位置顺序，再预测被遮挡的像素目标。原 MAE 的一个关键设计是高遮挡率与这种不对称编码—解码结构，见 [MAE §3 与图 1](https://arxiv.org/html/2111.06377v3)。这里不是先让编码器看完整图，再在输出端涂黑几块。","sha256":"11689a6e9d1b70e1f58e6c9dc369e5b3e87fa0cb70c4c6f28d85cbea174eb60a","chapter":{"id":"I","title":"学习信号与表示"},"unit":{"id":"i-reuse-and-targets","title":"训练留下什么，训练答案又从哪里来？"},"page":{"id":"reading-block-5dc1a98878994b8989105349ef7bd0c6","title":"MAE 让昂贵编码器只看少量位置","number":3},"sectionTitle":"MAE 让昂贵编码器只看少量位置","currentQuestion":"MAE 让昂贵编码器只看少量位置","sourceSlides":[],"knowledgeBlock":null,"formulas":[],"previousBlock":"b-6495b73464e7c0ae118a26c1","nextBlock":"b-81f16299a07a6a4f230ef6fe","prerequisites":[{"id":"b-6495b73464e7c0ae118a26c1","url":"#b-6495b73464e7c0ae118a26c1","role":"section-title"}],"relatedBlocks":[]},{"id":"b-81f16299a07a6a4f230ef6fe","type":"p","scope":"block-5dc1a98878994b8989105349ef7bd0c6","url":"https://codingai-lec03.pages.dev/course/notebooks/23b0affc4b824723927bd0938fd2bbda.html#b-81f16299a07a6a4f230ef6fe","content":"四个原始位置是 `[0,1,2,3]`。随机排列 `ids_shuffle=[2,0,3,1]`，只保留前两项，所以编码器看到原位置 2、0。解码器先得到 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让昂贵编码器只看少量位置","sourceSlides":[],"knowledgeBlock":null,"formulas":[],"previousBlock":"b-ea05ca62677bd60a465ad3da","nextBlock":"b-7c4520c091ca095437cbb5e2","prerequisites":[{"id":"b-6495b73464e7c0ae118a26c1","url":"#b-6495b73464e7c0ae118a26c1","role":"section-title"},{"id":"b-ea05ca62677bd60a465ad3da","url":"#b-ea05ca62677bd60a465ad3da","role":"problem-context"}],"relatedBlocks":[]},{"id":"b-7c4520c091ca095437cbb5e2","type":"p","scope":"block-5dc1a98878994b8989105349ef7bd0c6","url":"https://codingai-lec03.pages.dev/course/notebooks/23b0affc4b824723927bd0938fd2bbda.html#b-7c4520c091ca095437cbb5e2","content":"$L=\\frac{1}{|\\mathcal M|}\\sum_{i\\in\\mathcal M}\\|\\hat x_i-x_i\\|^2$","sha256":"b5e0f378794cb8b5e98506bac2baa689d3b4fed7d73ae9b28175dfaaf27dbe4b","chapter":{"id":"I","title":"学习信号与表示"},"unit":{"id":"i-reuse-and-targets","title":"训练留下什么，训练答案又从哪里来？"},"page":{"id":"reading-block-5dc1a98878994b8989105349ef7bd0c6","title":"MAE 让昂贵编码器只看少量位置","number":3},"sectionTitle":"MAE 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后忘记恢复顺序，即便预测数值合理，也是在与错误位置的目标比较。排列练习可以证明索引正确；它不能证明编码器已经学会图像语义。","sha256":"3f5dc0bbd2e7534e9bd07a1f682b523e93864d9abfc9188f92d5dc37ff605a01","chapter":{"id":"I","title":"学习信号与表示"},"unit":{"id":"i-reuse-and-targets","title":"训练留下什么，训练答案又从哪里来？"},"page":{"id":"reading-block-5dc1a98878994b8989105349ef7bd0c6","title":"MAE 让昂贵编码器只看少量位置","number":3},"sectionTitle":"MAE 让昂贵编码器只看少量位置","currentQuestion":"MAE 让昂贵编码器只看少量位置","sourceSlides":[],"knowledgeBlock":null,"formulas":[{"latex":"\\mathcal M","definitionContext":"MAE 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计算节省。","sha256":"6d6419fd9b8cf38b3215e50deaae56b50c8735f4332672de31f0b542104500bf","chapter":{"id":"I","title":"学习信号与表示"},"unit":{"id":"i-reuse-and-targets","title":"训练留下什么，训练答案又从哪里来？"