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Question 145: Conditional Laws Are Defined Only on Positive-Mass Statistic Cells

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  1. Original question and givens
  2. Definition and scope
  3. Step-by-step derivation
  4. Reverse checks
  5. Result
  6. This question review and source binding

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P250-0145 · q-20261015-advance-20261116-r05-finite-sufficient-statistic-0045

Original question and givens

Use complete theta labels=[a19, b19], samples=[190, 191, 192, 193], aligned exact probability rows=[[[2, 5], [1, 10], [2, 5], [1, 10]], [[1, 10], [2, 5], [1, 10], [2, 5]]] and total statistic=[0, 1, 0, 1]. Each theta law is normalized. Fibers partition the full sample carrier, retaining zero-mass cells. Give (conditional_cells, boundary).

  • G001 — Use complete theta labels=[a19, b19], samples=[190, 191, 192, 193], aligned exact probability rows=[[[2, 5], [1, 10], [2, 5], [1, 10]], [[1, 10], [2, 5], [1, 10], [2, 5]]] and total statistic=[0, 1, 0, 1]. Each theta law is normalized. Fibers partition the full sample carrier, retaining zero-mass cells. Give (conditional_cells, boundary).

Definition and scope

The statistic is total on the full sample carrier. Normalize each parameter law and condition only on positive-mass fibers.

Step-by-step derivation

S001 · implies

Before

Ω=[190, 191, 192, 193]; T=[0, 1, 0, 1]

After

fibers=[[0, [190, 192]], [1, [191, 193]]]

Conditions: none

Group the original sample labels by statistic value; distinguish a sample's position from its label.

Step identifiers and dependencies

Rule: statistic_fibers · Uses: G001

S002 · implies

Before

[[0, [190, 192]], [1, [191, 193]]]

After

disjoint union of fibers = [190, 191, 192, 193]

Conditions: none

Each sample lies in exactly one fiber, and their union covers all of Omega.

Step identifiers and dependencies

Rule: partition_audit · Uses: G001, S001

S003 · calculation

Before

P_a19(Ω) := sum(2/5, 1/10, 2/5, 1/10)

After

P_a19(Ω) = 1

Conditions: none

Verify normalization of the probability row for this parameter.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S002

S004 · calculation

Before

P_a19(T=0) := sum(2/5, 2/5)

After

P_a19(T=0) = 4/5

Conditions: none

Sum only the masses in fiber [190, 192].

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S003

S005 · calculation

Before

P_a19(X=190|T=0) := div(2/5, 4/5)

After

P_a19(X=190|T=0) = 1/2

Conditions: none

The numerator is the atom mass 2/5 under the same law and the denominator is the fiber mass 4/5.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S004

S006 · calculation

Before

reconstruct P_a19(X=190) := mul(1/2, 4/5)

After

reconstruct P_a19(X=190) = 2/5

Conditions: none

Multiply by the fiber mass to recover that atom's original probability.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S005

S007 · calculation

Before

P_a19(X=192|T=0) := div(2/5, 4/5)

After

P_a19(X=192|T=0) = 1/2

Conditions: none

The numerator is the atom mass 2/5 under the same law and the denominator is the fiber mass 4/5.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S006

S008 · calculation

Before

reconstruct P_a19(X=192) := mul(1/2, 4/5)

After

reconstruct P_a19(X=192) = 2/5

Conditions: none

Multiply by the fiber mass to recover that atom's original probability.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S007

S009 · calculation

Before

conditional total (a19,0) := sum(1/2, 1/2)

After

conditional total (a19,0) = 1

Conditions: none

The full conditional law on a positive-mass fiber must sum to 1.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S008

S010 · calculation

Before

P_a19(T=1) := sum(1/10, 1/10)

After

P_a19(T=1) = 1/5

Conditions: none

Sum only the masses in fiber [191, 193].

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S009

S011 · calculation

Before

P_a19(X=191|T=1) := div(1/10, 1/5)

After

P_a19(X=191|T=1) = 1/2

Conditions: none

The numerator is the atom mass 1/10 under the same law and the denominator is the fiber mass 1/5.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S010

S012 · calculation

Before

reconstruct P_a19(X=191) := mul(1/2, 1/5)

After

reconstruct P_a19(X=191) = 1/10

Conditions: none

Multiply by the fiber mass to recover that atom's original probability.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S011

S013 · calculation

Before

P_a19(X=193|T=1) := div(1/10, 1/5)

After

P_a19(X=193|T=1) = 1/2

Conditions: none

The numerator is the atom mass 1/10 under the same law and the denominator is the fiber mass 1/5.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S012

