{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2011:N2RICZECSCNSDE2BAM72B7XO2S","short_pith_number":"pith:N2RICZEC","canonical_record":{"source":{"id":"1111.1570","kind":"arxiv","version":1},"metadata":{"license":"http://creativecommons.org/licenses/by/3.0/","primary_cat":"cs.IR","submitted_at":"2011-11-07T13:31:39Z","cross_cats_sorted":["cs.SI"],"title_canon_sha256":"e92aba8a800e86f4f2f9961101ab572057127cccb700874806ff05777bdf71c2","abstract_canon_sha256":"6c51947362aeaa04ff7fbc63185d5b5f5aeb448fecf57c45eac5b5db4267067c"},"schema_version":"1.0"},"canonical_sha256":"6ea2816482909b219341033fa0feeed4a1af27c7d22f934cf31e929a203e2e58","source":{"kind":"arxiv","id":"1111.1570","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1111.1570","created_at":"2026-05-18T04:09:25Z"},{"alias_kind":"arxiv_version","alias_value":"1111.1570v1","created_at":"2026-05-18T04:09:25Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1111.1570","created_at":"2026-05-18T04:09:25Z"},{"alias_kind":"pith_short_12","alias_value":"N2RICZECSCNS","created_at":"2026-05-18T12:26:37Z"},{"alias_kind":"pith_short_16","alias_value":"N2RICZECSCNSDE2B","created_at":"2026-05-18T12:26:37Z"},{"alias_kind":"pith_short_8","alias_value":"N2RICZEC","created_at":"2026-05-18T12:26:37Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2011:N2RICZECSCNSDE2BAM72B7XO2S","target":"record","payload":{"canonical_record":{"source":{"id":"1111.1570","kind":"arxiv","version":1},"metadata":{"license":"http://creativecommons.org/licenses/by/3.0/","primary_cat":"cs.IR","submitted_at":"2011-11-07T13:31:39Z","cross_cats_sorted":["cs.SI"],"title_canon_sha256":"e92aba8a800e86f4f2f9961101ab572057127cccb700874806ff05777bdf71c2","abstract_canon_sha256":"6c51947362aeaa04ff7fbc63185d5b5f5aeb448fecf57c45eac5b5db4267067c"},"schema_version":"1.0"},"canonical_sha256":"6ea2816482909b219341033fa0feeed4a1af27c7d22f934cf31e929a203e2e58","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T04:09:25.784083Z","signature_b64":"Q2ZDWh0jez74CkJTSCX5ouMc3CB6xC2YzZbzuV/TPzQf6H1b7Uxtseq5krR2gQgV4c6ZedRG6CSVHjyJyA70CQ==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"6ea2816482909b219341033fa0feeed4a1af27c7d22f934cf31e929a203e2e58","last_reissued_at":"2026-05-18T04:09:25.783445Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T04:09:25.783445Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1111.1570","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":"2026-05-18T04:09:25Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"MESpNM1JTkKYbxNv+XyUemfE1hEqfcSkAO6SAf2CDf/kbIk7G3dnx3N0Ow4wUFGnqGK7h3vigH45JBalh4ZWAQ==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-22T20:29:00.163450Z"},"content_sha256":"8c5cbc193754631c42ea504fc1763f46b63b279cd79b9a57692d3e95aea92148","schema_version":"1.0","event_id":"sha256:8c5cbc193754631c42ea504fc1763f46b63b279cd79b9a57692d3e95aea92148"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2011:N2RICZECSCNSDE2BAM72B7XO2S","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Semantic Grounding Strategies for Tagbased Recommender Systems","license":"http://creativecommons.org/licenses/by/3.0/","headline":"","cross_cats":["cs.SI"],"primary_cat":"cs.IR","authors_text":"Frederico Durao, Peter Dolog","submitted_at":"2011-11-07T13:31:39Z","abstract_excerpt":"Recommender systems usually operate on similarities between recommended items or users. Tag based recommender systems utilize similarities on tags. The tags are however mostly free user entered phrases. Therefore, similarities computed without their semantic groundings might lead to less relevant recommendations. In this paper, we study a semantic grounding used for tag similarity calculus. We show a comprehensive analysis of semantic grounding given by 20 ontologies from different domains. The study besides other things reveals that currently available OWL ontologies are very narrow and the