{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2026:UQN2SR565CSFRKP34B3JVCLXWJ","short_pith_number":"pith:UQN2SR56","canonical_record":{"source":{"id":"2605.21288","kind":"arxiv","version":1},"metadata":{"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"cs.LG","submitted_at":"2026-05-20T15:23:16Z","cross_cats_sorted":[],"title_canon_sha256":"92319c7ea6b2e964e708fa9a2402be0e0e408d9638d7dd808c2423673b9346d1","abstract_canon_sha256":"a099fb70decf3724dfc59419b51533a4027d2197974c932078cc6b5849d03ef9"},"schema_version":"1.0"},"canonical_sha256":"a41ba947bee8a458a9fbe0769a8977b27a9a90f9e53320c7f92dfc70048ab919","source":{"kind":"arxiv","id":"2605.21288","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"2605.21288","created_at":"2026-05-21T02:05:27Z"},{"alias_kind":"arxiv_version","alias_value":"2605.21288v1","created_at":"2026-05-21T02:05:27Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.2605.21288","created_at":"2026-05-21T02:05:27Z"},{"alias_kind":"pith_short_12","alias_value":"UQN2SR565CSF","created_at":"2026-05-21T02:05:27Z"},{"alias_kind":"pith_short_16","alias_value":"UQN2SR565CSFRKP3","created_at":"2026-05-21T02:05:27Z"},{"alias_kind":"pith_short_8","alias_value":"UQN2SR56","created_at":"2026-05-21T02:05:27Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2026:UQN2SR565CSFRKP34B3JVCLXWJ","target":"record","payload":{"canonical_record":{"source":{"id":"2605.21288","kind":"arxiv","version":1},"metadata":{"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"cs.LG","submitted_at":"2026-05-20T15:23:16Z","cross_cats_sorted":[],"title_canon_sha256":"92319c7ea6b2e964e708fa9a2402be0e0e408d9638d7dd808c2423673b9346d1","abstract_canon_sha256":"a099fb70decf3724dfc59419b51533a4027d2197974c932078cc6b5849d03ef9"},"schema_version":"1.0"},"canonical_sha256":"a41ba947bee8a458a9fbe0769a8977b27a9a90f9e53320c7f92dfc70048ab919","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-21T02:05:27.304441Z","signature_b64":"zXmQjQQYKchZwX0qUEmd9wPtFZvuqIr6RnJa/6e28bIJRgpAWaEfhL9fxA6PYjAkR5ynJnzdsJrv75kPFABwAw==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"a41ba947bee8a458a9fbe0769a8977b27a9a90f9e53320c7f92dfc70048ab919","last_reissued_at":"2026-05-21T02:05:27.303730Z","signature_status":"signed_v1","first_computed_at":"2026-05-21T02:05:27.303730Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"2605.21288","source_version":1,"attestation_state":"computed"},"signer":{"signer_id":"pith.science","signer_type":"pith_registry","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"created_at":"2026-05-21T02:05:27Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"kqc/14/ufFGa3jMQc2WHGHDumpRJ/nTroTdyxiJHaB8LW+KN3p5eQibH1+5bsUZVRSDCtz7HhCgP/69tB2GtCA==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-02T04:19:36.159521Z"},"content_sha256":"49694e31b812b30caddcb02c13cb597ea4920f85d4ad862169f7a06879f8f59b","schema_version":"1.0","event_id":"sha256:49694e31b812b30caddcb02c13cb597ea4920f85d4ad862169f7a06879f8f59b"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2026:UQN2SR565CSFRKP34B3JVCLXWJ","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"A Mechanistic Study of Tabular Foundation Models","license":"http://creativecommons.org/licenses/by/4.0/","headline":"","cross_cats":[],"primary_cat":"cs.LG","authors_text":"Anderson Schneider, James T. Wilson, Marin Bilo\\v{s}, Yuriy Nevmyvaka","submitted_at":"2026-05-20T15:23:16Z","abstract_excerpt":"Tabular foundation models with different architectures converge in accuracy across a range of classification and regression tasks. This raises questions a leaderboard cannot answer: (i) whether the models execute the same in-context