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Its DRIFT mechanism schedules a per-token convex mixture of forward-KL and reverse-KL surrogate objectives on student-sampled trajectories (per-token surrogates, not sequence-level KL gradient estimators). Six components extend it: (A) COVA, a coverage-adaptive $\\beta$ schedule accelerating the forward-to-reverse transition; (B) FTB, a forking-token boost concentrating gradient ","title":"CADENCE: Closing the Reasoning Gap via Coverage-Adaptive On-Policy Distillation","url":"https://arxiv.org/abs/2607.16955","vendor":"arxiv_cs_ai"},"summary":"arXiv:2607.16955v1 Announce Type: cross \nAbstract: On-policy knowledge distillation transfers reasoning from large teachers to compact students, but existing approaches suffer three compounding failure modes: (i) cold-start collapse, where a fresh student assigns near-zero mass to teacher-preferred tokens; (ii) state-agnostic divergence scheduling, where time-only forward/reverse-KL interpolation ignores the student's coverage state; and (iii) binary reward sparsity, where pass/fail signals discard information from partially correct traces.\n  We present CADENCE, a unified framework with a targeted fix for each. 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Six components extend it: (A) COVA, a coverage-adaptive $\\beta$ schedule accelerating the forward-to-reverse transition; (B) FTB, a forking-token boost concentrating gradient ","title":"CADENCE: Closing the Reasoning Gap via Coverage-Adaptive On-Policy Distillation","vendor":"arxiv_cs_ai"},"confidence":{"method":"deterministic"},"decision":"POSITIVE","issued_at":"2026-07-21T04:43:35Z","notes":"Spider vendor_press (news) news.vendor_press.v1","object":{"captured_by":"crovia.spider.vendor_press","primary_source_url":"https://arxiv.org/abs/2607.16955"},"predecessors":[],"schema":"crovia.axiom.v1","signature":"ed25519:b0b2592ab09617dc39210d36a45ebe8b75b0bba3e4cddb8c583244e009467dd0ba6643911fee71ba77eb7f5e40dd543c4863e3b6c96e52b01f434107b98bb609","signer":"crovia.substrate","subject":{"observed_at":"2026-07-21T04:43:35Z","source_collector":"spider:vendor_press","target_id":"https://arxiv.org/abs/2607.16955"},"tsa":{"authority":"crovia.substrate.bootstrap","rfc3161_token":"{\"kind\":\"crovia.bootstrap.tsa\",\"source_jsonl\":\"/opt/crovia/spider/data/news/vendor_press_v1.jsonl\",\"source_seal_merkle_root\":\"spider_vendor_press_v1\",\"upgrade_path\":\"Sessione H \\u2014 OpenTimestamps weekly anchor\"}"},"zk_mode":"clear","zk_proof":null},"ledger":{"leaf_hash":"719615b892d2092fe7a01b0ffc5b05a54966af71a215ed2fe46cc31fbfbfc06d","leaf_index":336732,"ledger_path":"/opt/crovia/substrate/axiom_ledger.jsonl"},"merkle_proof":{"hash_alg":"sha256","leaf_prefix":"0x00","node_prefix":"0x01","odd_leaf_rule":"duplicate_last","path":[{"sibling":"f35189eeadb053919315662ca412bef0c81625bb66b39b414273d2ecde9b51bf","side":"right"},{"sibling":"925fdf0250f9628b6cfc6f00b6893cbe3194e4b7972ff373afe5096dc800f90e","side":"right"},{"sibling":"a10a6e708165e56c68073b2a4eb34f9be4102cf5cab44c470d1ebc4450baeaec","side":"left"},{"sibling":"c9dd25d0ae15d43fc0a115a713b9c6a19c34ea93041f7f9d7660b7f8c071071e","side":"left"},{"sibling":"f0061fcafbf8e6a8152bfbef71e4b13ad9956e1985fbb8157db2c1f947936e44","side":"left"},{"sibling":"a67d55fd22cd262abeda1495d0d2509734cbc60bb2980c0014022699d323696d","side":"right"},{"sibling":"c3453c4355287f8f6ea5b33a2f2d95f482fa4ede383b4407cc8d044e332ee8e5","side":"left"},{"sibling":"a4c41a614872a391d764732d35b746845ccfe3f2a51fe13e1f0e934d271e94f4","side":"right"},{"sibling":"bd233cee8c0876447824d86de33608c36e3a8e17dca0737155291ed768cf56d1","side":"left"},{"sibling":"7b927551b5db06b6571913b4e6792ffcce5291a3eca5a0df4a3b6e296271105f","side":"left"},{"sibling":"b77a0b5ae4607c8fe6ba73449d46b35076e3dedc0c82a2c65a05780d42a7bc2e","side":"right"},{"sibling":"9eb5077edfb3dc553857d4794b925bfce117e0f8a1d049af5d0dd9026b470eef","side":"right"},{"sibling":"414b1a70fd1dcb25489a194714b97492b066684b15d0b7a48a176c4b9b5bc713","side":"right"},{"sibling":"21d66dd41003813f710b7617944f1bfba3258658a5d3370c21cad8f9e945bc99","side":"left"},{"sibling":"613f015699131eb89bd755dee67133be95af25cf5f16c1c8ce4b99d963b8dd86","side":"right"},{"sibling":"a729b574b1135956436ded5eef1fe8f08014ff6a0729749d307ab1bca93fcdc9","side":"right"},{"sibling":"77025bcb374a7ad74f520643e20a8ae1205a7ee78507b0beb93117760f1c29d3","side":"left"},{"sibling":"4bf21052e085e8ac81f1dec1d2b310bd12bf948992de6177d12e9d2fda8d39f0","side":"right"},{"sibling":"1cecb7f447febd025aac272837c80de218aecc6485d2395a509b2a1f1b9c746e","side":"left"}]},"schema":"crovia.axiom_proof.v1","seal":{"first_collector_run_id":"","first_receipt_hash":"","jsonl_path":"/opt/crovia/substrate/axiom_ledger.jsonl","key_id":"430895f101d38164","last_collector_run_id":"","last_receipt_hash":"","leaf_count":337144,"merkle_root":"5e969cc01afa67e4dbe5d37b712cdb10f4aa1fd74404e02eab724cf487c8d6d9","public_key_hex":"cf742e26f75669dc673cb5c0786a1ae23ae8ca19c347317192ce40c28a7ff25c","run_id":"hourly_json_retrofit_20260721T053701Z","schema":"crovia.seal.v1","seal_family_version":"crovia-seal-family/1","seal_kind":"substrate_batch","sealed_at":"2026-07-21T05:38:38Z","sig_algorithm":"ed25519","signature":"5c0c1a8dd2793d787ccd5e49e8b4d70eed136352555518589f05c74be357fc171702e42a76c3a556d90e3d51ff36cb3d292aaac83c66566de7b943f318bda50c","signer_version":"1.1.0"},"trust_root":{"key_id":"430895f101d38164","public_key_hex":"cf742e26f75669dc673cb5c0786a1ae23ae8ca19c347317192ce40c28a7ff25c","signature_algorithm":"ed25519","url":"/registry/canon/TRUST_ROOT.md"},"verifier":{"spec":"/registry/canon/AXIOM_RECEIPT_v1.md","url":"/v/axm_9482944487d124b1bcb7f27cd16d8dd64fb4120d6ae47cfa7d224aea4eba84cb"}}