{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2014:4RO6WF2ZYPPGVAOSYP2PWK257U","short_pith_number":"pith:4RO6WF2Z","canonical_record":{"source":{"id":"1406.3396","kind":"arxiv","version":2},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"q-fin.PM","submitted_at":"2014-06-13T00:52:52Z","cross_cats_sorted":["q-fin.RM"],"title_canon_sha256":"fcafb2974a237e75147cdd9a50af3cb49707e7320b0dfaf971ef476b529ce9c8","abstract_canon_sha256":"2ce7f4df9c7b5621e8a537bd07d5015615c439fbabd0586eb0b0134710bbf924"},"schema_version":"1.0"},"canonical_sha256":"e45deb1759c3de6a81d2c3f4fb2b5dfd14dd5e2b74d6a078d0a04b23ce507cc9","source":{"kind":"arxiv","id":"1406.3396","version":2},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1406.3396","created_at":"2026-05-18T02:32:31Z"},{"alias_kind":"arxiv_version","alias_value":"1406.3396v2","created_at":"2026-05-18T02:32:31Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1406.3396","created_at":"2026-05-18T02:32:31Z"},{"alias_kind":"pith_short_12","alias_value":"4RO6WF2ZYPPG","created_at":"2026-05-18T12:28:14Z"},{"alias_kind":"pith_short_16","alias_value":"4RO6WF2ZYPPGVAOS","created_at":"2026-05-18T12:28:14Z"},{"alias_kind":"pith_short_8","alias_value":"4RO6WF2Z","created_at":"2026-05-18T12:28:14Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2014:4RO6WF2ZYPPGVAOSYP2PWK257U","target":"record","payload":{"canonical_record":{"source":{"id":"1406.3396","kind":"arxiv","version":2},"metadata":{"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"q-fin.PM","submitted_at":"2014-06-13T00:52:52Z","cross_cats_sorted":["q-fin.RM"],"title_canon_sha256":"fcafb2974a237e75147cdd9a50af3cb49707e7320b0dfaf971ef476b529ce9c8","abstract_canon_sha256":"2ce7f4df9c7b5621e8a537bd07d5015615c439fbabd0586eb0b0134710bbf924"},"schema_version":"1.0"},"canonical_sha256":"e45deb1759c3de6a81d2c3f4fb2b5dfd14dd5e2b74d6a078d0a04b23ce507cc9","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-05-18T02:32:31.596705Z","signature_b64":"R8zBXtDDZrji2gRUsC/v4STgVMH0rd2qYEJUV3flZwt3qADh+HzKVuZd5AKcaKhoweWiH1L4MKkiSQU9o4/KAA==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"e45deb1759c3de6a81d2c3f4fb2b5dfd14dd5e2b74d6a078d0a04b23ce507cc9","last_reissued_at":"2026-05-18T02:32:31.596300Z","signature_status":"signed_v1","first_computed_at":"2026-05-18T02:32:31.596300Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"1406.3396","source_version":2,"attestation_state":"computed"},"signer":{"signer_id":"pith.science","signer_type":"pith_registry","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"created_at":"2026-05-18T02:32:31Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"ziNTbhwFVeGmJ3uAsF1jF/nJBRS7z1uIXLtno8N7QpXYTK4JB4BLdB9F0zlVHiF7bwqJKfdcZuJtZpw1AqUKCg==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-23T02:58:08.053223Z"},"content_sha256":"467e2e10953509b804a6d3d8e554447e7fb92acfbcedae10546d7a5133037b6b","schema_version":"1.0","event_id":"sha256:467e2e10953509b804a6d3d8e554447e7fb92acfbcedae10546d7a5133037b6b"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2014:4RO6WF2ZYPPGVAOSYP2PWK257U","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Factor Models for Alpha Streams","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["q-fin.RM"],"primary_cat":"q-fin.PM","authors_text":"Zura Kakushadze","submitted_at":"2014-06-13T00:52:52Z","abstract_excerpt":"We propose a framework for constructing factor models for alpha streams. Our motivation is threefold. 1) When the number of alphas is large, the sample covariance matrix is singular. 2) Its out-of-sample stability is challenging. 3) Optimization of investment allocation into alpha streams can be tractable for a factor model alpha covariance matrix. We discuss various risk factors for alphas such as: style risk factors; cluster risk factors based on alpha taxonomy; principal components; and also using the underlying tradables (stocks) as alpha risk factors, for which computing the factor