},"page":{"id":"reading-block-5dc1a98878994b8989105349ef7bd0c6","title":"MAE 让昂贵编码器只看少量位置","number":3},"sectionTitle":"MAE 让昂贵编码器只看少量位置","currentQuestion":"MAE 让昂贵编码器只看少量位置","sourceSlides":[],"knowledgeBlock":null,"formulas":[],"previousBlock":"b-9c355486e6684f56953b0389","nextBlock":"b-bbfa19c6378704b6ed179dc8","prerequisites":[{"id":"b-0c3f4f1d4bf60563ac95dd53","url":"#b-0c3f4f1d4bf60563ac95dd53","role":"section-title"},{"id":"b-ea05ca62677bd60a465ad3da","url":"#b-ea05ca62677bd60a465ad3da","role":"problem-context"}],"relatedBlocks":[]},{"id":"b-bbfa19c6378704b6ed179dc8","type":"p","scope":"block-5dc1a98878994b8989105349ef7bd0c6","url":"https://codingai-lec03.pages.dev/course/notebooks/23b0affc4b824723927bd0938fd2bbda.html#b-bbfa19c6378704b6ed179dc8","content":"冻结编码器、输入干净保留图像作 5NN，去噪架构由随机初始化的 84.26% 到训练后的 95.00%；遮挡架构由 88.52% 到 92.04%。两种架构输入通道不同，随机基线也应分别保留，不能把它们混成同一个起点。重建改善和读出改善在这次实验中同时出现，但它们仍是两项独立测量。配置、输入 hash 与权重均在 LAB 08 对应材料中。","sha256":"3299792b5c910a1b3a63b2c4677082dda6868df4222b47dc500d9c26add22fe1","chapter":{"id":"I","title":"学习信号与表示"},"unit":{"id":"i-reuse-and-targets","title":"训练留下什么，训练答案又从哪里来？"},"page":{"id":"reading-block-5dc1a98878994b8989105349ef7bd0c6","title":"MAE 让昂贵编码器只看少量位置","number":3},"sectionTitle":"MAE 让昂贵编码器只看少量位置","currentQuestion":"MAE 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会主动要求某些变化在表示中不产生差异。二者的张力是具体的：准确重建颜色需要留下颜色，颜色不变的对比目标却可能鼓励忽略它。好的表示要服务什么，必须由下游问题回答。","sha256":"342160d8a63afceb0d11b164fdae9c202f3e9be639da6a98adb895229b074ebe","chapter":{"id":"I","title":"学习信号与表示"},"unit":{"id":"i-reuse-and-targets","title":"训练留下什么，训练答案又从哪里来？"},"page":{"id":"reading-block-5dc1a98878994b8989105349ef7bd0c6","title":"MAE 让昂贵编码器只看少量位置","number":3},"sectionTitle":"MAE 让昂贵编码器只看少量位置","currentQuestion":"MAE 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读到这里，可以如何继续？","sha256":"04be615138958c4f13e412819a718d3f4afc47be02d77e4b8871d61299bcc9ac","chapter":{"id":"I","title":"学习信号与表示"},"unit":{"id":"i-reuse-and-targets","title":"训练留下什么，训练答案又从哪里来？"},"page":{"id":"reading-block-de414705e5654ffa86fc46358756877d","title":"读到这里，可以如何继续？","number":4},"sectionTitle":"读到这里，可以如何继续？","currentQuestion":"读到这里，可以如何继续？","sourceSlides":[],"knowledgeBlock":null,"formulas":[],"previousBlock":null,"nextBlock":"b-260d8aaf32019c7f477bcb6b","prerequisites":[{"id":"b-260d8aaf32019c7f477bcb6b","url":"#b-260d8aaf32019c7f477bcb6b","role":"problem-context"}],"relatedBlocks":[]},{"id":"b-260d8aaf32019c7f477bcb6b","type":"p","scope":"block-de414705e5654ffa86fc46358756877d","url":"https://codingai-lec03.pages.dev/course/notebooks/23b0affc4b824723927bd0938fd2bbda.html#b-260d8aaf32019c7f477bcb6b","content":"若你能解释“限制输入”与“限制表示”有什么不同，并能给16块示意写出隐藏loss分母，就已完成本册机制主线。