计算扑克线下保险的真实期望值

poker_offline_insurance_actual_ev.py

#!/usr/bin/env python3

# Iterate folded cards in [0, 14] from undealt_cards then calculate the actual EV.
def calculate_ev_for_unseen_cards(undealt_cards, outs):
    ev_sum = 0
    count = 0

    for folded_cards in range(0, 15):
        actual_undealt_cards = undealt_cards - folded_cards
        # actual_undealt_cards must be a positive number in real life.
        if actual_undealt_cards > 0:
            # let the actual_outs be a float number, this will lead to the same
            # result as simulating large enough amounts of integer actual_outs then
            # combining their EV sum.
            actual_outs = outs - folded_cards * (outs / undealt_cards)
            actual_odds = actual_outs / actual_undealt_cards
            ev_sum += actual_odds
            count += 1

    return ev_sum / count if count > 0 else outs / undealt_cards

def run_simulation(insurance_cost = 0.05):
    sum_cost_ev = 0
    sum_actual_ev = 0

    # Iterate undealt cards in [1, 42].
    for undealt_cards in range(1, 43):
        # Iterate outs in [0, undealt_cards].
        for outs in range(0, undealt_cards + 1):
            cost_ev = outs / undealt_cards * insurance_cost
            actual_ev = calculate_ev_for_unseen_cards(undealt_cards, outs)
            sum_cost_ev += cost_ev
            sum_actual_ev += actual_ev

    return sum_cost_ev / sum_actual_ev

average_ev_ratio = run_simulation()
print(f"线下保险的真实期望值比例: {average_ev_ratio:.04f}")

#################################################################
# 线下保险的真实期望值比例: 0.0500