loadin"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1406.3396","kind":"arxiv","version":2},"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":"2026-05-18T02:32:31Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"OOx459EQi3L98Zu/Z3SlaWHsXfhBw/oM5b2g84imBGilvHKsqUsLNRuZfJti+KMtAI9lIPYlRa2MWSkCcAt4Aw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-05-23T02:58:08.053928Z"},"content_sha256":"b2032787d7ac93a332c347334f82ed0c6c4574067ae9320d48b6d00dbb1a8f51","schema_version":"1.0","event_id":"sha256:b2032787d7ac93a332c347334f82ed0c6c4574067ae9320d48b6d00dbb1a8f51"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/4RO6WF2ZYPPGVAOSYP2PWK257U/bundle.json","state_url":"https://pith.science/pith/4RO6WF2ZYPPGVAOSYP2PWK257U/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/4RO6WF2ZYPPGVAOSYP2PWK257U/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":"2026-05-23T02:58:08Z","links":{"resolver":"https://pith.science/pith/4RO6WF2ZYPPGVAOSYP2PWK257U","bundle":"https://pith.science/pith/4RO6WF2ZYPPGVAOSYP2PWK257U/bundle.json","state":"https://pith.science/pith/4RO6WF2ZYPPGVAOSYP2PWK257U/state.json","well_known_bundle":"https://pith.science/.well-known/pith/4RO6WF2ZYPPGVAOSYP2PWK257U/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2014:4RO6WF2ZYPPGVAOSYP2PWK257U","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":"2ce7f4df9c7b5621e8a537bd07d5015615c439fbabd0586eb0b0134710bbf924","cross_cats_sorted":["q-fin.RM"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"q-fin.PM","submitted_at":"2014-06-13T00:52:52Z","title_canon_sha256":"fcafb2974a237e75147cdd9a50af3cb49707e7320b0dfaf971ef476b529ce9c8"},"schema_version":"1.0","source":{"id":"1406.3396","kind":"arxiv","version":2}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"1406.3396","created_at":"2026-05-18T02:32:31Z"},{"alias_kind":"arxiv_version","alias_value":"1406.3396v2","created_at":"2026-05-18T02:32:31Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.1406.3396","created_at":"2026-05-18T02:32:31Z"},{"alias_kind":"pith_short_12","alias_value":"4RO6WF2ZYPPG","created_at":"2026-05-18T12:28:14Z"},{"alias_kind":"pith_short_16","alias_value":"4RO6WF2ZYPPGVAOS","created_at":"2026-05-18T12:28:14Z"},{"alias_kind":"pith_short_8","alias_value":"4RO6WF2Z","created_at":"2026-05-18T12:28:14Z"}],"graph_snapshots":[{"event_id":"sha256:b2032787d7ac93a332c347334f82ed0c6c4574067ae9320d48b6d00dbb1a8f51","target":"graph","created_at":"2026-05-18T02:32:31Z","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":"We propose a framework for constructing factor models for alpha streams. Our motivation is threefold. 1) When the number of alphas is large, the sample covariance matrix is singular. 2) Its out-of-sample stability is challenging. 3) Optimization of investment allocation into alpha streams can be tractable for a factor model alpha covariance matrix. We discuss various risk factors for alphas such as: style risk factors; cluster risk factors based on alpha taxonomy; principal components; and also using the underlying tradables (stocks) as alpha risk factors, for which computing the factor loadin","authors_text":"Zura Kakushadze","cross_cats":["q-fin.RM"],"headline":"","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"q-fin.PM","submitted_at":"2014-06-13T00:52:52Z","title":"Factor Models for Alpha Streams"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1406.3396","kind":"arxiv","version":2},"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":"sha256:467e2e10953509b804a6d3d8e554447e7fb92acfbcedae10546d7a5133037b6b","target":"record","created_at":"2026-05-18T02:32:31Z","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":"2ce7f4df9c7b5621e8a537bd07d5015615c439fbabd0586eb0b0134710bbf924","cross_cats_sorted":["q-fin.RM"],"license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","primary_cat":"q-fin.PM","submitted_at":"2014-06-13T00:52:52Z","title_canon_sha256":"fcafb2974a237e75147cdd9a50af3cb49707e7320b0dfaf971ef476b529ce9c8"},"schema_version":"1.0","source":{"id":"1406.3396","kind":"arxiv","version":2}},"canonical_sha256":"e45deb1759c3de6a81d2c3f4fb2b5dfd14dd5e2b74d6a078d0a04b23ce507cc9","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"e45deb1759c3de6a81d2c3f4fb2b5dfd14dd5e2b74d6a078d0a04b23ce507cc9","first_computed_at":"2026-05-18T02:32:31.596300Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-05-18T02:32:31.596300Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"R8zBXtDDZrji2gRUsC/v4STgVMH0rd2qYEJUV3flZwt3qADh+HzKVuZd5AKcaKhoweWiH1L4MKkiSQU9o4/KAA==","signature_status":"signed_v1","signed_at":"2026-05-18T02:32:31.596705Z","signed_message":"canonical_sha256_bytes"},"source_id":"1406.3396","source_kind":"arxiv","source_version":2}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:467e2e10953509b804a6d3d8e554447e7fb92acfbcedae10546d7a5133037b6b","sha256:b2032787d7ac93a332c347334f82ed0c6c4574067ae9320d48b6d00dbb1a8f51"],"state_sha256":"9e390f3de7ae84dca39995546761c7ab279bf15c4b4d05568193a2a7f4cdc55e"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"FWD9ptXEW2bxAIEgQVeNv8ReNCBWxjmgPh+JzQbBtAd1fHwMu9D5q8TP3i0D9216bInJlZzP17QT4+ta7RMeAg==","signed_message":"bundle_sha256_bytes","signed_at":"2026-05-23T02:58:08.057673Z","bundle_sha256":"d406a139450b3f014a455cec242be81718441ac63636a063254ac10049ba74fc"}}