S014 · calculation

Before

reconstruct P_a19(X=193) := mul(1/2, 1/5)

After

reconstruct P_a19(X=193) = 1/10

Conditions: none

Multiply by the fiber mass to recover that atom's original probability.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S013

S015 · calculation

Before

conditional total (a19,1) := sum(1/2, 1/2)

After

conditional total (a19,1) = 1

Conditions: none

The full conditional law on a positive-mass fiber must sum to 1.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S014

S016 · calculation

Before

P_b19(Ω) := sum(1/10, 2/5, 1/10, 2/5)

After

P_b19(Ω) = 1

Conditions: none

Verify normalization of the probability row for this parameter.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S015

S017 · calculation

Before

P_b19(T=0) := sum(1/10, 1/10)

After

P_b19(T=0) = 1/5

Conditions: none

Sum only the masses in fiber [190, 192].

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S016

S018 · calculation

Before

P_b19(X=190|T=0) := div(1/10, 1/5)

After

P_b19(X=190|T=0) = 1/2

Conditions: none

The numerator is the atom mass 1/10 under the same law and the denominator is the fiber mass 1/5.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S017

S019 · calculation

Before

reconstruct P_b19(X=190) := mul(1/2, 1/5)

After

reconstruct P_b19(X=190) = 1/10

Conditions: none

Multiply by the fiber mass to recover that atom's original probability.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S018

S020 · calculation

Before

P_b19(X=192|T=0) := div(1/10, 1/5)

After

P_b19(X=192|T=0) = 1/2

Conditions: none

The numerator is the atom mass 1/10 under the same law and the denominator is the fiber mass 1/5.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S019

S021 · calculation

Before

reconstruct P_b19(X=192) := mul(1/2, 1/5)

After

reconstruct P_b19(X=192) = 1/10

Conditions: none

Multiply by the fiber mass to recover that atom's original probability.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S020

S022 · calculation

Before

conditional total (b19,0) := sum(1/2, 1/2)

After

conditional total (b19,0) = 1

Conditions: none

The full conditional law on a positive-mass fiber must sum to 1.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S021

S023 · calculation

Before

P_b19(T=1) := sum(2/5, 2/5)

After

P_b19(T=1) = 4/5

Conditions: none

Sum only the masses in fiber [191, 193].

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S022

S024 · calculation

Before

P_b19(X=191|T=1) := div(2/5, 4/5)

After

P_b19(X=191|T=1) = 1/2

Conditions: none

The numerator is the atom mass 2/5 under the same law and the denominator is the fiber mass 4/5.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S023

S025 · calculation

Before

reconstruct P_b19(X=191) := mul(1/2, 4/5)

After

reconstruct P_b19(X=191) = 2/5

Conditions: none

Multiply by the fiber mass to recover that atom's original probability.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S024

S026 · calculation

Before

P_b19(X=193|T=1) := div(2/5, 4/5)

After

P_b19(X=193|T=1) = 1/2

Conditions: none

The numerator is the atom mass 2/5 under the same law and the denominator is the fiber mass 4/5.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S025

S027 · calculation

Before

reconstruct P_b19(X=193) := mul(1/2, 4/5)

After

reconstruct P_b19(X=193) = 2/5

Conditions: none

Multiply by the fiber mass to recover that atom's original probability.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S026

S028 · calculation

Before

conditional total (b19,1) := sum(1/2, 1/2)

After

conditional total (b19,1) = 1

Conditions: none

The full conditional law on a positive-mass fiber must sum to 1.

Step identifiers and dependencies

Rule: exact_rational_arithmetic · Uses: G001, S027

S029 · implies

Before

all parameter × fiber cells audited

After

[[a19, 0, 4/5, [[190, 1/2], [192, 1/2]]], [a19, 1, 1/5, [[191, 1/2], [193, 1/2]]], [b19, 0, 1/5, [[190, 1/2], [192, 1/2]]], [b19, 1, 4/5, [[191, 1/2], [193, 1/2]]]]

Conditions: none

Return every cell in parameter order and then statistic-value order; retain the zero-mass branch rule.

