Disposal rate method

[henrydingliu]

Summary of Changes

Related GitHub Issue(s)

Additional Context for Reviewers

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

[github-actions]

Pyright Type Completeness

View the full pyright --verifytypes output for this commit

Project (full chainladder package, at this PR's head): 14.1% of exported symbols fully typed (175 / 1237)

	Known	Ambiguous	Unknown	Total
Project (head)	175	107	955	1237

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: 314
• Functions without default param: 0
• Classes without docstring: 10

Patch (exported symbols added or changed by this PR): 40.0% fully typed (12 / 30)

	Known	Ambiguous	Unknown	Total
Patch	12	0	18	30

Patch symbol details

Symbol	Status	Change
chainladder.adjustments.DisposalRate	❌ unknown	new
chainladder.adjustments.disposal.DisposalMixin	❌ unknown	new
chainladder.adjustments.disposal.DisposalMixin.disposal_rate_	❌ unknown	new
chainladder.adjustments.disposal.DisposalMixin.incr_disposal_rate_	❌ unknown	new
chainladder.adjustments.disposal.DisposalRate	❌ unknown	new
chainladder.adjustments.disposal.DisposalRate.X_	❌ unknown	new
chainladder.adjustments.disposal.DisposalRate.__init__	❌ unknown	new
chainladder.adjustments.disposal.DisposalRate.average	✅ known	new
chainladder.adjustments.disposal.DisposalRate.disposal_rate_	❌ unknown	new
chainladder.adjustments.disposal.DisposalRate.disposal_w_	✅ known	new
chainladder.adjustments.disposal.DisposalRate.drop	❌ unknown	new
chainladder.adjustments.disposal.DisposalRate.drop_above	✅ known	new
chainladder.adjustments.disposal.DisposalRate.drop_below	✅ known	new
chainladder.adjustments.disposal.DisposalRate.drop_high	✅ known	new
chainladder.adjustments.disposal.DisposalRate.drop_low	✅ known	new
chainladder.adjustments.disposal.DisposalRate.drop_valuation	✅ known	new
chainladder.adjustments.disposal.DisposalRate.fit	❌ unknown	new
chainladder.adjustments.disposal.DisposalRate.fit_transform	❌ unknown	new
chainladder.adjustments.disposal.DisposalRate.n_periods	✅ known	new
chainladder.adjustments.disposal.DisposalRate.preserve	✅ known	new
chainladder.adjustments.disposal.DisposalRate.transform	❌ unknown	new
chainladder.adjustments.disposal.DisposalRate.xp	❌ unknown	new
chainladder.adjustments.tests.test_disposal.test_cl_parity	❌ unknown	new
chainladder.adjustments.tests.test_disposal.test_friedland_fidelity	✅ known	new
chainladder.adjustments.tests.test_disposal.test_no_disposal_exception	❌ unknown	new
chainladder.adjustments.tests.test_disposal.test_no_weight_exception	❌ unknown	new
chainladder.adjustments.tests.test_disposal.test_setting_incr	❌ unknown	new
chainladder.adjustments.tests.test_disposal.test_sparse_transform	❌ unknown	new
chainladder.core.triangle.Triangle.disposal_rate_tri	✅ known	new
chainladder.core.triangle.Triangle.is_disposal_rate	✅ known	new