======================================================================
SOURCE FILE:     ex15_approval_yes_no.yaml
TABULATED FILE:  ex15_approval_yes_no_tabulated.txt
======================================================================

election_title: Exercise 15a — a Yes/No profile (which method is this?)

scenario_description: |-
  Part (a) of Exercise 15 — "Read the ballot, name the method."

  35 voters, three candidates, and a ballot that records only Yes or No per
  candidate — no ranking, no scores, and voters approve different NUMBERS of
  candidates. That combination identifies the method: this is APPROVAL VOTING.
  Blair wins with 28 approvals of 35 ballots (80%), ahead of Cosmo 22 and
  Ada 15.

  Note the shares add to well over 100% — approval percentages are shares of
  BALLOTS, not of a divided pie, and that is the tell most readers miss.

  A textbook-style prompt (a Yes/No table with weighted voter blocs), rebuilt
  here with named candidates so the columns line up A/B/C -> Ada/Blair/Cosmo.
  Companion file ex15_approval_pairwise.yaml re-reads these same ballots
  pairwise; part (b) is ex15_score_profile.yaml.

  Exercise page: ../ex15_read_the_ballot.md
  Live results: https://bettervoting.com/d4v2dh/results (BV2258, race 1 of 2 —
  BetterVoting's own Approval count agrees: Blair.)

bv_test_id: BV2258
bv_election_id: d4v2dh
bv_results_url: https://bettervoting.com/d4v2dh/results

voting_method: Approval
num_winners: 1

ballots: |-
  Count:Ada,Blair,Cosmo
  15:0,1,1
  8:1,1,0
  7:1,0,1
  5:0,1,0

expected_winners:
  - Blair

# file: ex15_approval_yes_no.yaml

======================================================================
TABULATION RESULTS
======================================================================

--- Approval Voting (single winner) ---
 Tabulating 35 ballots (any non-zero score = approval).

Ballots:
   columns = Ada, Blair, Cosmo      (1 = approve; 0 = not approved)
    15 × 0,1,1
     8 × 1,1,0
     7 × 1,0,1
     5 × 0,1,0

   Blair -- 28 (80%) -- Elected
   Cosmo -- 22 (63%)
   Ada   -- 15 (43%)

[Approval Distribution] (how many candidates each ballot approved)
   65 approvals across 35 ballots — average 1.9 of 3 (range 1–2).
     approved 1: 5 ballots
     approved 2: 30 ballots

[Co-Approval Matrix]
 Of the voters who approved the ROW candidate, the % who ALSO approved the COLUMN candidate.
          | Blair  | Cosmo  |  Ada   |
   -----------------------------------
   Blair  |   --   |  54%   |  29%   |
   Cosmo  |  68%   |   --   |  32%   |
   Ada    |  53%   |  47%   |   --   |

Winner — Approval Voting (single winner)
  Blair