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552b6b80d4a0dbe8f285cae476e8e7aca11ba64e
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Author SHA1 Message Date
gbanyan 552b6b80d4 Paper A v3.7: demote BD/McCrary to density-smoothness diagnostic; add Appendix A 
Implements codex gpt-5.4 recommendation (paper/codex_bd_mccrary_opinion.md,
"option (c) hybrid"): demote BD/McCrary in the main text from a co-equal
threshold estimator to a density-smoothness diagnostic, and add a
bin-width sensitivity appendix as an audit trail.

Why: the bin-width sweep (Script 25) confirms that at the signature
level the BD transition drifts monotonically with bin width (Firm A
cosine: 0.987 -> 0.985 -> 0.980 -> 0.975 as bin width widens 0.003 ->
0.015; full-sample dHash transitions drift from 2 to 10 to 9 across
bin widths 1 / 2 / 3) and Z statistics inflate superlinearly with bin
width, both characteristic of a histogram-resolution artifact. At the
accountant level the BD null is robust across the sweep. The paper's
earlier "three methodologically distinct estimators" framing therefore
could not be defended to an IEEE Access reviewer once the sweep was
run.

Added
- signature_analysis/25_bd_mccrary_sensitivity.py: bin-width sweep
  across 6 variants (Firm A / full-sample / accountant-level, each
  cosine + dHash_indep) and 3-4 bin widths per variant. Reports
  Z_below, Z_above, p-values, and number of significant transitions
  per cell. Writes reports/bd_sensitivity/bd_sensitivity.{json,md}.
- paper/paper_a_appendix_v3.md: new "Appendix A. BD/McCrary Bin-Width
  Sensitivity" with Table A.I (all 20 sensitivity cells) and
  interpretation linking the empirical pattern to the main-text
  framing decision.
- export_v3.py: appendix inserted into SECTIONS between conclusion
  and references.
- paper/codex_bd_mccrary_opinion.md: codex gpt-5.4 recommendation
  captured verbatim for audit trail.

Main-text reframing
- Abstract: "three methodologically distinct estimators" ->
  "two estimators plus a Burgstahler-Dichev/McCrary density-
  smoothness diagnostic". Trimmed to 243 words.
- Introduction: related-work summary, pipeline step 5, accountant-
  level convergence sentence, contribution 4, and section-outline
  line all updated. Contribution 4 renamed to "Convergent threshold
  framework with a smoothness diagnostic".
- Methodology III-I: section renamed to "Convergent Threshold
  Determination with a Density-Smoothness Diagnostic". "Method 2:
  BD/McCrary Discontinuity" converted to "Density-Smoothness
  Diagnostic" in a new subsection; Method 3 (Beta mixture) renumbered
  to Method 2. Subsections 4 and 5 updated to refer to "two threshold
  estimators" with BD as diagnostic.
- Methodology III-A pipeline overview: "three methodologically
  distinct statistical methods" -> "two methodologically distinct
  threshold estimators complemented by a density-smoothness
  diagnostic".
- Methodology III-L: "three-method analysis" -> "accountant-level
  threshold analysis (KDE antimode, Beta-2 crossing, logit-Gaussian
  robustness crossing)".
- Results IV-D.1 heading: "BD/McCrary Discontinuity" ->
  "BD/McCrary Density-Smoothness Diagnostic". Prose now notes the
  Appendix-A bin-width instability explicitly.
- Results IV-E: Table VIII restructured to label BD rows
  "(diagnostic only; bin-unstable)" and "(diagnostic; null across
  Appendix A)". Summary sentence rewritten to frame BD null as
  evidence for clustered-but-smoothly-mixed rather than as a
  convergence failure. Table cosine P5 row corrected from 0.941 to
  0.9407 to match III-K.
- Results IV-G.3 and IV-I.2: "three-method convergence/thresholds"
  -> "accountant-level convergent thresholds" (clarifies the 3
  converging estimates are KDE antimode, Beta-2, logit-Gaussian,
  not KDE/BD/Beta).
- Discussion V-B: "three-method framework" -> "convergent threshold
  framework".
- Conclusion: "three methodologically distinct methods" -> "two
  threshold estimators and a density-smoothness diagnostic";
  contribution 3 restated; future-work sentence updated.
- Impact Statement (archived): "three methodologically distinct
  threshold-selection methods" -> "two methodologically distinct
  threshold estimators plus a density-smoothness diagnostic" so the
  archived text is internally consistent if reused.

