{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2026:ZXPMSMOIGCP5NLFGWQQB53FJTU","merge_version":"pith-open-graph-merge-v1","event_count":2,"valid_event_count":2,"invalid_event_count":0,"equivocation_count":0,"current":{"canonical_record":{"metadata":{"abstract_canon_sha256":"a773d3922875b7c538c17516eef4df447341c21ffe3bb57f099bb552e6450abd","cross_cats_sorted":[],"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"cs.LG","submitted_at":"2026-05-20T12:58:01Z","title_canon_sha256":"6b8b507880695659dc70b987bbb10e272b97b2957da5355f609031a4cc07db30"},"schema_version":"1.0","source":{"id":"2605.21127","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"2605.21127","created_at":"2026-05-21T01:05:38Z"},{"alias_kind":"arxiv_version","alias_value":"2605.21127v1","created_at":"2026-05-21T01:05:38Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.2605.21127","created_at":"2026-05-21T01:05:38Z"},{"alias_kind":"pith_short_12","alias_value":"ZXPMSMOIGCP5","created_at":"2026-05-21T01:05:38Z"},{"alias_kind":"pith_short_16","alias_value":"ZXPMSMOIGCP5NLFG","created_at":"2026-05-21T01:05:38Z"},{"alias_kind":"pith_short_8","alias_value":"ZXPMSMOI","created_at":"2026-05-21T01:05:38Z"}],"graph_snapshots":[{"event_id":"sha256:c0b65cec4059dfbf89bb90e0878421edce8dd4044638fff6e46bed393093f3fc","target":"graph","created_at":"2026-05-21T01:05:38Z","signer":{"key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signer_id":"pith.science","signer_type":"pith_registry"},"payload":{"graph_snapshot":{"author_claims":{"count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","strong_count":0},"builder_version":"pith-number-builder-2026-05-17-v1","claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"integrity":{"available":true,"clean":true,"detectors_run":[],"endpoint":"/pith/2605.21127/integrity.json","findings":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938","summary":{"advisory":0,"by_detector":{},"critical":0,"informational":0}},"paper":{"abstract_excerpt":"Explicit reasoning models are trained to produce intermediate reasoning traces before final answers, but downstream fine-tuning is often performed on ordinary instruction-response data that contains no such traces. We show that this mismatch can induce reasoning-trace collapse: a fine-tuned model continues to produce plausible final answers while losing the structurally valid explicit reasoning traces that made it a reasoning model in the first place. We introduce a structural evaluation framework that separates answer correctness from reasoning-trace validity, measuring valid, empty, missing,","authors_text":"Helen Yannakoudakis, Jie M. Zhang, Lukas Twist","cross_cats":[],"headline":"","license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"cs.LG","submitted_at":"2026-05-20T12:58:01Z","title":"Reasoning-Trace Collapse: Evaluating the Loss of Explicit Reasoning During Fine-Tuning"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2605.21127","kind":"arxiv","version":1},"verdict":{"created_at":null,"id":null,"model_set":{},"one_line_summary":"","pipeline_version":null,"pith_extraction_headline":"","strongest_claim":"","weakest_assumption":""}},"verdict_id":null}}],"author_attestations":[],"timestamp_anchors":[],"storage_attestations":[],"citation_signatures":[],"replication_records":[],"corrections":[],"mirror_hints":[],"record_created":{"event_id":"sha256:d17b4e928dab6a4c8953e1e6800720988632737cdec0402c4cd621be72e6d1e7","target":"record","created_at":"2026-05-21T01:05:38Z","signer":{"key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signer_id":"pith.science","signer_type":"pith_registry"},"payload":{"attestation_state":"computed","canonical_record":{"metadata":{"abstract_canon_sha256":"a773d3922875b7c538c17516eef4df447341c21ffe3bb57f099bb552e6450abd","cross_cats_sorted":[],"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"cs.LG","submitted_at":"2026-05-20T12:58:01Z","title_canon_sha256":"6b8b507880695659dc70b987bbb10e272b97b2957da5355f609031a4cc07db30"},"schema_version":"1.0","source":{"id":"2605.21127","kind":"arxiv","version":1}},"canonical_sha256":"cddec931c8309fd6aca6b4201eeca99d28fecdc4b7e3d30cc7b1bad8453202eb","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"cddec931c8309fd6aca6b4201eeca99d28fecdc4b7e3d30cc7b1bad8453202eb","first_computed_at":"2026-05-21T01:05:38.850790Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-21T01:05:38.850790Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"WJMnkynjF7A7MiA/Wl4ywQMKOw8Hh7fYn+4o6F92cdv7qVr3703fW4Ovk6H4FiFWAJY3LqxKX0Yl7g2hju93DQ==","signature_status":"signed_v1","signed_at":"2026-05-21T01:05:38.851531Z","signed_message":"canonical_sha256_bytes"},"source_id":"2605.21127","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:d17b4e928dab6a4c8953e1e6800720988632737cdec0402c4cd621be72e6d1e7","sha256:c0b65cec4059dfbf89bb90e0878421edce8dd4044638fff6e46bed393093f3fc"],"state_sha256":"32d241e6933115adc27a26a00a6f29245ca4e91d2d545cf3c11e95e729005a24"}