接下来选 [LAB 08 · 图像重建：遮挡损失与表示评价](https://deepnote.com/workspace/ise3309jingao-5ba66b0a-4283-4f5a-ae06-3f68d3201e99/project/38755e4e-23f6-4f5f-8c68-8a2e4114b1c1/notebook/b5ba27f2c5ba4ec0922208a7d5dc80a4?utm_source=openai&utm_medium=mcp&utm_campaign=openaimcp&utm_content=b5ba27f2c5ba4ec0922208a7d5dc80a4&utm_term=get_notebook)：先看真实输入、重建、误差，最后读冻结5NN。其模型是masked ConvAE，仍处理稠密网格；原MAE的可见token节省计算由 [少看图块为何省计算，又为何不是固定加速比](/course/blocks/mae-compute-not-sixteen-times.html) 单独解释。","sha256":"0780b00bec94dbc4e96f95a3bf9900917f0d6e14d81049bff765713475e3bb8a","chapter":{"id":"I","title":"学习信号与表示"},"unit":{"id":"i-reuse-and-targets","title":"训练留下什么，训练答案又从哪里来？"},"page":{"id":"reading-block-de414705e5654ffa86fc46358756877d","title":"读到这里，可以如何继续？","number":4},"sectionTitle":"读到这里，可以如何继续？","currentQuestion":"读到这里，可以如何继续？","sourceSlides":[],"knowledgeBlock":null,"formulas":[],"previousBlock":"b-3a992f97494e539edfcef62a","nextBlock":"b-0365516971f31a96dbdeacb5","prerequisites":[{"id":"b-3a992f97494e539edfcef62a","url":"#b-3a992f97494e539edfcef62a","role":"section-title"}],"relatedBlocks":[]},{"id":"b-0365516971f31a96dbdeacb5","type":"p","scope":"block-de414705e5654ffa86fc46358756877d","url":"https://codingai-lec03.pages.dev/course/notebooks/23b0affc4b824723927bd0938fd2bbda.html#b-0365516971f31a96dbdeacb5","content":"只想看一个无需神经网络的实际无标签优化，可选 [LAB 05 · 像素 patch 词典：拟合与重建](https://deepnote.com/workspace/ise3309jingao-5ba66b0a-4283-4f5a-ae06-3f68d3201e99/project/38755e4e-23f6-4f5f-8c68-8a2e4114b1c1/notebook/de39b998077f44cca4b8407085547766?utm_source=openai&utm_medium=mcp&utm_campaign=openaimcp&utm_content=de39b998077f44cca4b8407085547766&utm_term=get_notebook) 的MNIST patch词典。关于教师目标的旧拓展已由 [CLS 06 · 表示的三个检查：目标、信息与新域](https://deepnote.com/workspace/ise3309jingao-5ba66b0a-4283-4f5a-ae06-3f68d3201e99/project/38755e4e-23f6-4f5f-8c68-8a2e4114b1c1/notebook/c0645a4db6e04188ab5b119e87c53bed?utm_source=openai&utm_medium=mcp&utm_campaign=openaimcp&utm_content=c0645a4db6e04188ab5b119e87c53bed&utm_term=get_notebook) 统一组织，不需要在词典实验末尾再学一遍。最后回到 [P23 本页说明](/course/pages/l3-r2-p23.html)：重建好与新任务好，需要分别测量。","sha256":"bc4055cdc99830b8f219631da25dae26736fa6c22ea57660169ddb5b6ac76cde","chapter":{"id":"I","title":"学习信号与表示"},"unit":{"id":"i-reuse-and-targets","title":"训练留下什么，训练答案又从哪里来？"},"page":{"id":"reading-block-de414705e5654ffa86fc46358756877d","title":"读到这里，可以如何继续？","number":4},"sectionTitle":"读到这里，可以如何继续？","currentQuestion":"读到这里，可以如何继续？","sourceSlides":[],"knowledgeBlock":null,"formulas":[],"previousBlock":"b-260d8aaf32019c7f477bcb6b","nextBlock":null,"prerequisites":[{"id":"b-3a992f97494e539edfcef62a","url":"#b-3a992f97494e539edfcef62a","role":"section-title"},{"id":"b-260d8aaf32019c7f477bcb6b","url":"#b-260d8aaf32019c7f477bcb6b","role":"problem-context"}],"relatedBlocks":[]}]}