{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2014:72K6BOWL2EDUMVDPOIB6THE3C5","short_pith_number":"pith:72K6BOWL","canonical_record":{"source":{"id":"1403.1600","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"stat.ML","submitted_at":"2014-03-06T21:51:48Z","cross_cats_sorted":["cs.IT","cs.LG","math.IT"],"title_canon_sha256":"fd332933705a72f7548908902c9d07b6b9e3845a956d0535181666ee5d9badb2","abstract_canon_sha256":"5457374c60d815db8b226b7beb198df89c3ba6f43815140ca0186b6f1e659563"},"schema_version":"1.0"},"canonical_sha256":"fe95e0bacbd10746546f7203e99c9b17720c574a28c74fa3a6de405131b487fd","source":{"kind":"arxiv","id":"1403.1600","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1403.1600","created_at":"2026-05-18T02:56:53Z"},{"alias_kind":"arxiv_version","alias_value":"1403.1600v1","created_at":"2026-05-18T02:56:53Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1403.1600","created_at":"2026-05-18T02:56:53Z"},{"alias_kind":"pith_short_12","alias_value":"72K6BOWL2EDU","created_at":"2026-05-18T12:28:16Z"},{"alias_kind":"pith_short_16","alias_value":"72K6BOWL2EDUMVDP","created_at":"2026-05-18T12:28:16Z"},{"alias_kind":"pith_short_8","alias_value":"72K6BOWL","created_at":"2026-05-18T12:28:16Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2014:72K6BOWL2EDUMVDPOIB6THE3C5","target":"record","payload":{"canonical_record":{"source":{"id":"1403.1600","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"stat.ML","submitted_at":"2014-03-06T21:51:48Z","cross_cats_sorted":["cs.IT","cs.LG","math.IT"],"title_canon_sha256":"fd332933705a72f7548908902c9d07b6b9e3845a956d0535181666ee5d9badb2","abstract_canon_sha256":"5457374c60d815db8b226b7beb198df89c3ba6f43815140ca0186b6f1e659563"},"schema_version":"1.0"},"canonical_sha256":"fe95e0bacbd10746546f7203e99c9b17720c574a28c74fa3a6de405131b487fd","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T02:56:53.002221Z","signature_b64":"76IIsdPiCYwHpxhb5R76zWfISBsFC5nwx1oOcjO4TGoqoUupqDvLlh+qaeU7QwqLDVQYDuyMeMZMAfaYIw5wCQ==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"fe95e0bacbd10746546f7203e99c9b17720c574a28c74fa3a6de405131b487fd","last_reissued_at":"2026-05-18T02:56:53.001755Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T02:56:53.001755Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1403.1600","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":"2026-05-18T02:56:53Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"G2pyw0yfLGFA+hRjULtdjgcLqK+wP4yhmBg/+wLzoVetEBUofztNe9NR7j9TC1IDv/vrqTdQjmlUCATD6ZdXCQ==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-08T03:06:04.230263Z"},"content_sha256":"1ca1ddd6360a6beef74c595d88a46cc6c9a7cce7cf77d7d59d8efcf3783bc7e5","schema_version":"1.0","event_id":"sha256:1ca1ddd6360a6beef74c595d88a46cc6c9a7cce7cf77d7d59d8efcf3783bc7e5"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2014:72K6BOWL2EDUMVDPOIB6THE3C5","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Collaborative Filtering with Information-Rich and Information-Sparse Entities","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["cs.IT","cs.LG","math.IT"],"primary_cat":"stat.ML","authors_text":"Kai Zhu, Lei Ying, R. Srikant, Rui Wu","submitted_at":"2014-03-06T21:51:48Z","abstract_excerpt":"In this paper, we consider a popular model for collaborative filtering in recommender systems where some users of a website rate some items, such as movies, and the goal is to recover the ratings of some or all of the unrated items of each user. In particular, we consider both the clustering model, where only users (or items) are clustered, and the co-clustering model, where both users and items are clustered, and further, we assume that some users rate many items (information-rich users) and some users rate only a few items (information-sparse users). When users (or items) are clustered, our "},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1403.1600","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":"2026-05-18T02:56:53Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"6jMrUo+ZqBLJ1Mh84S4Mlce+hL6NlgTMcvvhBe7/BJb8TJ/QDKrBc+2cCg+ZCOOM0w+kj6pNREWEeprfsVZaCQ==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-08T03:06:04.230891Z"},"content_sha256":"5bb11eeb99214bb5e27125244ee703992e4ba581a5450116129f00ab17656af7","schema_version":"1.0","event_id":"sha256:5bb11eeb99214bb5e27125244ee703992e4ba581a5450116129f00ab17656af7"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/72K6BOWL2EDUMVDPOIB6THE3C5/bundle.json","state_url":"https://pith.science/pith/72K6BOWL2EDUMVDPOIB