Pith Number

pith:TPFQIMGB

pith:2026:TPFQIMGBA4DTKTFM6R357EM4PT

not attested not anchored not stored refs pending

Robust Heteroskedastic Matrix Factorization: A Generalization of PCA that Flags Outliers and Handles Missing Data

Andrew R. Casey, David W. Hogg, Hans-Walter Rix, Thomas Hilder

arxiv:2607.08081 v1 · 2026-07-09 · astro-ph.IM · astro-ph.SR

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

Add to your LaTeX paper

\usepackage{pith}
\pithnumber{TPFQIMGBA4DTKTFM6R357EM4PT}

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	2026-07-10T00:19:09.895363Z
Builder	pith-number-builder-2026-05-17-v1
Signature	Pith Ed25519 (`pith-v1-2026-05`) · public key
Schema	pith-number/v1.0

Canonical hash

9bcb0430c10707354cacf477df919c7cf7f5b4aaa0a907a58f2bd8d9ffbb374c

Aliases

arxiv: 2607.08081 · arxiv_version: 2607.08081v1 · doi: 10.48550/arxiv.2607.08081 · pith_short_12: TPFQIMGBA4DT · pith_short_16: TPFQIMGBA4DTKTFM · pith_short_8: TPFQIMGB

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/TPFQIMGBA4DTKTFM6R357EM4PT \
  | 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: 9bcb0430c10707354cacf477df919c7cf7f5b4aaa0a907a58f2bd8d9ffbb374c

Canonical record JSON

{
  "metadata": {
    "abstract_canon_sha256": "16cfa0b7ec9a91217a714a22343febe9548ad05fa1d50185ea5cd0478ae1e3d0",
    "cross_cats_sorted": [
      "astro-ph.SR"
    ],
    "license": "http://creativecommons.org/licenses/by/4.0/",
    "primary_cat": "astro-ph.IM",
    "submitted_at": "2026-07-09T03:24:23Z",
    "title_canon_sha256": "46b2554f1106cc49611551c3d6d2aa9275540c35214ef175f167081bef23176d"
  },
  "schema_version": "1.0",
  "source": {
    "id": "2607.08081",
    "kind": "arxiv",
    "version": 1
  }
}