Pith Number

pith:OXWH66J6

pith:2026:OXWH66J6PVQFY3CYSL5MGWR5HV

not attested not anchored not stored refs pending

Measuring Research Difficulty of Academic Papers: A Case Study in Natural Language Processing

Chengzhi Zhang, Haochuan Li, Heng Zhang, Jingyuan Li, Yi Zhao, Yukai Yang, Zile Hu

arxiv:2606.25307 v1 · 2026-06-24 · cs.DL · cs.CL · cs.IR

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

Add to your LaTeX paper

\usepackage{pith}
\pithnumber{OXWH66J6PVQFY3CYSL5MGWR5HV}

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	2026-06-25T01:18:01.595635Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

75ec7f793e7d605c6c5892fac35a3d3d431c38dbf3da160f7a5b23e23679f329

Aliases

arxiv: 2606.25307 · arxiv_version: 2606.25307v1 · doi: 10.48550/arxiv.2606.25307 · pith_short_12: OXWH66J6PVQF · pith_short_16: OXWH66J6PVQFY3CY · pith_short_8: OXWH66J6

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/OXWH66J6PVQFY3CYSL5MGWR5HV \
  | 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: 75ec7f793e7d605c6c5892fac35a3d3d431c38dbf3da160f7a5b23e23679f329

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "68cc2857475c8cddccab25fae77f3c6406d86acf7606fbba449969b135994cb4",
    "cross_cats_sorted": [
      "cs.CL",
      "cs.IR"
    ],
    "license": "http://creativecommons.org/licenses/by/4.0/",
    "primary_cat": "cs.DL",
    "submitted_at": "2026-06-24T02:22:08Z",
    "title_canon_sha256": "9af882daa28d4bb1585b06b775e7e2478a007bb35dad7c7c6fced4fa02f4e726"
  },
  "schema_version": "1.0",
  "source": {
    "id": "2606.25307",
    "kind": "arxiv",
    "version": 1
  }
}