Files
trueskill-tt/src/game.rs
2022-06-20 23:58:05 +02:00

504 lines
15 KiB
Rust

use crate::{
approx, compute_margin, evidence,
gaussian::Gaussian,
message::{DiffMessage, TeamMessage},
player::Player,
sort_perm, tuple_gt, tuple_max, N00, N_INF,
};
pub struct Game {
teams: Vec<Vec<Player>>,
result: Vec<f64>,
weights: Vec<Vec<f64>>,
p_draw: f64,
pub(crate) likelihoods: Vec<Vec<Gaussian>>,
pub(crate) evidence: f64,
}
impl Game {
pub fn new(
teams: Vec<Vec<Player>>,
mut result: Vec<f64>,
mut weights: Vec<Vec<f64>>,
p_draw: f64,
) -> Self {
assert!(
(result.is_empty() || result.len() == teams.len()),
"result must be empty or the same length as teams"
);
assert!(
(weights.is_empty() || weights.len() == teams.len()),
"weights must be empty or the same length as teams"
);
assert!(
weights.is_empty()
|| weights
.iter()
.zip(teams.iter())
.all(|(w, t)| w.len() == t.len()),
"weights must be empty or has the same dimensions as teams"
);
assert!(
(0.0..1.0).contains(&p_draw),
"draw probability.must be >= 0.0 and < 1.0"
);
assert!(
p_draw > 0.0 || {
let mut r = result.clone();
r.sort_unstable_by(|a, b| a.partial_cmp(b).unwrap());
r.windows(2).all(|w| w[0] != w[1])
},
"draw must be > 0.0 if there is teams with draw"
);
if result.is_empty() {
result = (0..teams.len()).rev().map(|i| i as f64).collect::<Vec<_>>();
}
if weights.is_empty() {
weights = teams
.iter()
.map(|team| vec![1.0; team.len()])
.collect::<Vec<_>>();
}
let mut this = Self {
teams,
result,
weights,
p_draw,
likelihoods: Vec::new(),
evidence: 0.0,
};
this.likelihoods();
this
}
fn likelihoods(&mut self) -> &Vec<Vec<Gaussian>> {
let m_t_ft = self.likelihood_teams();
self.likelihoods = self
.teams
.iter()
.zip(self.weights.iter())
.zip(m_t_ft)
.map(|((p, w), m)| {
let performance = p.iter().zip(w.iter()).fold(N00, |p, (player, &weight)| {
p + (player.performance() * weight)
});
p.iter()
.zip(w.iter())
.map(|(p, &w)| {
((m - performance.exclude(p.performance() * w)) * (1.0 / w))
.forget(p.beta, 1)
})
.collect::<Vec<_>>()
})
.collect::<Vec<_>>();
&self.likelihoods
}
fn likelihood_teams(&mut self) -> Vec<Gaussian> {
let o = sort_perm(&self.result, true);
let mut t = o
.iter()
.map(|&e| {
let performance = self.teams[e]
.iter()
.zip(self.weights[e].iter())
.fold(N00, |p, (player, &weight)| {
p + (player.performance() * weight)
});
TeamMessage {
prior: performance,
likelihood_lose: N_INF,
likelihood_win: N_INF,
likelihood_draw: N_INF,
}
})
.collect::<Vec<_>>();
let mut d = t
.windows(2)
.map(|w| DiffMessage {
prior: w[0].prior - w[1].prior,
likelihood: N_INF,
})
.collect::<Vec<_>>();
let tie = o
.windows(2)
.map(|e| self.result[e[0]] == self.result[e[1]])
.collect::<Vec<_>>();
let margin = if self.p_draw == 0.0 {
vec![0.0; o.len() - 1]
} else {
o.windows(2)
.map(|w| {
if self.p_draw == 0.0 {
0.0
} else {
let a: f64 = self.teams[w[0]].iter().map(|a| a.beta.powi(2)).sum();
let b: f64 = self.teams[w[1]].iter().map(|a| a.beta.powi(2)).sum();
compute_margin(self.p_draw, (a + b).sqrt())
}
})
.collect::<Vec<_>>()
};
self.evidence = 1.0;
let mut step = (f64::INFINITY, f64::INFINITY);
let mut iter = 0;
while tuple_gt(step, 1e-6) && iter < 10 {
step = (0.0, 0.0);
for e in 0..d.len() - 1 {
d[e].prior = t[e].posterior_win() - t[e + 1].posterior_lose();
if iter == 0 {
self.evidence *= evidence(&d, &margin, &tie, e);
}
d[e].likelihood = approx(d[e].prior, margin[e], tie[e]) / d[e].prior;
let likelihood_lose = t[e].posterior_win() - d[e].likelihood;
step = tuple_max(step, t[e + 1].likelihood_lose.delta(likelihood_lose));
t[e + 1].likelihood_lose = likelihood_lose;
}
for e in (1..d.len()).rev() {
d[e].prior = t[e].posterior_win() - t[e + 1].posterior_lose();
if iter == 0 && e == d.len() - 1 {
self.evidence *= evidence(&d, &margin, &tie, e);
}