Step identifiers and dependencies

Rule: complete_conditional_table · Uses: G001, S028

Reverse checks

  • S029 · premise_and_result_audit — This task computes the conditional table; it makes no estimator-quality claim and does not invoke factorization.
  • S028 · premise_and_result_audit — Recompute conditional total (b19,1) with exact rational arithmetic, not rounded decimals.
  • S027 · premise_and_result_audit — Recompute reconstruct P_b19(X=193) with exact rational arithmetic, not rounded decimals.
  • S026 · premise_and_result_audit — Recompute P_b19(X=193|T=1) with exact rational arithmetic, not rounded decimals.
  • S025 · premise_and_result_audit — Recompute reconstruct P_b19(X=191) with exact rational arithmetic, not rounded decimals.
  • S024 · premise_and_result_audit — Recompute P_b19(X=191|T=1) with exact rational arithmetic, not rounded decimals.
  • S023 · premise_and_result_audit — Recompute P_b19(T=1) with exact rational arithmetic, not rounded decimals.
  • S022 · premise_and_result_audit — Recompute conditional total (b19,0) with exact rational arithmetic, not rounded decimals.
  • S021 · premise_and_result_audit — Recompute reconstruct P_b19(X=192) with exact rational arithmetic, not rounded decimals.
  • S020 · premise_and_result_audit — Recompute P_b19(X=192|T=0) with exact rational arithmetic, not rounded decimals.
  • S019 · premise_and_result_audit — Recompute reconstruct P_b19(X=190) with exact rational arithmetic, not rounded decimals.
  • S018 · premise_and_result_audit — Recompute P_b19(X=190|T=0) with exact rational arithmetic, not rounded decimals.
  • S017 · premise_and_result_audit — Recompute P_b19(T=0) with exact rational arithmetic, not rounded decimals.
  • S016 · premise_and_result_audit — Recompute P_b19(Ω) with exact rational arithmetic, not rounded decimals.
  • S015 · premise_and_result_audit — Recompute conditional total (a19,1) with exact rational arithmetic, not rounded decimals.
  • S014 · premise_and_result_audit — Recompute reconstruct P_a19(X=193) with exact rational arithmetic, not rounded decimals.
  • S013 · premise_and_result_audit — Recompute P_a19(X=193|T=1) with exact rational arithmetic, not rounded decimals.
  • S012 · premise_and_result_audit — Recompute reconstruct P_a19(X=191) with exact rational arithmetic, not rounded decimals.
  • S011 · premise_and_result_audit — Recompute P_a19(X=191|T=1) with exact rational arithmetic, not rounded decimals.
  • S010 · premise_and_result_audit — Recompute P_a19(T=1) with exact rational arithmetic, not rounded decimals.
  • S009 · premise_and_result_audit — Recompute conditional total (a19,0) with exact rational arithmetic, not rounded decimals.
  • S008 · premise_and_result_audit — Recompute reconstruct P_a19(X=192) with exact rational arithmetic, not rounded decimals.
  • S007 · premise_and_result_audit — Recompute P_a19(X=192|T=0) with exact rational arithmetic, not rounded decimals.
  • S006 · premise_and_result_audit — Recompute reconstruct P_a19(X=190) with exact rational arithmetic, not rounded decimals.
  • S005 · premise_and_result_audit — Recompute P_a19(X=190|T=0) with exact rational arithmetic, not rounded decimals.
  • S004 · premise_and_result_audit — Recompute P_a19(T=0) with exact rational arithmetic, not rounded decimals.
  • S003 · premise_and_result_audit — Recompute P_a19(Ω) with exact rational arithmetic, not rounded decimals.
  • S002 · premise_and_result_audit — A fiber stays in the partition even when it has zero mass under a parameter.
  • S001 · premise_and_result_audit — T must have exactly one value at every sample point.

Result

([[a19, 0, 4/5, [[190, 1/2], [192, 1/2]]], [a19, 1, 1/5, [[191, 1/2], [193, 1/2]]], [b19, 0, 1/5, [[190, 1/2], [192, 1/2]]], [b19, 1, 4/5, [[191, 1/2], [193, 1/2]]]], zero_mass_cells_remain_undefined)

The full cellwise conditional laws are listed; zero-mass cells must retain null.

This question review and source binding

Review date: 2026-10-24

Original questions, answers, step expressions, numeric ASTs and historical records are retained. Source candidate labels remain historical and are not overwritten as formal proof.

Source hashes and review receipts
  • input commit: 0f7be61e2c22317a4075561dc822c87d881a50db
  • original question SHA-256: ef58ce95eb9c0ffc347863d5f9b76f8ff3cb07d9d3baf2f8ee35d748fcc37c4a
  • candidate record SHA-256: 10316acbfc323c3a5d61a15e4ffdd564621ae2c1cc692c92f3f38fe325b8bac5
  • semantic review receipt SHA-256: 4727d1bd957a9b7f6cadb7972ddb5ab80a31f5259dc5394c1dff2b71944ed36b
  • question-first witness SHA-256: 51e18649133238ac992229f6e16542a5f3af53ca73b2262ab0524508ea937dee
  • Lean: NOT_RUN · human review: NOT_PERFORMED
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