Pith Number

pith:YMBNB7RH

pith:2025:YMBNB7RH3QKDPR27VPEQFBQUZR

not attested not anchored not stored refs pending

Model Error Covariance Estimation for Weak Constraint Data Assimilation

Donna Calhoun, Jodi Mead, Patricia O. Azike, Sandra R. Babyale

arxiv:2504.17900 v1 · 2025-04-24 · stat.ME · cs.NA · math.NA · math.OC

Open paper page JSON Open Graph Bundle Merged state Verified badge What is a Pith Number?

Add to your LaTeX paper

\usepackage{pith}
\pithnumber{YMBNB7RH3QKDPR27VPEQFBQUZR}

Prints a linked badge after your title and injects PDF metadata. Compiles on arXiv. Learn more · Embed verified badge

Record completeness

1 Bitcoin timestamp

2 Internet Archive

3 Author claim open · sign in to claim

4 Citations open

5 Replications open

✓ Portable graph bundle live · download bundle · merged state

The bundle contains the canonical record plus signed events. A mirror can host it anywhere and recompute the same current state with the deterministic merge algorithm.

Receipt and verification

First computed	2026-07-05T10:53:58.412109Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

c302d0fe27dc1437c75fabc9028614cc4c10611c05353fcac7e40dc628a30024

Aliases

arxiv: 2504.17900 · arxiv_version: 2504.17900v1 · doi: 10.48550/arxiv.2504.17900 · pith_short_12: YMBNB7RH3QKD · pith_short_16: YMBNB7RH3QKDPR27 · pith_short_8: YMBNB7RH

Agent API

Resolver JSON Graph JSON Events JSON Schema Signing key

Verify this Pith Number yourself

curl -sH 'Accept: application/ld+json' https://pith.science/pith/YMBNB7RH3QKDPR27VPEQFBQUZR \
  | jq -c '.canonical_record' \
  | python3 -c "import sys,json,hashlib; b=json.dumps(json.loads(sys.stdin.read()), sort_keys=True, separators=(',',':'), ensure_ascii=False).encode(); print(hashlib.sha256(b).hexdigest())"
# expect: c302d0fe27dc1437c75fabc9028614cc4c10611c05353fcac7e40dc628a30024

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "db426245fdcb4fe629c8fb596a3e631a4a05b6abad7d8d9d89f51b26053ba250",
    "cross_cats_sorted": [
      "cs.NA",
      "math.NA",
      "math.OC"
    ],
    "license": "http://creativecommons.org/licenses/by-nc-nd/4.0/",
    "primary_cat": "stat.ME",
    "submitted_at": "2025-04-24T19:22:10Z",
    "title_canon_sha256": "4b0a5875be808233dbfb9d514ad9b1f9b63591e09f068414b8dc1696ca57a0b9"
  },
  "schema_version": "1.0",
  "source": {
    "id": "2504.17900",
    "kind": "arxiv",
    "version": 1
  }
}