{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2019:CFY24N6GIJRVEWBFBZQMA63WGC","short_pith_number":"pith:CFY24N6G","canonical_record":{"source":{"id":"1907.11620","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.SI","submitted_at":"2019-06-12T09:24:04Z","cross_cats_sorted":["cs.IR"],"title_canon_sha256":"1e54b472c0654cdaabd3e34ab08e858306bfbb8bcb2a46be88d497d34e8b6a70","abstract_canon_sha256":"58360e9f25963d486b81246e29d55fbb6170bc4649ae995f25b63f2c6674a5a7"},"schema_version":"1.0"},"canonical_sha256":"1171ae37c642635258250e60c07b7630aee066bf27cae93f8de827c3fa073678","source":{"kind":"arxiv","id":"1907.11620","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1907.11620","created_at":"2026-05-17T23:39:28Z"},{"alias_kind":"arxiv_version","alias_value":"1907.11620v1","created_at":"2026-05-17T23:39:28Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1907.11620","created_at":"2026-05-17T23:39:28Z"},{"alias_kind":"pith_short_12","alias_value":"CFY24N6GIJRV","created_at":"2026-05-18T12:33:12Z"},{"alias_kind":"pith_short_16","alias_value":"CFY24N6GIJRVEWBF","created_at":"2026-05-18T12:33:12Z"},{"alias_kind":"pith_short_8","alias_value":"CFY24N6G","created_at":"2026-05-18T12:33:12Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2019:CFY24N6GIJRVEWBFBZQMA63WGC","target":"record","payload":{"canonical_record":{"source":{"id":"1907.11620","kind":"arxiv","version":1},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.SI","submitted_at":"2019-06-12T09:24:04Z","cross_cats_sorted":["cs.IR"],"title_canon_sha256":"1e54b472c0654cdaabd3e34ab08e858306bfbb8bcb2a46be88d497d34e8b6a70","abstract_canon_sha256":"58360e9f25963d486b81246e29d55fbb6170bc4649ae995f25b63f2c6674a5a7"},"schema_version":"1.0"},"canonical_sha256":"1171ae37c642635258250e60c07b7630aee066bf27cae93f8de827c3fa073678","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-17T23:39:28.532841Z","signature_b64":"posiPXXokk6UOYN9vu+riRNiI5XQGfpXmSuZylBKKucPyImXEaNYwxR6AN1eRxdgLM/z7TLij+nSn1zJ5i/ECA==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"1171ae37c642635258250e60c07b7630aee066bf27cae93f8de827c3fa073678","last_reissued_at":"2026-05-17T23:39:28.532059Z","signature_status":"signed_v1","first_computed_at":"2026-05-17T23:39:28.532059Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1907.11620","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":"2026-05-17T23:39:28Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"JcghSJcST4yn0o8L60LH/U59Q2/PY9Fs3HNQ/YUDWiZxezxkD8J3L+NhesQ2IgA/XtlSiLNDlF4C1GuniFBCAQ==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-18T19:25:17.892193Z"},"content_sha256":"32a51dde477384ff24115d9bddb8d932ec83f09aad0f751a342317d07ec7ce65","schema_version":"1.0","event_id":"sha256:32a51dde477384ff24115d9bddb8d932ec83f09aad0f751a342317d07ec7ce65"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2019:CFY24N6GIJRVEWBFBZQMA63WGC","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Exploiting weak ties in trust-based recommender systems using regular equivalence","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["cs.IR"],"primary_cat":"cs.SI","authors_text":"Dominik Kowald, Elisabeth Lex, Emanuel Lacic, Tomislav Duricic","submitted_at":"2019-06-12T09:24:04Z","abstract_excerpt":"User-based Collaborative Filtering (CF) is one of the most popular approaches to create recommender systems. CF, however, suffers from data sparsity and the cold-start problem since users often rate only a small fraction of available items. One solution is to incorporate additional information into the recommendation process such as explicit trust scores that are assigned by users to others or implicit trust relationships that result from social connections between users. Such relationships typically form a very sparse trust network, which can be utilized to generate recommendations for users "},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1907.11620","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":"2026-05-17T23:39:28Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"/TebG9b5TSDlE9xGUmMLPkS/8Blg7b+FedGK/O1co+FCviRVTbuXKOYU4Srkn2SY8dTalHuEc99qsXPzLIXvDA==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-18T19:25:17.892564Z"},"content_sha256":"de32e9b207965cf94fdeb512abc44d1c5648be59f9f82ab4caa228d4e01341bd","schema_version":"1.0","event_id":"sha256:de32e9b207965cf94fdeb512abc44d1c5648be59f9f82ab4caa228d4e01341bd"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/CFY24N6GIJRVEWBFBZQMA63WGC/bundle.json","state_url":"https://pith.science/pith