Pith Number

pith:2QFZS4IY

pith:2021:2QFZS4IYOHN7AJEPZMAZKQOIWH

not attested not anchored not stored refs pending

Cross-validation: what does it estimate and how well does it do it?

Robert Tibshirani, Stephen Bates, Trevor Hastie

arxiv:2104.00673 v4 · 2021-04-01 · stat.ME · math.ST · stat.CO · stat.ML · stat.TH

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

Add to your LaTeX paper

\usepackage{pith}
\pithnumber{2QFZS4IYOHN7AJEPZMAZKQOIWH}

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	2026-07-05T07:53:57.071986Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

d40b99711871dbf0248fcb019541c8b1d08b340b0584cd31c74cff789bb554f0

Aliases

arxiv: 2104.00673 · arxiv_version: 2104.00673v4 · doi: 10.48550/arxiv.2104.00673 · pith_short_12: 2QFZS4IYOHN7 · pith_short_16: 2QFZS4IYOHN7AJEP · pith_short_8: 2QFZS4IY

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/2QFZS4IYOHN7AJEPZMAZKQOIWH \
  | 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: d40b99711871dbf0248fcb019541c8b1d08b340b0584cd31c74cff789bb554f0

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "a5809c0d2af45c62fc14cad8cad73ce4bfa5092edc0384aed6c622531b57d295",
    "cross_cats_sorted": [
      "math.ST",
      "stat.CO",
      "stat.ML",
      "stat.TH"
    ],
    "license": "http://creativecommons.org/licenses/by/4.0/",
    "primary_cat": "stat.ME",
    "submitted_at": "2021-04-01T17:58:54Z",
    "title_canon_sha256": "9bdcb50c6478f64be0c5c5e3e8ecac4c2dd925336dc54521dfe1b23008d1f682"
  },
  "schema_version": "1.0",
  "source": {
    "id": "2104.00673",
    "kind": "arxiv",
    "version": 4
  }
}