algorithm, (ii) where row, column, and class-permutation invariances originate, and (iii) how robust they are under perturbations engineered against the inferred mechanism. We characterize all three. The model families realize qualitatively distinct similarity-based readouts: from an attention-weighted vote over context labels to a class-conditional mean readout, e"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2605.21288","kind":"arxiv","version":1},"verdict":{"id":null,"model_set":{},"created_at":null,"strongest_claim":"","one_line_summary":"","pipeline_version":null,"weakest_assumption":"","pith_extraction_headline":""},"integrity":{"clean":true,"summary":{"advisory":0,"critical":0,"by_detector":{},"informational":0},"endpoint":"/pith/2605.21288/integrity.json","findings":[],"available":true,"detectors_run":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938"},"references":{"count":0,"sample":[],"resolved_work":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","internal_anchors":0},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"author_claims":{"count":0,"strong_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"builder_version":"pith-number-builder-2026-05-17-v1"},"verdict_id":null},"signer":{"signer_id":"pith.science","signer_type":"pith_registry","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"created_at":"2026-05-21T02:05:27Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"87BlkHQqx6jMFcKsg2TBQGIcbcfJA2Zt3E2BXoXenXC30Y4yF2FY6eQ+5heIgp6qGG6Rhub8kCj9RuHpRvpVCw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-02T04:19:36.159899Z"},"content_sha256":"d0a4437999f65e729fdc1e1bbb53962dda073adeebfbf1e91607192836e8867b","schema_version":"1.0","event_id":"sha256:d0a4437999f65e729fdc1e1bbb53962dda073adeebfbf1e91607192836e8867b"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/UQN2SR565CSFRKP34B3JVCLXWJ/bundle.json","state_url":"https://pith.science/pith/UQN2SR565CSFRKP34B3JVCLXWJ/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/UQN2SR565CSFRKP34B3JVCLXWJ/bundle.json","status":"primary"}],"public_keys":[{"key_id":"pith-v1-2026-05","algorithm":"ed25519","format":"raw","public_key_b64":"stVStoiQhXFxp4s2pdzPNoqVNBMojDU/fJ2db5S3CbM=","public_key_hex":"b2d552b68890857171a78b36a5dccf368a953413288c353f7c9d9d6f94b709b3","fingerprint_sha256_b32_first128bits":"RVFV5Z2OI2J3ZUO7ERDEBCYNKS","fingerprint_sha256_hex":"8d4b5ee74e4693bcd1df2446408b0d54","rotates_at":null,"url":"https://pith.science/pith-signing-key.json","notes":"Pith uses this Ed25519 key to sign canonical record SHA-256 digests. Verify with: ed25519_verify(public_key, message=canonical_sha256_bytes, signature=base64decode(signature_b64))."}],"merge_version":"pith-open-graph-merge-v1","built_at":"2026-06-02T04:19:36Z","links":{"resolver":"https://pith.science/pith/UQN2SR565CSFRKP34B3JVCLXWJ","bundle":"https://pith.science/pith/UQN2SR565CSFRKP34B3JVCLXWJ/bundle.json","state":"https://pith.science/pith/UQN2SR565CSFRKP34B3JVCLXWJ/state.json","well_known_bundle":"https://pith.science/.well-known/pith/UQN2SR565CSFRKP34B3JVCLXWJ/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2026:UQN2SR565CSFRKP34B3JVCLXWJ","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":"a099fb70decf3724dfc59419b51533a4027d2197974c932078cc6b5849d03ef9","cross_cats_sorted":[],"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"cs.LG","submitted_at":"2026-05-20T15:23:16Z","title_canon_sha256":"92319c7ea6b2e964e708fa9a2402be0e0e408d9638d7dd808c2423673b9346d1"},"schema_version":"1.0","source":{"id":"2605.21288","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"2605.21288","created_at":"2026-05-21T02:05:27Z"},{"alias_kind":"arxiv_version","alias_value":"2605.21288v1","created_at":"2026-05-21T02:05:27Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.2605.21288","created_at":"2026-05-21T02:05:27Z"},{"alias_kind":"pith_short_12","alias_value":"UQN2SR565CSF","created_at":"2026-05-21T02:05:27Z"},{"alias_kind":"pith_short_16","alias_value":"UQN2SR565CSFRKP3","created_at":"2026-05-21T02:05:27Z"},{"alias_kind":"pith_short_8","alias_value":"UQN2SR56","created_at":"2026-05-21T02:05:27Z"}],"graph_snapshots":[{"event_id":"sha256:d0a4437999f65e729fdc1e1bbb53962dda073adeebfbf1e91607192836e8867b","target":"graph","created_at":"2026-05-21T02:05:27Z","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/2605.21288/integrity.json","findings":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938","summary":{"advisory":0,"by_detector":{},"critical":0,"informational":0}},"paper":{"abstract_excerpt":"Tabular foundation models with different architectures converge in accuracy across a range of classification and regression tasks. This raises questions a leaderboard cannot answer: (i) whether the models execute the same in-context algorithm, (ii) where row, column, and class-permutation invariances originate, and (iii) how robust they are under perturbations engineered against the inferred mechanism. We characterize all three. The model families realize qualitatively distinct similarity-based readouts: from an attention-weighted vote over context labels to a class-conditional mean readout, e","authors_text":"Anderson Schneider, James T. Wilson, Marin Bilo\\v{s}, Yuriy Nevmyvaka","cross_cats":[],"headline":"","license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"cs.LG","submitted_at":"2026-05-20T15:23:16Z","title":"A Mechanistic Study of Tabular Foundation Models"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2605.21288","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":"sha256:49694e31b812b30caddcb02c13cb597ea4920f85d4ad862169f7a06879f8f59b","target":"record","created_at":"2026-05-21T02:05:27Z","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":"a099fb70decf3724dfc59419b51533a4027d2197974c932078cc6b5849d03ef9","cross_cats_sorted":[],"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"cs.LG","submitted_at":"2026-05-20T15:23:16Z","title_canon_sha256":"92319c7ea6b2e964e708fa9a2402be0e0e408d9638d7dd808c2423673b9346d1"},"schema_version":"1.0","source":{"id":"2605.21288","kind":"arxiv","version":1}},"canonical_sha256":"a41ba947bee8a458a9fbe0769a8977b27a9a90f9e53320c7f92dfc70048ab919","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"a41ba947bee8a458a9fbe0769a8977b27a9a90f9e53320c7f92dfc70048ab919","first_computed_at":"2026-05-21T02:05:27.303730Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-21T02:05:27.303730Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"zXmQjQQYKchZwX0qUEmd9wPtFZvuqIr6RnJa/6e28bIJRgpAWaEfhL9fxA6PYjAkR5ynJnzdsJrv75kPFABwAw==","signature_status":"signed_v1","signed_at":"2026-05-21T02:05:27.304441Z","signed_message":"canonical_sha256_bytes"},"source_id":"2605.21288","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:49694e31b812b30caddcb02c13cb597ea4920f85d4ad862169f7a06879f8f59b","sha256:d0a4437999f65e729fdc1e1bbb53962dda073adeebfbf1e91607192836e8867b"],"state_sha256":"6f49aeb1d1b6890aaf29f30477ded53f8dc1e530f11ea670eb07b76fcdd71b35"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"g0QBOQbuM/k/msz2G3lKoh6opJR1SoUnNTfP928ch67pkIDThmw3D3TqkU0LjUnPRQwpHWLgrrKYY2R6xmvXAw==","signed_message":"bundle_sha256_bytes","signed_at":"2026-06-02T04:19:36.161973Z","bundle_sha256":"cffd72c103394f20fbdfc922c16412a9046e76a71a044e6c6d490ce8fb6d6562"}}