{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2025:7CQ5WH7JVQFF7GXSM3NFI4CPVZ","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":"950e47d31ebfd10bbd1a63aa5ae1981b6276e06f404cdc7eec3add79bf5f523f","cross_cats_sorted":[],"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"physics.ao-ph","submitted_at":"2025-09-10T08:06:24Z","title_canon_sha256":"42a7ca7bb69dd2af02c900aab322133cabb175ff12c52f1faac2cec98bff926a"},"schema_version":"1.0","source":{"id":"2509.08369","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"2509.08369","created_at":"2026-07-05T12:08:28Z"},{"alias_kind":"arxiv_version","alias_value":"2509.08369v1","created_at":"2026-07-05T12:08:28Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.2509.08369","created_at":"2026-07-05T12:08:28Z"},{"alias_kind":"pith_short_12","alias_value":"7CQ5WH7JVQFF","created_at":"2026-07-05T12:08:28Z"},{"alias_kind":"pith_short_16","alias_value":"7CQ5WH7JVQFF7GXS","created_at":"2026-07-05T12:08:28Z"},{"alias_kind":"pith_short_8","alias_value":"7CQ5WH7J","created_at":"2026-07-05T12:08:28Z"}],"graph_snapshots":[{"event_id":"sha256:3fb1c97819562f363ac587e60f5874bd301eec9f0c37443d636eaa44e59375d3","target":"graph","created_at":"2026-07-05T12:08:28Z","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"},"integrity":{"available":true,"clean":true,"detectors_run":[],"endpoint":"/pith/2509.08369/integrity.json","findings":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938","summary":{"advisory":0,"by_detector":{},"critical":0,"informational":0}},"paper":{"abstract_excerpt":"Root-mean-square error (RMSE) remains the default training loss for data-driven precipitation models, despite precipitation being semi-continuous, zero-inflated, strictly non-negative, and heavy-tailed. This Gaussian-implied objective misspecifies the data-generating process because it tolerates negative predictions, underpenalises rare heavy events, and ignores the mass at zero. We propose replacing RMSE with the Tweedie deviance, a likelihood-based and differentiable loss from the exponential--dispersion family with variance function $V(\\mu)=\\mu^p$. For $1<p<2$ it yields a compound Poisson--","authors_text":"Kieran M. R. Hunt","cross_cats":[],"headline":"","license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"physics.ao-ph","submitted_at":"2025-09-10T08:06:24Z","title":"Stop using root-mean-square error as a precipitation target!"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2509.08369","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":"sha256:2746326867751c9b9c4fd98609fefd941fa04ba27768214e7b63d26e82d53437","target":"record","created_at":"2026-07-05T12:08:28Z","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":"950e47d31ebfd10bbd1a63aa5ae1981b6276e06f404cdc7eec3add79bf5f523f","cross_cats_sorted":[],"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"physics.ao-ph","submitted_at":"2025-09-10T08:06:24Z","title_canon_sha256":"42a7ca7bb69dd2af02c900aab322133cabb175ff12c52f1faac2cec98bff926a"},"schema_version":"1.0","source":{"id":"2509.08369","kind":"arxiv","version":1}},"canonical_sha256":"f8a1db1fe9ac0a5f9af266da54704fae45592bd682f292ba11c49b978e662dd6","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"f8a1db1fe9ac0a5f9af266da54704fae45592bd682f292ba11c49b978e662dd6","first_computed_at":"2026-07-05T12:08:28.766985Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-07-05T12:08:28.766985Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"FHxMzpwMeDzkJVAFh496JI/zVdSQx3qmpMGhx7ZTc/zuqipwEZOE/W16Er8O2v+wQbXCqS7+aGjf9e9W0luPDA==","signature_status":"signed_v1","signed_at":"2026-07-05T12:08:28.767517Z","signed_message":"canonical_sha256_bytes"},"source_id":"2509.08369","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:2746326867751c9b9c4fd98609fefd941fa04ba27768214e7b63d26e82d53437","sha256:3fb1c97819562f363ac587e60f5874bd301eec9f0c37443d636eaa44e59375d3"],"state_sha256":"ea0491dd4445dce518749bca83426d36244801b174c771cbc6ed1e59b153fce3"}