gbanyan c8c7656513 Apply codex round-22 corrections to §III v3 (Minor -> ready)
Codex gpt-5.5 round 22 returned Minor Revision after v2 closed
3/5 Major findings fully and 2/5 partially. Five narrow fixes
applied for v3:

  1. Per-firm ranking unanimity corrected (v2:93). The reverse-
     anchor score ranks Firm D fractionally higher than Firm C
     (-0.7125 vs -0.7672); only Scores 1 and 3 rank Firm C
     highest. The unanimity claim was wrong; v3 prose now says
     all three agree on Firm A as most replication-dominated
     and on the non-Firm-A Big-4 as more hand-leaning, with a
     modest disagreement on Firm C vs D ordering.

  2. "Smallest scope" / "any single firm" overclaim narrowed
     (v2:21, v2:43). Script 32 only tested Firm A alone, big4_non_A
     pooled, and all_non_A pooled -- not Firms B, C, D individually.
     v3 explicitly says "comparison scopes tested in Script 32"
     and notes single-firm dip tests for B, C, D were not
     separately computed.

  3. K=3 hard label vs posterior in Spearman correctly
     attributed (v2:143). Script 38 uses the K=3 posterior P(C1),
     not the hard label, in the internal-consistency Spearman
     correlations. v3 §III-L now correctly says the hard label
     is for the §IV cluster cross-tabulation while the posterior
     is the continuous Score 1 in §III-K.

  4. Provenance source for n=150,442 corrected (v2:17, v2:152).
     Script 39 directly reports this count in its per-signature
     K=3 fit; Script 38's report does not. v3 cites Script 39 for
     this number.

  5. "Max fold-to-fold deviation" wording made precise (v2:65,
     v2:107). The $0.028$ value is the max absolute deviation
     from the across-fold mean (Script 36 stability summary), not
     the pairwise across-fold range (which is $0.0376 = 0.9756 -
     0.9380$). v3 reports both statistics with explicit
     definitions.

Also: draft note at top now records v2 (round-21) and v3
(round-22) revision lineage. Cross-reference index and open-
question block retained as author working checklist (will be
removed before manuscript submission per codex e7).

Outstanding open questions reduced to 3 (codex round-22 view):
  - Five-way moderate-confidence band: validate in Big-4 specifically
    (Phase 3 §IV-F work) or document as inherited from v3.x?
  - Firm anonymisation policy in §IV-V (procedural)
  - §IV table numbering (procedural; defer until §IV done)

Phase 2 §III draft is now Minor-Revision-quality. Ready for
Phase 3 (Results regeneration §IV).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
2026-05-12 16:26:02 +08:00

PDF Signature Extraction System

Automated extraction of handwritten Chinese signatures from PDF documents using hybrid VLM + Computer Vision approach.

Quick Start

Step 1: Extract Pages from CSV

cd /Volumes/NV2/pdf_recognize
source venv/bin/activate
python extract_pages_from_csv.py

Step 2: Extract Signatures

python extract_signatures_hybrid.py

Documentation

Current Performance

Test Dataset: 5 PDF pages

  • Signatures expected: 10
  • Signatures found: 7
  • Precision: 100% (no false positives)
  • Recall: 70%

Key Features

Hybrid Approach: VLM name extraction + CV detection + VLM verification Name-Based: Signatures saved as signature_周寶蓮.png No False Positives: Name-specific verification filters out dates, text, stamps Duplicate Prevention: Only one signature per person Handles Both: PDFs with/without text layer

File Structure

extract_pages_from_csv.py          # Step 1: Extract pages
extract_signatures_hybrid.py       # Step 2: Extract signatures (CURRENT)
README.md                          # This file
PROJECT_DOCUMENTATION.md           # Complete documentation
README_page_extraction.md          # Page extraction guide
README_hybrid_extraction.md        # Signature extraction guide

Requirements

Data

  • Input: /Volumes/NV2/PDF-Processing/master_signatures.csv (86,073 rows)
  • PDFs: /Volumes/NV2/PDF-Processing/total-pdf/batch_*/
  • Output: /Volumes/NV2/PDF-Processing/signature-image-output/

Status

Page extraction: Tested with 100 files, working Signature extraction: Tested with 5 files, 70% recall, 100% precision Large-scale testing: Pending Full dataset (86K files): Pending

See PROJECT_DOCUMENTATION.md for complete details.

S
Description
Automated extraction of handwritten Chinese signatures from PDF documents using hybrid VLM + Computer Vision approach. 70% recall, 100% precision.
Readme 6.9 MiB
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Python 100%