def test_bulk_athena():
# Same as Minerva (that is, delta = infinity)
# Ballot-by-ballot Minerva should yield identical stopping rules to BRAVO.
contest = Contest(100000, {
'A': 60000,
'B': 40000
}, 1, ['A'], ContestType.MAJORITY)
athena = Athena(.1, 2**31 - 1, .01, contest)
athena.compute_all_min_winner_ballots(athena.sub_audits['A-B'])
# p0 not hardcoded as .5 for scalability with odd total contest ballots.
p0 = (athena.contest.contest_ballots // 2) / athena.contest.contest_ballots
log_winner_multiplier = math.log(
athena.sub_audits['A-B'].sub_contest.winner_prop / p0)
log_loser_multiplier = math.log(
(1 - athena.sub_audits['A-B'].sub_contest.winner_prop) / p0)
log_rhs = math.log(1 / athena.alpha)
for i in range(len(athena.rounds)):
n = athena.rounds[i]
kmin = athena.sub_audits['A-B'].min_winner_ballots[i]
# Assert this kmin satisfies ratio, but a kmin one less does not.
assert kmin * log_winner_multiplier + (
n - kmin) * log_loser_multiplier > log_rhs
assert (kmin - 1) * log_winner_multiplier + (
n - kmin + 1) * log_loser_multiplier <= log_rhs
def test_exceptions():
contest = Contest(100000, {
'A': 60000,
'B': 40000
}, 1, ['A'], ContestType.MAJORITY)
with pytest.raises(ValueError):
Athena(.1, 0, .1, contest)
athena = Athena(.1, 1, .1, contest)
with pytest.raises(Exception):
athena.stopping_condition_pairwise('A-B')
athena.rounds.append(10)
with pytest.raises(ValueError):
athena.stopping_condition_pairwise('X')
athena.rounds = []
with pytest.raises(ValueError):
athena.compute_min_winner_ballots(athena.sub_audits['A-B'], [])
with pytest.raises(ValueError):
athena.compute_min_winner_ballots(athena.sub_audits['A-B'], [0])
with pytest.raises(ValueError):
athena.compute_min_winner_ballots(athena.sub_audits['A-B'], [1, 2])
with pytest.raises(ValueError):
athena.compute_min_winner_ballots(athena.sub_audits['A-B'], [20, 20])
with pytest.raises(ValueError):
athena.compute_min_winner_ballots(athena.sub_audits['A-B'], [20, 19])
with pytest.raises(ValueError):
athena.compute_min_winner_ballots(athena.sub_audits['A-B'], [10001])
athena.compute_min_winner_ballots(athena.sub_audits['A-B'], [20])
with pytest.raises(ValueError):
athena.compute_min_winner_ballots(athena.sub_audits['A-B'], [20])
with pytest.raises(ValueError):
athena.compute_min_winner_ballots(athena.sub_audits['A-B'], [19])
with pytest.raises(ValueError):
athena.compute_min_winner_ballots(athena.sub_audits['A-B'], [10001])
contest2 = Contest(100, {'A': 60, 'B': 30}, 1, ['A'], ContestType.MAJORITY)
athena2 = Athena(0.1, 1, 1.0, contest2)
with pytest.raises(ValueError):
athena2.compute_min_winner_ballots(athena2.sub_audits['A-B'], [91])
athena2.rounds.append(10)
with pytest.raises(Exception):
athena2.compute_all_min_winner_ballots(athena2.sub_audits['A-B'])
athena2.rounds = []
with pytest.raises(ValueError):
athena2.compute_all_min_winner_ballots(athena2.sub_audits['A-B'], 0)
with pytest.raises(ValueError):
athena2.compute_all_min_winner_ballots(athena2.sub_audits['A-B'], 200)
with pytest.raises(ValueError):
athena2.compute_all_min_winner_ballots(athena2.sub_audits['A-B'], 0)