{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2025:EV672LC5MTH4HAPOTKNOH7PPP7","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":"c786c0929e62cc8d9945556e39457f6cabb5acbe04c607c724b431f1aa9786a5","cross_cats_sorted":["physics.ed-ph"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"stat.ME","submitted_at":"2025-06-12T19:04:53Z","title_canon_sha256":"ff261a7203cb9ff5365afb392680521915ded6b13398fdfa54a77e7909c29d46"},"schema_version":"1.0","source":{"id":"2506.11229","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"2506.11229","created_at":"2026-05-20T00:02:51Z"},{"alias_kind":"arxiv_version","alias_value":"2506.11229v1","created_at":"2026-05-20T00:02:51Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.2506.11229","created_at":"2026-05-20T00:02:51Z"},{"alias_kind":"pith_short_12","alias_value":"EV672LC5MTH4","created_at":"2026-05-20T00:02:51Z"},{"alias_kind":"pith_short_16","alias_value":"EV672LC5MTH4HAPO","created_at":"2026-05-20T00:02:51Z"},{"alias_kind":"pith_short_8","alias_value":"EV672LC5","created_at":"2026-05-20T00:02:51Z"}],"graph_snapshots":[{"event_id":"sha256:9f7efb3b1143ce2cb28af020d243dcce80b206c21e924dcb727b36964417ce28","target":"graph","created_at":"2026-05-20T00:02:51Z","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/2506.11229/integrity.json","findings":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938","summary":{"advisory":0,"by_detector":{},"critical":0,"informational":0}},"paper":{"abstract_excerpt":"Clustering methods are often used in physics education research (PER) to identify subgroups of individuals within a population who share similar response patterns or characteristics. K-means (or k-modes, for categorical data) is one of the most commonly used clustering methods in PER. This algorithm, however, is not model-based: it relies on algorithmic partitioning and assigns individuals to subgroups with definite membership. Researchers must also conduct post-hoc analyses to relate subgroup membership to other variables. Mixture models offer a model-based alternative that accounts for class","authors_text":"Karen Nylund-Gibson, Marsha Ing, Meagan Sundstrom, Minghui Wang","cross_cats":["physics.ed-ph"],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"stat.ME","submitted_at":"2025-06-12T19:04:53Z","title":"Advancing clustering methods in physics education research: A case for mixture models"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2506.11229","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:bfab62b5691f6898d763bb8ad15be777e7d38d9d5c654dd02a6c4fb3082e2f6a","target":"record","created_at":"2026-05-20T00:02:51Z","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":"c786c0929e62cc8d9945556e39457f6cabb5acbe04c607c724b431f1aa9786a5","cross_cats_sorted":["physics.ed-ph"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"stat.ME","submitted_at":"2025-06-12T19:04:53Z","title_canon_sha256":"ff261a7203cb9ff5365afb392680521915ded6b13398fdfa54a77e7909c29d46"},"schema_version":"1.0","source":{"id":"2506.11229","kind":"arxiv","version":1}},"canonical_sha256":"257dfd2c5d64cfc381ee9a9ae3fdef7fc65dddb04663dfddbc5725e45cd9bd67","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"257dfd2c5d64cfc381ee9a9ae3fdef7fc65dddb04663dfddbc5725e45cd9bd67","first_computed_at":"2026-05-20T00:02:51.162761Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-20T00:02:51.162761Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"HlRtGxZH3lFH++FkBli+Ru/XBQXK8ctFmjHmqi5NWwrQmuqmiOnVgpgGexIeXqqiKMB02uShNsKqV8TPYsQ/Dw==","signature_status":"signed_v1","signed_at":"2026-05-20T00:02:51.163804Z","signed_message":"canonical_sha256_bytes"},"source_id":"2506.11229","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:bfab62b5691f6898d763bb8ad15be777e7d38d9d5c654dd02a6c4fb3082e2f6a","sha256:9f7efb3b1143ce2cb28af020d243dcce80b206c21e924dcb727b36964417ce28"],"state_sha256":"f612b8d55097455f70286c36f614240b0d198307782dac4152dfd92a4fe6d226"}