Question 14124: Preserve Every Selected Conditioning-Block Integral

Original question and givens

Use one complete finite probability space with outcome indices 0 through 3, aligned masses=[6/49, 15/49, 8/49, 20/49], values X=[11, -1, 25, -11], and conditioning-block labels=[0, 0, 1, 1]. Masses are nonnegative and total exactly 1. Block labels describe a partition of this same space; list block summaries in increasing label order and outcomes in original index order. Conditional expectation is constant on each positive-mass block, with its weighted mean, and preserves every block integral. A zero-mass block is only determined almost surely: return a.s._arbitrary, never divide by zero. Use exact reduced fractions with positive denominators, omitting /1 for integers. Selected block_label=1 must exist. Give (block_label,indices,original_integral,conditional_integral,equal?,boundary). Boundary is positive_block or null_block_a.s._arbitrary.

• G001 — Use one complete finite probability space with outcome indices 0 through 3, aligned masses=[6/49, 15/49, 8/49, 20/49], values X=[11, -1, 25, -11], and conditioning-block labels=[0, 0, 1, 1]. Masses are nonnegative and total exactly 1. Block labels describe a partition of this same space; list block summaries in increasing label order and outcomes in original index order. Conditional expectation is constant on each positive-mass block, with its weighted mean, and preserves every block integral. A zero-mass block is only determined almost surely: return a.s._arbitrary, never divide by zero. Use exact reduced fractions with positive denominators, omitting /1 for integers. Selected block_label=1 must exist. Give (block_label,indices,original_integral,conditional_integral,equal?,boundary). Boundary is positive_block or null_block_a.s._arbitrary.

Definition and scope

Use the original question domain, assumptions and cited MKO definitions. This item has second-context mathematical and bilingual review, with the model, answer and every arithmetic step independently recomputed from the original parameters; the source question remains a candidate.

• mko-conditional-expectation

Step-by-step derivation

conditional model whole mass sum := sum(6/49, 15/49, 8/49, 20/49)

conditional model whole mass sum = 1

conditional model:raw aligned masses=[[6, 49], [15, 49], [8, 49], [20, 49]]

normalized masses=[6/49, 15/49, 8/49, 20/49];nonnegative=Yes;total=1

same outcome indices=[0, 1, 2, 3];X values=[11, -1, 25, -11];block labels=[0, 0, 1, 1]

distinct conditioning labels in increasing order=[0, 1]

block0 mass := sum(6/49, 15/49)

block0 mass = 3/7

block0 atom0 weighted X := mul(6/49, 11)

block0 atom0 weighted X = 66/49

block0 atom1 weighted X := mul(15/49, -1)

block0 atom1 weighted X = -15/49

block0 original weighted integral := sum(66/49, -15/49)

block0 original weighted integral = 51/49

block0 positive-mass conditional mean := div(51/49, 3/7)

block0 positive-mass conditional mean = 17/7

block label=0;indices=[0, 1];positive mass=3/7;weighted integral=51/49

block-constant conditional value=17/7

block1 mass := sum(8/49, 20/49)

block1 mass = 4/7

block1 atom2 weighted X := mul(8/49, 25)

block1 atom2 weighted X = 200/49

block1 atom3 weighted X := mul(20/49, -11)

block1 atom3 weighted X = -220/49

block1 original weighted integral := sum(200/49, -220/49)

block1 original weighted integral = -20/49

block1 positive-mass conditional mean := div(-20/49, 4/7)

block1 positive-mass conditional mean = -5/7

block label=1;indices=[2, 3];positive mass=4/7;weighted integral=-20/49

block-constant conditional value=-5/7

selected block block1 conditional integral := mul(4/7, -5/7)

selected block block1 conditional integral = -20/49

selected block=1;indices=[2, 3];original integral=-20/49;conditional integral=-20/49

equal=Yes;this is the selected block obligation,not only a global average

Reverse checks

• S017 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.
• S016 · premise_and_result_audit — Recompute selected block block1 conditional integral with exact rational arithmetic, not rounded decimals.
• S015 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.
• S014 · premise_and_result_audit — Recompute block1 positive-mass conditional mean with exact rational arithmetic, not rounded decimals.
• S013 · premise_and_result_audit — Recompute block1 original weighted integral with exact rational arithmetic, not rounded decimals.
• S012 · premise_and_result_audit — Recompute block1 atom3 weighted X with exact rational arithmetic, not rounded decimals.
• S011 · premise_and_result_audit — Recompute block1 atom2 weighted X with exact rational arithmetic, not rounded decimals.
• S010 · premise_and_result_audit — Recompute block1 mass with exact rational arithmetic, not rounded decimals.
• S009 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.
• S008 · premise_and_result_audit — Recompute block0 positive-mass conditional mean with exact rational arithmetic, not rounded decimals.
• S007 · premise_and_result_audit — Recompute block0 original weighted integral with exact rational arithmetic, not rounded decimals.
• S006 · premise_and_result_audit — Recompute block0 atom1 weighted X with exact rational arithmetic, not rounded decimals.
• S005 · premise_and_result_audit — Recompute block0 atom0 weighted X with exact rational arithmetic, not rounded decimals.
• S004 · premise_and_result_audit — Recompute block0 mass with exact rational arithmetic, not rounded decimals.
• S003 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.
• S002 · premise_and_result_audit — Check against the original data and this step's premises; a one-way implication is not an equivalence.
• S001 · premise_and_result_audit — Recompute conditional model whole mass sum with exact rational arithmetic, not rounded decimals.

Result

(1, [2, 3], -20/49, -20/49, Yes, positive_block)

The full substitutions and premise checks give the original answer; source identity,format and status are unchanged.

This question review and source binding

Review date: 2026-10-26

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