Discussion V-B / V-G already framed BD as a diagnostic in v3.5
(unchanged in this commit). The reframing therefore brings Abstract /
Introduction / Methodology / Results / Conclusion into alignment with
the Discussion framing that codex had already endorsed.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
 2026-04-21 14:32:50 +08:00
gbanyan 6946baa096 Paper A v3.6: codex round-5 quick-wins cleanup (Minor Revision) 
Codex gpt-5.4 round-5 (codex_review_gpt54_v3_5.md) verdict was Minor
Revision - all v3.4 round-4 PARTIAL/UNFIXED items now confirmed
RESOLVED, including line-by-line recomputation of Table XI z/p
matching the manuscript values. This commit cleans the remaining
quick-win items:

Table IX numerical sync to Script 24 authoritative values
- Five count corrections: cos>0.837 (60,405->60,408), cos>0.945
  (57,131/94.52% -> 56,836/94.02%, was 295 sigs / 0.50 pp off),
  cos>0.973 (48,910/80.91% -> 48,028/79.45%, was 882 sigs / 1.46 pp
  off), cos>0.95 (55,916->55,922), dh<=8 (57,521->57,527),
  dh<=15 (60,345->60,348), dual (54,373->54,370).
- Threshold label cos>0.941 -> cos>0.9407 (use exact calib-fold P5
  rather than rounded value).
- "dHash_indep <= 5 (calib-fold median-adjacent)" relabeled to
  "(whole-sample upper-tail of mode)" to match what III-L explains.
- Added "(operational dual)" / "(style-consistency boundary)" labels
  for unambiguous mapping into III-L category definitions.
- Removed circularity-language footnote inside the table comment.

Circularity overclaim removed paper-wide
- Methodology III-K (Section 3 anchor): "we break the resulting
  circularity" -> "we make the within-Firm-A sampling variance
  visible".
- Results IV-G.2 subsection title: "(breaks calibration-validation
  circularity)" -> "(within-Firm-A sampling variance disclosure)".
- Combined with the v3.5 Abstract / Conclusion edits, no surviving
  use of circular* anywhere in the paper.

export_v3.py title page now single-anonymized
- Removed "[Authors removed for double-blind review]" placeholder
  (IEEE Access uses single-anonymized review).
- Replaced with explicit "[AUTHOR NAMES - fill in before submission]"
  + affiliation placeholder so the requirement is unmissable.
- Subtitle now reads "single-anonymized review".

III-G stale "cosine-conditional dHash" sentence removed
- After the v3.5 III-L rewrite to dh_indep, the sentence at
  Methodology L131 referencing "cosine-conditional dHash used as a
  diagnostic elsewhere" no longer described any current paper usage.
- Replaced with a positive statement that dh_indep is the dHash
  statistic used throughout the operational classifier and all
  reported capture-rate analyses.

Abstract trimmed 247 -> 242 words for IEEE 250-word safety margin
- "an end-to-end pipeline" -> "a pipeline"; "Unlike signature
  forgery" -> "Unlike forgery"; "we report" passive recast; small
  conjunction trims.

Outstanding items deferred (require user decision / larger scope):
- BD/McCrary either substantiate (Z/p table + bin-width robustness)
  or demote to supplementary diagnostic.
- Visual-inspection protocol disclosure (sample size, rater count,
  blinding, adjudication rule).
- Reproducibility appendix (VLM prompt, HSV thresholds, seeds, EM
  init / stopping / boundary handling).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
 2026-04-21 12:41:11 +08:00
gbanyan 12f716ddf1 Paper A v3.5: resolve codex round-4 residual issues 
Fully addresses the partial-resolution / unfixed items from codex
gpt-5.4 round-4 review (codex_review_gpt54_v3_4.md):

Critical
- Table XI z/p columns now reproduce from displayed counts. Earlier
  table had 1-4-unit transcription errors in k values and a fabricated
  cos > 0.9407 calibration row; both fixed by rerunning Script 24
  with cos = 0.9407 added to COS_RULES and copying exact values from
  the JSON output.
- Section III-L classifier now defined entirely in terms of the
  independent-minimum dHash statistic that the deployed code (Scripts
  21, 23, 24) actually uses; the legacy "cosine-conditional dHash"
  language is removed. Tables IX, XI, XII, XVI are now arithmetically
  consistent with the III-L classifier definition.
- "0.95 not calibrated to Firm A" inconsistency reconciled: Section
  III-H now correctly says 0.95 is the whole-sample Firm A P95 of the
  per-signature cosine distribution, matching III-L and IV-F.

