{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2011:7GSUW4NNMJZBUPQLKGIQ3YXNL6","short_pith_number":"pith:7GSUW4NN","canonical_record":{"source":{"id":"1107.5095","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"q-bio.PE","submitted_at":"2011-07-25T23:39:25Z","cross_cats_sorted":[],"title_canon_sha256":"60f0c71d0644a75277a298eff13d471fdc81144d6eb608024138bbdbeecd6ee1","abstract_canon_sha256":"6a9be5b435f1ef556719a19efd97af440c80cf7e16a172c705a48958007a5fd7"},"schema_version":"1.0"},"canonical_sha256":"f9a54b71ad62721a3e0b51910de2ed5f9b00e30c6f45de55271fcc2ad0340ba6","source":{"kind":"arxiv","id":"1107.5095","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1107.5095","created_at":"2026-05-18T04:16:53Z"},{"alias_kind":"arxiv_version","alias_value":"1107.5095v1","created_at":"2026-05-18T04:16:53Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1107.5095","created_at":"2026-05-18T04:16:53Z"},{"alias_kind":"pith_short_12","alias_value":"7GSUW4NNMJZB","created_at":"2026-05-18T12:26:22Z"},{"alias_kind":"pith_short_16","alias_value":"7GSUW4NNMJZBUPQL","created_at":"2026-05-18T12:26:22Z"},{"alias_kind":"pith_short_8","alias_value":"7GSUW4NN","created_at":"2026-05-18T12:26:22Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2011:7GSUW4NNMJZBUPQLKGIQ3YXNL6","target":"record","payload":{"canonical_record":{"source":{"id":"1107.5095","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"q-bio.PE","submitted_at":"2011-07-25T23:39:25Z","cross_cats_sorted":[],"title_canon_sha256":"60f0c71d0644a75277a298eff13d471fdc81144d6eb608024138bbdbeecd6ee1","abstract_canon_sha256":"6a9be5b435f1ef556719a19efd97af440c80cf7e16a172c705a48958007a5fd7"},"schema_version":"1.0"},"canonical_sha256":"f9a54b71ad62721a3e0b51910de2ed5f9b00e30c6f45de55271fcc2ad0340ba6","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T04:16:53.056293Z","signature_b64":"A4PTdLnlRS7QkfawC24HLUnnTYsFVduGFaAS/Z7Nz5ZtSLPA+TWDXZdd5caTgzMiSq3rMXLJ19SFA40cL/BXBQ==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"f9a54b71ad62721a3e0b51910de2ed5f9b00e30c6f45de55271fcc2ad0340ba6","last_reissued_at":"2026-05-18T04:16:53.055646Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T04:16:53.055646Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1107.5095","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":"2026-05-18T04:16:53Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"LIQga0nCWx6+1oTaJBx26VVq+EIT8kWc4v9s6TjKQXqYWvpoA4uJoDlC8ZlPkA02xv+obCJ40T48JtA8zIbTDQ==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-30T12:09:23.835601Z"},"content_sha256":"d30d2f43ef6595b3dbb5378a46276b6a232fbe8b2375e711a845c0b6fb8db865","schema_version":"1.0","event_id":"sha256:d30d2f43ef6595b3dbb5378a46276b6a232fbe8b2375e711a845c0b6fb8db865"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2011:7GSUW4NNMJZBUPQLKGIQ3YXNL6","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Edge principal components and squash clustering: using the special structure of phylogenetic placement data for sample comparison","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":[],"primary_cat":"q-bio.PE","authors_text":"Frederick A. Matsen, Steven N. Evans","submitted_at":"2011-07-25T23:39:25Z","abstract_excerpt":"Principal components (PCA) and hierarchical clustering are two of the most heavily used techniques for analyzing the differences between nucleic acid sequence samples sampled from a given environment. However, a classical application of these techniques to distances computed between samples can lack transparency because there is no ready interpretation of the axes of classical PCA plots, and it is difficult to assign any clear intuitive meaning to either the internal nodes or the edge lengths of trees produced by distance-based hierarchical clustering methods such as UPGMA. We show that more i"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1107.5095","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":""},"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":"2026-05-18T04:16:53Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"1S48ZYhS3B9XHUn+iXqmYmPksGxP0KoCv1U5Xue1At5KEwyWqszkznph/BPtb6wf8RsY9GehqYXyv4CT5jqTBw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-30T12:09:23.836226Z"},"content_sha256":"df0a5794eb36dbc7dc8dc6ace74d8706deada0e97d8ed44fb4b75009e45126a3","schema_version":"1.0","event_id":"sha256:df0a5794eb36dbc7dc8dc6ace74d8706deada0e97d8ed44fb4b75009e45126a3"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/7GSUW4NNMJZBUPQLKGIQ3YXNL6/bundle.json","state_url":"https://pith.science