6THE3C5/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/72K6BOWL2EDUMVDPOIB6THE3C5/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":"2026-06-08T03:06:04Z","links":{"resolver":"https://pith.science/pith/72K6BOWL2EDUMVDPOIB6THE3C5","bundle":"https://pith.science/pith/72K6BOWL2EDUMVDPOIB6THE3C5/bundle.json","state":"https://pith.science/pith/72K6BOWL2EDUMVDPOIB6THE3C5/state.json","well_known_bundle":"https://pith.science/.well-known/pith/72K6BOWL2EDUMVDPOIB6THE3C5/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2014:72K6BOWL2EDUMVDPOIB6THE3C5","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":"5457374c60d815db8b226b7beb198df89c3ba6f43815140ca0186b6f1e659563","cross_cats_sorted":["cs.IT","cs.LG","math.IT"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"stat.ML","submitted_at":"2014-03-06T21:51:48Z","title_canon_sha256":"fd332933705a72f7548908902c9d07b6b9e3845a956d0535181666ee5d9badb2"},"schema_version":"1.0","source":{"id":"1403.1600","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1403.1600","created_at":"2026-05-18T02:56:53Z"},{"alias_kind":"arxiv_version","alias_value":"1403.1600v1","created_at":"2026-05-18T02:56:53Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1403.1600","created_at":"2026-05-18T02:56:53Z"},{"alias_kind":"pith_short_12","alias_value":"72K6BOWL2EDU","created_at":"2026-05-18T12:28:16Z"},{"alias_kind":"pith_short_16","alias_value":"72K6BOWL2EDUMVDP","created_at":"2026-05-18T12:28:16Z"},{"alias_kind":"pith_short_8","alias_value":"72K6BOWL","created_at":"2026-05-18T12:28:16Z"}],"graph_snapshots":[{"event_id":"sha256:5bb11eeb99214bb5e27125244ee703992e4ba581a5450116129f00ab17656af7","target":"graph","created_at":"2026-05-18T02:56:53Z","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":"In this paper, we consider a popular model for collaborative filtering in recommender systems where some users of a website rate some items, such as movies, and the goal is to recover the ratings of some or all of the unrated items of each user. In particular, we consider both the clustering model, where only users (or items) are clustered, and the co-clustering model, where both users and items are clustered, and further, we assume that some users rate many items (information-rich users) and some users rate only a few items (information-sparse users). When users (or items) are clustered, our ","authors_text":"Kai Zhu, Lei Ying, R. Srikant, Rui Wu","cross_cats":["cs.IT","cs.LG","math.IT"],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"stat.ML","submitted_at":"2014-03-06T21:51:48Z","title":"Collaborative Filtering with Information-Rich and Information-Sparse Entities"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1403.1600","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":"sha256:1ca1ddd6360a6beef74c595d88a46cc6c9a7cce7cf77d7d59d8efcf3783bc7e5","target":"record","created_at":"2026-05-18T02:56:53Z","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":"5457374c60d815db8b226b7beb198df89c3ba6f43815140ca0186b6f1e659563","cross_cats_sorted":["cs.IT","cs.LG","math.IT"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"stat.ML","submitted_at":"2014-03-06T21:51:48Z","title_canon_sha256":"fd332933705a72f7548908902c9d07b6b9e3845a956d0535181666ee5d9badb2"},"schema_version":"1.0","source":{"id":"1403.1600","kind":"arxiv","version":1}},"canonical_sha256":"fe95e0bacbd10746546f7203e99c9b17720c574a28c74fa3a6de405131b487fd","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"fe95e0bacbd10746546f7203e99c9b17720c574a28c74fa3a6de405131b487fd","first_computed_at":"2026-05-18T02:56:53.001755Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T02:56:53.001755Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"76IIsdPiCYwHpxhb5R76zWfISBsFC5nwx1oOcjO4TGoqoUupqDvLlh+qaeU7QwqLDVQYDuyMeMZMAfaYIw5wCQ==","signature_status":"signed_v1","signed_at":"2026-05-18T02:56:53.002221Z","signed_message":"canonical_sha256_bytes"},"source_id":"1403.1600","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:1ca1ddd6360a6beef74c595d88a46cc6c9a7cce7cf77d7d59d8efcf3783bc7e5","sha256:5bb11eeb99214bb5e27125244ee703992e4ba581a5450116129f00ab17656af7"],"state_sha256":"3b2951a7021ad30ca0addfaf39f8f04d11107a1fe83d25f3dff6dfd8c7ee764a"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"aNufQo9ICGUf9p985S1GGgmiA2TzgY5IJJ6juIw528YSRD9b8uA5+JIUKqO1XvN018V8DStJ90RCsJ/D/uPwCQ==","signed_message":"bundle_sha256_bytes","signed_at":"2026-06-08T03:06:04.234245Z","bundle_sha256":"a166b0a4c4aa8fb86036eb94a04e1fc8364d6e273f45a5abe016cd36757bdd8c"}}