Chapter 11

[henrydingliu]

Summary of Changes

Related GitHub Issue(s)

Additional Context for Reviewers

Checklist

• I passed tests locally for both code (uv run pytest) and documentation changes (uv run --directory docs jb build . --builder=custom --custom-builder=doctest)

---

Note

Low Risk
Changes are limited to docs, sample data, and display/assert tweaks in the Chapter 11 notebook with no production API changes.

Overview
Updates the Friedland Chapter 11 notebook so exhibit tables match the book’s formatting: format_exh now accepts a date_format argument (default year-only), and half-year auto examples pass {:%Y%m} for accident periods. LDF average tables drop the index name via rename_axis(""), and several Exhibit III sheets route severity/frequency summaries through format_exh instead of ad hoc rounding or transposed raw frames.

The friedland_auto_freq_sev sample CSV is normalized (numbered rows) and one reported-severity cell is corrected (4683 → 4638). Exhibit IV’s on-level Triangle is built with cumulative=True, and one Friedland reconciliation assert switches from absolute to relative tolerance.

^{Reviewed by Cursor Bugbot for commit dd18092. Bugbot is set up for automated code reviews on this repo. Configure here.}

[github-actions]

Pyright Type Completeness

View the full pyright --verifytypes output for this commit

Project (full chainladder package, at this PR's head): 15.0% of exported symbols fully typed (196 / 1308)

	Known	Ambiguous	Unknown	Total
Project (head)	196	111	1001	1308

Other symbols referenced but not exported by chainladder: 13

	Known	Ambiguous	Unknown	Total
Other (head)	3	1	9	13

Symbols without documentation:

• Functions without docstring: 315
• Functions without default param: 0
• Classes without docstring: 10

Patch (exported symbols added or changed by this PR): no exported symbol type-completeness changes detected.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 91.20%. Comparing base (cba3b81) to head (dd18092).
⚠️ Report is 12 commits behind head on chapter_11_parking.

Additional details and impacted files

@@                 Coverage Diff                 @@
##           chapter_11_parking    #1188   +/-   ##
===================================================
  Coverage               91.20%   91.20%           
===================================================
  Files                      91       91           
  Lines                    5380     5380           
  Branches                  683      683           
===================================================
  Hits                     4907     4907           
- Misses                    339      343    +4     
+ Partials                  134      130    -4     

Flag	Coverage Δ
unittests	91.20% <ø> (ø)

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