p"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1111.1570","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":"2026-05-18T04:09:25Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"NAi/yM6Fvwr/B318dx2qXKRwcgGLDpJgpoFqCrotLtNrCWac7LiV6W9shRQGVfyIziCKnnTWFU21TM9a1o+DDg==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-06-22T20:29:00.163807Z"},"content_sha256":"9a624bdd655530edec2227c3d4a0b3ec9cb8e36221668219717d7bd82e5ae8a0","schema_version":"1.0","event_id":"sha256:9a624bdd655530edec2227c3d4a0b3ec9cb8e36221668219717d7bd82e5ae8a0"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/N2RICZECSCNSDE2BAM72B7XO2S/bundle.json","state_url":"https://pith.science/pith/N2RICZECSCNSDE2BAM72B7XO2S/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/N2RICZECSCNSDE2BAM72B7XO2S/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":"2026-06-22T20:29:00Z","links":{"resolver":"https://pith.science/pith/N2RICZECSCNSDE2BAM72B7XO2S","bundle":"https://pith.science/pith/N2RICZECSCNSDE2BAM72B7XO2S/bundle.json","state":"https://pith.science/pith/N2RICZECSCNSDE2BAM72B7XO2S/state.json","well_known_bundle":"https://pith.science/.well-known/pith/N2RICZECSCNSDE2BAM72B7XO2S/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2011:N2RICZECSCNSDE2BAM72B7XO2S","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":"6c51947362aeaa04ff7fbc63185d5b5f5aeb448fecf57c45eac5b5db4267067c","cross_cats_sorted":["cs.SI"],"license":"http://creativecommons.org/licenses/by/3.0/","primary_cat":"cs.IR","submitted_at":"2011-11-07T13:31:39Z","title_canon_sha256":"e92aba8a800e86f4f2f9961101ab572057127cccb700874806ff05777bdf71c2"},"schema_version":"1.0","source":{"id":"1111.1570","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1111.1570","created_at":"2026-05-18T04:09:25Z"},{"alias_kind":"arxiv_version","alias_value":"1111.1570v1","created_at":"2026-05-18T04:09:25Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1111.1570","created_at":"2026-05-18T04:09:25Z"},{"alias_kind":"pith_short_12","alias_value":"N2RICZECSCNS","created_at":"2026-05-18T12:26:37Z"},{"alias_kind":"pith_short_16","alias_value":"N2RICZECSCNSDE2B","created_at":"2026-05-18T12:26:37Z"},{"alias_kind":"pith_short_8","alias_value":"N2RICZEC","created_at":"2026-05-18T12:26:37Z"}],"graph_snapshots":[{"event_id":"sha256:9a624bdd655530edec2227c3d4a0b3ec9cb8e36221668219717d7bd82e5ae8a0","target":"graph","created_at":"2026-05-18T04:09:25Z","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":"Recommender systems usually operate on similarities between recommended items or users. Tag based recommender systems utilize similarities on tags. The tags are however mostly free user entered phrases. Therefore, similarities computed without their semantic groundings might lead to less relevant recommendations. In this paper, we study a semantic grounding used for tag similarity calculus. We show a comprehensive analysis of semantic grounding given by 20 ontologies from different domains. The study besides other things reveals that currently available OWL ontologies are very narrow and the p","authors_text":"Frederico Durao, Peter Dolog","cross_cats":["cs.SI"],"headline":"","license":"http://creativecommons.org/licenses/by/3.0/","primary_cat":"cs.IR","submitted_at":"2011-11-07T13:31:39Z","title":"Semantic Grounding Strategies for Tagbased Recommender Systems"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1111.1570","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":"sha256:8c5cbc193754631c42ea504fc1763f46b63b279cd79b9a57692d3e95aea92148","target":"record","created_at":"2026-05-18T04:09:25Z","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":"6c51947362aeaa04ff7fbc63185d5b5f5aeb448fecf57c45eac5b5db4267067c","cross_cats_sorted":["cs.SI"],"license":"http://creativecommons.org/licenses/by/3.0/","primary_cat":"cs.IR","submitted_at":"2011-11-07T13:31:39Z","title_canon_sha256":"e92aba8a800e86f4f2f9961101ab572057127cccb700874806ff05777bdf71c2"},"schema_version":"1.0","source":{"id":"1111.1570","kind":"arxiv","version":1}},"canonical_sha256":"6ea2816482909b219341033fa0feeed4a1af27c7d22f934cf31e929a203e2e58","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"6ea2816482909b219341033fa0feeed4a1af27c7d22f934cf31e929a203e2e58","first_computed_at":"2026-05-18T04:09:25.783445Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T04:09:25.783445Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"Q2ZDWh0jez74CkJTSCX5ouMc3CB6xC2YzZbzuV/TPzQf6H1b7Uxtseq5krR2gQgV4c6ZedRG6CSVHjyJyA70CQ==","signature_status":"signed_v1","signed_at":"2026-05-18T04:09:25.784083Z","signed_message":"canonical_sha256_bytes"},"source_id":"1111.1570","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:8c5cbc193754631c42ea504fc1763f46b63b279cd79b9a57692d3e95aea92148","sha256:9a624bdd655530edec2227c3d4a0b3ec9cb8e36221668219717d7bd82e5ae8a0"],"state_sha256":"5c1c9515f1dce37bd9022e44e2c396d2a81d903cb0380670fba170ee48b17ec9"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"qXAhvXXFu8V7zpu9XJWNw+Pu2YfEIPrz7j1un5GI6CnU9uSEsoRB3+EB8bDkHXAyZPI70iEArOtlJZ8ONFioAQ==","signed_message":"bundle_sha256_bytes","signed_at":"2026-06-22T20:29:00.165832Z","bundle_sha256":"823726a2c8fae83f682510bb7066d0a22600688b36eccf52097ab476ecbff9a3"}}