mmr.py

# SPDX-License-Identifier: AGPL-3.0-only
# Copyright (C) 2021 Sean Anderson <seanga2@gmail.com>

import collections
import sqlite3

from math import exp, pi, sqrt

mu_0 = 0
sigma2_0 = 1
beta2 = 2 * (sqrt(sigma2_0) / 2) ** 2
kappa = 0.00001

# Algorithm 1 from Weng 2011
# Note that delta/eta are missing a factor of sigma2_i, since it is immediately divided out when
# calculating mu_ij/sigma2_ij
def bt(players, s, steamids_i, steamids_q):
    mu_i = sum(players[steamid][0] for steamid in steamids_i)
    mu_q = sum(players[steamid][0] for steamid in steamids_q)
    sigma2_i = sum(players[steamid][1] for steamid in steamids_i)
    sigma2_q = sum(players[steamid][1] for steamid in steamids_q)

    c_iq = sqrt(sigma2_i + sigma2_q + beta2)
    v_i = exp(mu_i / c_iq)
    v_q = exp(mu_q / c_iq)
    p_iq = v_i / (v_i + v_q)
    p_qi = v_q / (v_i + v_q)
    delta_q = (s - p_iq) / c_iq
    delta_i = (s - p_qi) / c_iq
    gamma_q = sqrt(sigma2_i) / c_iq
    gamma_i = sqrt(sigma2_q) / c_iq
    eta_common = p_iq * p_qi / c_iq / c_iq
    eta_q = gamma_q * eta_common
    eta_i = gamma_i * eta_common

    for steamid in steamids_i:
        mu, sigma2 = players[steamid]
        mu += players[steamid][1] * delta_q
        sigma2 *= max(1 - players[steamid][1] * eta_q, kappa)
        players[steamid] = mu, sigma2

    for steamid in steamids_q:
        mu, sigma2 = players[steamid]
        mu += players[steamid][1] * delta_i
        sigma2 *= max(1 - players[steamid][1] * eta_i, kappa)
        players[steamid] = mu, sigma2


def main():
    players = collections.defaultdict(lambda: (mu_0, sigma2_0))

    c = sqlite3.connect("23.sqlite3")
    logs = c.execute("""SELECT
                            CASE WHEN red_score > blu_score THEN 1 WHEN red_score < blu_score THEN 0 ELSE 0.5 END AS s,
                            group_concat(CASE WHEN team = 'Red' THEN steam_id END) AS red_players,
                            group_concat(CASE WHEN team = 'Blue' THEN steam_id END) AS blue_players
                        FROM log
                        JOIN player ON (id = log_id)
                        WHERE id < 2390000
                        GROUP BY id
                        ORDER BY id ASC;""")
    for log in logs:
        if not log[1] or not log[2]:
            continue
        steamids_i = [int(player) for player in log[1].split(',')]
        steamids_q = [int(player) for player in log[2].split(',')]
        bt(players, log[0], steamids_i, steamids_q)

    ties = 0
    correct = 0
    incorrect = 0
    logs = c.execute("""SELECT
                            CASE WHEN red_score > blu_score THEN 1 WHEN red_score < blu_score THEN 0 ELSE 0.5 END AS s,
                            group_concat(CASE WHEN team = 'Red' THEN steam_id END) AS red_players,
                            group_concat(CASE WHEN team = 'Blue' THEN steam_id END) AS blue_players,
                            id
                        FROM log
                        JOIN player ON (id = log_id)
                        WHERE id > 2390000
                        GROUP BY id
                        ORDER BY id ASC;""")
    for log in logs:
        if not log[1] or not log[2]:
            continue
        steamids_i = [int(player) for player in log[1].split(',')]
        steamids_q = [int(player) for player in log[2].split(',')]
        mu_i = sum(players[steamid][0] for steamid in steamids_i)
        mu_q = sum(players[steamid][0] for steamid in steamids_q)
        if log[0] == 0.5:
            ties +=1
        elif (mu_i > mu_q and log[0]) or (mu_i < mu_q and not log[0]):
            correct += 1
        else:
            incorrect += 1
    print(correct, incorrect, ties)

    c.execute("BEGIN;")
    c.execute("DROP TABLE IF EXISTS mmr;")
    c.execute("CREATE TABLE mmr (steam_id INTEGER PRIMARY KEY, mu REAL, sigma2 REAL)")
    c.executemany("INSERT INTO mmr (steam_id, mu, sigma2) VALUES (?, ?, ?);",
                  ((steamid, player[0], player[1]) for (steamid, player) in players.items()))
    c.execute("COMMIT;")

if __name__ == '__main__':
    main()