Major
- Abstract trimmed to 246 words (from 367) to meet IEEE Access 250-word
  limit. Removed "we break the circularity" overclaim; replaced with
  "report capture rates on both folds with Wilson 95% intervals to
  make fold-level variance visible".
- Conclusion mirrors the Abstract reframe: 70/30 split documents
  within-firm sampling variance, not external generalization.
- Introduction no longer promises precision / F1 / EER metrics that
  Methods/Results don't deliver; replaced with anchor-based capture /
  FAR + Wilson CI language.
- Section III-G within-auditor-year empirical-check wording corrected:
  intra-report consistency (IV-H.3) is a different test (two co-signers
  on the same report, firm-level homogeneity) and is not a within-CPA
  year-level mixing check; the assumption is maintained as a bounded
  identification convention.
- Section III-H "two analyses fully threshold-free" corrected to "only
  the partner-level ranking is threshold-free"; longitudinal-stability
  uses 0.95 cutoff, intra-report uses the operational classifier.

Minor
- Impact Statement removed from export_v3.py SECTIONS list (IEEE Access
  Regular Papers do not have a standalone Impact Statement). The file
  itself is retained as an archived non-paper note for cover-letter /
  grant-report reuse, with a clear archive header.
- All 7 previously unused references ([27] dHash, [31][32] partner-
  signature mandates, [33] Taiwan partner rotation, [34] YOLO original,
  [35] VLM survey, [36] Mann-Whitney) are now cited in-text:
    [27] in Methodology III-E (dHash definition)
    [31][32][33] in Introduction (audit-quality regulation context)
    [34][35] in Methodology III-C/III-D
    [36] in Results IV-C (Mann-Whitney result)

Updated Script 24 to include cos = 0.9407 in COS_RULES so Table XI's
calibration-fold P5 row is computed from the same data file as the
other rows.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
 2026-04-21 12:23:03 +08:00
gbanyan 9b11f03548 Paper A v3: full rewrite for IEEE Access with three-method convergence 
Major changes from v2:

Terminology:
- "digitally replicated" -> "non-hand-signed" throughout (per partner v3
  feedback and to avoid implicit accusation)
- "Firm A near-universal non-hand-signing" -> "replication-dominated"
  (per interview nuance: most but not all Firm A partners use replication)

Target journal: IEEE TAI -> IEEE Access (per NCKU CSIE list)

New methodological sections (III.G-III.L + IV.D-IV.G):
- Three convergent threshold methods (KDE antimode + Hartigan dip test /
  Burgstahler-Dichev McCrary / EM-fitted Beta mixture + logit-GMM
  robustness check)
- Explicit unit-of-analysis discussion (signature vs accountant)
- Accountant-level 2D Gaussian mixture (BIC-best K=3 found empirically)
- Pixel-identity validation anchor (no manual annotation needed)
- Low-similarity negative anchor + Firm A replication-dominated anchor

New empirical findings integrated:
- Firm A signature cosine UNIMODAL (dip p=0.17) - long left tail = minority
  hand-signers
- Full-sample cosine MULTIMODAL but not cleanly bimodal (BIC prefers 3-comp
  mixture) - signature-level is continuous quality spectrum
- Accountant-level mixture trimodal (C1 Deloitte-heavy 139/141,
  C2 other Big-4, C3 smaller firms). 2-comp crossings cos=0.945, dh=8.10
- Pixel-identity anchor (310 pairs) gives perfect recall at all cosine
  thresholds
- Firm A anchor rates: cos>0.95=92.5%, dual-rule cos>0.95 AND dh<=8=89.95%

New discussion section V.B: "Continuous-quality spectrum vs discrete-
behavior regimes" - the core interpretive contribution of v3.

References added: Hartigan & Hartigan 1985, Burgstahler & Dichev 1997,
McCrary 2008, Dempster-Laird-Rubin 1977, White 1982 (refs 37-41).

export_v3.py builds Paper_A_IEEE_Access_Draft_v3.docx (462 KB, +40% vs v2
from expanded methodology + results sections).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
 2026-04-21 00:14:47 +08:00