Pith Number

pith:D6VH4J5F

pith:2009:D6VH4J5FIXOI3XQMEXIPY5CLGI

not attested not anchored not stored refs pending

Cross-Validation for Unsupervised Learning

Patrick O. Perry

arxiv:0909.3052 v1 · 2009-09-16 · stat.ME · math.ST · 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{D6VH4J5FIXOI3XQMEXIPY5CLGI}

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	2026-07-04T15:49:47.143746Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

1faa7e27a545dc8dde0c25d0fc744b3224932caf13f779adce49ac29ba0f76b3

Aliases

arxiv: 0909.3052 · arxiv_version: 0909.3052v1 · doi: 10.48550/arxiv.0909.3052 · pith_short_12: D6VH4J5FIXOI · pith_short_16: D6VH4J5FIXOI3XQM · pith_short_8: D6VH4J5F

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/D6VH4J5FIXOI3XQMEXIPY5CLGI \
  | 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: 1faa7e27a545dc8dde0c25d0fc744b3224932caf13f779adce49ac29ba0f76b3

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "aaf2f72f9f94efd9c5c1645b20abc8e9120c67001565f1592e8ff70d7c04a4c5",
    "cross_cats_sorted": [
      "math.ST",
      "stat.TH"
    ],
    "license": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
    "primary_cat": "stat.ME",
    "submitted_at": "2009-09-16T16:16:48Z",
    "title_canon_sha256": "949d0f348911489a92e49779c8ae8259557e4dfc267b5ef018fed0b33f2d5847"
  },
  "schema_version": "1.0",
  "source": {
    "id": "0909.3052",
    "kind": "arxiv",
    "version": 1
  }
}