/pith/7GSUW4NNMJZBUPQLKGIQ3YXNL6/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/7GSUW4NNMJZBUPQLKGIQ3YXNL6/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":"2026-05-30T12:09:23Z","links":{"resolver":"https://pith.science/pith/7GSUW4NNMJZBUPQLKGIQ3YXNL6","bundle":"https://pith.science/pith/7GSUW4NNMJZBUPQLKGIQ3YXNL6/bundle.json","state":"https://pith.science/pith/7GSUW4NNMJZBUPQLKGIQ3YXNL6/state.json","well_known_bundle":"https://pith.science/.well-known/pith/7GSUW4NNMJZBUPQLKGIQ3YXNL6/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2011:7GSUW4NNMJZBUPQLKGIQ3YXNL6","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":"6a9be5b435f1ef556719a19efd97af440c80cf7e16a172c705a48958007a5fd7","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"q-bio.PE","submitted_at":"2011-07-25T23:39:25Z","title_canon_sha256":"60f0c71d0644a75277a298eff13d471fdc81144d6eb608024138bbdbeecd6ee1"},"schema_version":"1.0","source":{"id":"1107.5095","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1107.5095","created_at":"2026-05-18T04:16:53Z"},{"alias_kind":"arxiv_version","alias_value":"1107.5095v1","created_at":"2026-05-18T04:16:53Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1107.5095","created_at":"2026-05-18T04:16:53Z"},{"alias_kind":"pith_short_12","alias_value":"7GSUW4NNMJZB","created_at":"2026-05-18T12:26:22Z"},{"alias_kind":"pith_short_16","alias_value":"7GSUW4NNMJZBUPQL","created_at":"2026-05-18T12:26:22Z"},{"alias_kind":"pith_short_8","alias_value":"7GSUW4NN","created_at":"2026-05-18T12:26:22Z"}],"graph_snapshots":[{"event_id":"sha256:df0a5794eb36dbc7dc8dc6ace74d8706deada0e97d8ed44fb4b75009e45126a3","target":"graph","created_at":"2026-05-18T04:16:53Z","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"},"paper":{"abstract_excerpt":"Principal components (PCA) and hierarchical clustering are two of the most heavily used techniques for analyzing the differences between nucleic acid sequence samples sampled from a given environment. However, a classical application of these techniques to distances computed between samples can lack transparency because there is no ready interpretation of the axes of classical PCA plots, and it is difficult to assign any clear intuitive meaning to either the internal nodes or the edge lengths of trees produced by distance-based hierarchical clustering methods such as UPGMA. We show that more i","authors_text":"Frederick A. Matsen, Steven N. Evans","cross_cats":[],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"q-bio.PE","submitted_at":"2011-07-25T23:39:25Z","title":"Edge principal components and squash clustering: using the special structure of phylogenetic placement data for sample comparison"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1107.5095","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:d30d2f43ef6595b3dbb5378a46276b6a232fbe8b2375e711a845c0b6fb8db865","target":"record","created_at":"2026-05-18T04:16:53Z","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":"6a9be5b435f1ef556719a19efd97af440c80cf7e16a172c705a48958007a5fd7","cross_cats_sorted":[],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"q-bio.PE","submitted_at":"2011-07-25T23:39:25Z","title_canon_sha256":"60f0c71d0644a75277a298eff13d471fdc81144d6eb608024138bbdbeecd6ee1"},"schema_version":"1.0","source":{"id":"1107.5095","kind":"arxiv","version":1}},"canonical_sha256":"f9a54b71ad62721a3e0b51910de2ed5f9b00e30c6f45de55271fcc2ad0340ba6","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"f9a54b71ad62721a3e0b51910de2ed5f9b00e30c6f45de55271fcc2ad0340ba6","first_computed_at":"2026-05-18T04:16:53.055646Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T04:16:53.055646Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"A4PTdLnlRS7QkfawC24HLUnnTYsFVduGFaAS/Z7Nz5ZtSLPA+TWDXZdd5caTgzMiSq3rMXLJ19SFA40cL/BXBQ==","signature_status":"signed_v1","signed_at":"2026-05-18T04:16:53.056293Z","signed_message":"canonical_sha256_bytes"},"source_id":"1107.5095","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:d30d2f43ef6595b3dbb5378a46276b6a232fbe8b2375e711a845c0b6fb8db865","sha256:df0a5794eb36dbc7dc8dc6ace74d8706deada0e97d8ed44fb4b75009e45126a3"],"state_sha256":"934508bbefa766e7b68438ff7db203e24d549c0734aa7d1f808d4f6498b7e56b"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"m02NnoJVS8mWR2OxCmh7f+JCr7BNFcZk0CHZNA6xUbxmZUdqD4FIoJMserc1JWXoMzqTUmo0M+u1xcdCIpfGBw==","signed_message":"bundle_sha256_bytes","signed_at":"2026-05-30T12:09:23.839670Z","bundle_sha256":"27a0995e3994298c5dd18a0af41e4d8447ed7fb94efe399874f6c078410b463d"}}