/CFY24N6GIJRVEWBFBZQMA63WGC/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/CFY24N6GIJRVEWBFBZQMA63WGC/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":"2026-05-18T19:25:17Z","links":{"resolver":"https://pith.science/pith/CFY24N6GIJRVEWBFBZQMA63WGC","bundle":"https://pith.science/pith/CFY24N6GIJRVEWBFBZQMA63WGC/bundle.json","state":"https://pith.science/pith/CFY24N6GIJRVEWBFBZQMA63WGC/state.json","well_known_bundle":"https://pith.science/.well-known/pith/CFY24N6GIJRVEWBFBZQMA63WGC/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2019:CFY24N6GIJRVEWBFBZQMA63WGC","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":"58360e9f25963d486b81246e29d55fbb6170bc4649ae995f25b63f2c6674a5a7","cross_cats_sorted":["cs.IR"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.SI","submitted_at":"2019-06-12T09:24:04Z","title_canon_sha256":"1e54b472c0654cdaabd3e34ab08e858306bfbb8bcb2a46be88d497d34e8b6a70"},"schema_version":"1.0","source":{"id":"1907.11620","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1907.11620","created_at":"2026-05-17T23:39:28Z"},{"alias_kind":"arxiv_version","alias_value":"1907.11620v1","created_at":"2026-05-17T23:39:28Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1907.11620","created_at":"2026-05-17T23:39:28Z"},{"alias_kind":"pith_short_12","alias_value":"CFY24N6GIJRV","created_at":"2026-05-18T12:33:12Z"},{"alias_kind":"pith_short_16","alias_value":"CFY24N6GIJRVEWBF","created_at":"2026-05-18T12:33:12Z"},{"alias_kind":"pith_short_8","alias_value":"CFY24N6G","created_at":"2026-05-18T12:33:12Z"}],"graph_snapshots":[{"event_id":"sha256:de32e9b207965cf94fdeb512abc44d1c5648be59f9f82ab4caa228d4e01341bd","target":"graph","created_at":"2026-05-17T23:39:28Z","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":"User-based Collaborative Filtering (CF) is one of the most popular approaches to create recommender systems. CF, however, suffers from data sparsity and the cold-start problem since users often rate only a small fraction of available items. One solution is to incorporate additional information into the recommendation process such as explicit trust scores that are assigned by users to others or implicit trust relationships that result from social connections between users. Such relationships typically form a very sparse trust network, which can be utilized to generate recommendations for users ","authors_text":"Dominik Kowald, Elisabeth Lex, Emanuel Lacic, Tomislav Duricic","cross_cats":["cs.IR"],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.SI","submitted_at":"2019-06-12T09:24:04Z","title":"Exploiting weak ties in trust-based recommender systems using regular equivalence"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1907.11620","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":"sha256:32a51dde477384ff24115d9bddb8d932ec83f09aad0f751a342317d07ec7ce65","target":"record","created_at":"2026-05-17T23:39:28Z","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":"58360e9f25963d486b81246e29d55fbb6170bc4649ae995f25b63f2c6674a5a7","cross_cats_sorted":["cs.IR"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"cs.SI","submitted_at":"2019-06-12T09:24:04Z","title_canon_sha256":"1e54b472c0654cdaabd3e34ab08e858306bfbb8bcb2a46be88d497d34e8b6a70"},"schema_version":"1.0","source":{"id":"1907.11620","kind":"arxiv","version":1}},"canonical_sha256":"1171ae37c642635258250e60c07b7630aee066bf27cae93f8de827c3fa073678","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"1171ae37c642635258250e60c07b7630aee066bf27cae93f8de827c3fa073678","first_computed_at":"2026-05-17T23:39:28.532059Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-17T23:39:28.532059Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"posiPXXokk6UOYN9vu+riRNiI5XQGfpXmSuZylBKKucPyImXEaNYwxR6AN1eRxdgLM/z7TLij+nSn1zJ5i/ECA==","signature_status":"signed_v1","signed_at":"2026-05-17T23:39:28.532841Z","signed_message":"canonical_sha256_bytes"},"source_id":"1907.11620","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:32a51dde477384ff24115d9bddb8d932ec83f09aad0f751a342317d07ec7ce65","sha256:de32e9b207965cf94fdeb512abc44d1c5648be59f9f82ab4caa228d4e01341bd"],"state_sha256":"b6e2280aa757e11ea5e30a6ff15fc4cce64dcf802f5d9f86cf9a39a257db9d55"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"qBGrg4hf63L6ZtQnLdHQjUcXgS4rPS6szaiFkDLPOdSQ2+2NAcrXBlJQdg/7Vxe/Bd6gS4Y7RHXPTyU6GXxpDA==","signed_message":"bundle_sha256_bytes","signed_at":"2026-05-18T19:25:17.894037Z","bundle_sha256":"0a493cffecd7a9e2b2c4f92e1de03705add12f6899675f54d5948c83d05c67fc"}}