Pith Number

pith:QQTDDJVK

pith:2009:QQTDDJVKFFVSPY55WOKVEAGETQ

not attested not anchored not stored refs pending

Efficient Learning of Sparse Conditional Random Fields for Supervised Sequence Labelling

Fran\c{c}ois Yvon (LIMSI), Nataliya Sokolovska (LTCI), Olivier Capp\'e (LTCI), Thomas Lavergne (LIMSI)

arxiv:0909.1308 v2 · 2009-09-07 · cs.LG · cs.CL

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

Add to your LaTeX paper

\usepackage{pith}
\pithnumber{QQTDDJVKFFVSPY55WOKVEAGETQ}

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	2026-05-18T02:11:58.856362Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

842631a6aa296b27e3bdb3955200c49c25b0348dce23dbec9fb4df115fc09b97

Aliases

arxiv: 0909.1308 · arxiv_version: 0909.1308v2 · doi: 10.48550/arxiv.0909.1308 · pith_short_12: QQTDDJVKFFVS · pith_short_16: QQTDDJVKFFVSPY55 · pith_short_8: QQTDDJVK

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/QQTDDJVKFFVSPY55WOKVEAGETQ \
  | 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: 842631a6aa296b27e3bdb3955200c49c25b0348dce23dbec9fb4df115fc09b97

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "51228a20a6514f7872d2747baeae8acd5a03b1195033a5c9581669e2bb3fbdab",
    "cross_cats_sorted": [
      "cs.CL"
    ],
    "license": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
    "primary_cat": "cs.LG",
    "submitted_at": "2009-09-07T18:48:42Z",
    "title_canon_sha256": "cc5d638287720259cd8a856c5c01d24127d050a6ffaaf68e63b29e869d5092b9"
  },
  "schema_version": "1.0",
  "source": {
    "id": "0909.1308",
    "kind": "arxiv",
    "version": 2
  }
}