base rate:
NYC mayors rarely pass major corporate tax increases in their first year. NYC's Business Corporation Tax is partially state-governed. NY State corporate tax rate changes are infrequent — last major change was the temporary COVID-era surcharge on large corporations in 2021. The base rate for a new mayor achieving a corporate tax increase within 12 months of taking office is probably under 10%.
evidence updates:
Mamdani winning (confirmed) removes one major uncertainty. His democratic socialist ideology pushes UP the probability he'll try. But no evidence of formal proposals being introduced pushes DOWN. The 'still being negotiated' status of state budget proposals is ambiguous — could mean something is moving, or could mean nothing concrete exists. The time constraint (8.5 months) is severe for legislative action. The broad resolution criteria (NYC OR NY State) pushes UP slightly.
combination method:
Conditional chain: P(wins) × P(proposes | wins) × P(passes | proposed) + small independent probability of NY State acting on corporate taxes regardless. 0.98 × 0.55 × 0.18 ≈ 0.097, plus ~0.03 for independent state action = ~0.12.
final:
Despite Mamdani being in office with strong progressive motivation, the structural barriers to passing corporate tax legislation in NYC (which requires state cooperation) within less than a year are substantial. No evidence of concrete legislative progress significantly dampens the probability. The ongoing state budget negotiations provide a pathway but passage is far from certain. Final estimate: 12%.
ensemble:
{'ensemble_count': 3, 'perspectives': {'base_rate': {'p_yes': 0.12, 'confidence': 0.45}, 'evidence_driven': {'p_yes': 0.14, 'confidence': 0.45}, 'contrarian': {'p_yes': 0.15, 'confidence': 0.5}}, 'spread': 0.03, 'individual_p_yes': {'base_rate': 0.12, 'evidence_driven': 0.14, 'contrarian': 0.15}}