d[e].likelihood = approx(d[e].prior, margin[e], tie[e]) / d[e].prior;
let likelihood_win = t[e + 1].posterior_lose() + d[e].likelihood;
step = tuple_max(step, t[e].likelihood_win.delta(likelihood_win));
t[e].likelihood_win = likelihood_win;
}
iter += 1;
}
if d.len() == 1 {
self.evidence = evidence(&d, &margin, &tie, 0);
d[0].prior = t[0].posterior_win() - t[1].posterior_lose();
d[0].likelihood = approx(d[0].prior, margin[0], tie[0]) / d[0].prior;
}
let t_end = t.len() - 1;
let d_end = d.len() - 1;
t[0].likelihood_win = t[1].posterior_lose() + d[0].likelihood;
t[t_end].likelihood_lose = t[t_end - 1].posterior_win() - d[d_end].likelihood;
o.iter().map(|&e| t[e].likelihood()).collect::<Vec<_>>()
}
pub fn posteriors(&self) -> Vec<Vec<Gaussian>> {
self.likelihoods
.iter()
.zip(self.teams.iter())
.map(|(l, t)| {
l.iter()
.zip(t.iter())
.map(|(&l, p)| l * p.prior)
.collect::<Vec<_>>()
})
.collect::<Vec<_>>()
}
}
#[cfg(test)]
mod tests {
use ::approx::assert_ulps_eq;
use crate::{Gaussian, Player, GAMMA};
use super::*;
#[test]
fn test_1vs1() {
let t_a = Player::new(Gaussian::new(25.0, 25.0 / 3.0), 25.0 / 6.0, 25.0 / 300.0);
let t_b = Player::new(Gaussian::new(25.0, 25.0 / 3.0), 25.0 / 6.0, 25.0 / 300.0);
let g = Game::new(vec![vec![t_a], vec![t_b]], vec![0.0, 1.0], vec![], 0.0);
let p = g.posteriors();
let a = p[0][0];
let b = p[1][0];
assert_eq!(a.mu, 20.79477925612302);
assert_eq!(b.mu, 29.205220743876975);
assert_eq!(a.sigma, 7.194481422570443);
let t_a = Player::new(Gaussian::new(29.0, 1.0), 25.0 / 6.0, GAMMA);
let t_b = Player::new(Gaussian::new(25.0, 25.0 / 3.0), 25.0 / 6.0, GAMMA);
let g = Game::new(vec![vec![t_a], vec![t_b]], vec![0.0, 1.0], vec![], 0.0);
let p = g.posteriors();
let a = p[0][0];
let b = p[1][0];
assert_eq!(a.mu, 28.896475351225412);
assert_eq!(a.sigma, 0.9966043313004235);
assert_eq!(b.mu, 32.18921172045737);
assert_eq!(b.sigma, 6.062063735879715);
let t_a = Player::new(Gaussian::new(1.139, 0.531), 1.0, 0.2125);
let t_b = Player::new(Gaussian::new(15.568, 0.51), 1.0, 0.2125);
let g = Game::new(vec![vec![t_a], vec![t_b]], vec![0.0, 1.0], vec![], 0.0);
assert_eq!(g.likelihoods[0][0].sigma, f64::INFINITY);
assert_eq!(g.likelihoods[1][0].sigma, f64::INFINITY);
assert_eq!(g.likelihoods[0][0].mu, 0.0);
}
#[test]
fn test_1vs1vs1() {
let teams = vec![
vec![Player::new(
Gaussian::new(25.0, 25.0 / 3.0),
25.0 / 6.0,
25.0 / 300.0,
)],
vec![Player::new(
Gaussian::new(25.0, 25.0 / 3.0),
25.0 / 6.0,
25.0 / 300.0,
)],
vec![Player::new(
Gaussian::new(25.0, 25.0 / 3.0),
25.0 / 6.0,
25.0 / 300.0,
)],
];
let g = Game::new(teams.clone(), vec![1.0, 2.0, 0.0], vec![], 0.0);
let p = g.posteriors();
let a = p[0][0];
let b = p[1][0];
assert_eq!(a.mu, 25.00000000000592);
assert_eq!(a.sigma, 6.238469796269066);
assert_eq!(b.mu, 31.31135822129149);
assert_eq!(b.sigma, 6.69881865477675);
let g = Game::new(teams.clone(), vec![], vec![], 0.0);
let p = g.posteriors();
let a = p[0][0];
let b = p[1][0];
assert_eq!(a.mu, 31.31135822129149);
assert_eq!(a.sigma, 6.69881865477675);
assert_eq!(b.mu, 25.00000000000592);
assert_eq!(b.sigma, 6.238469796269066);
let g = Game::new(teams, vec![1.0, 2.0, 0.0], vec![], 0.5);
let p = g.posteriors();
let a = p[0][0];
let b = p[1][0];
let c = p[2][0];
assert_eq!(a.mu, 24.999999999511545);
assert_eq!(a.sigma, 6.092561128305945);
assert_eq!(b.mu, 33.37931495595287);
assert_eq!(b.sigma, 6.483575782278924);
assert_eq!(c.mu, 16.62068504453558);
assert_eq!(c.sigma, 6.483575782198122);
}
#[test]
fn test_1vs1_draw() {
let t_a = Player::new(Gaussian::new(25.0, 25.0 / 3.0), 25.0 / 6.0, 25.0 / 300.0);
let t_b = Player::new(Gaussian::new(25.0, 25.0 / 3.0), 25.0 / 6.0, 25.0 / 300.0);
let g = Game::new(vec![vec![t_a], vec![t_b]], vec![0.0, 0.0], vec![], 0.25);
let p = g.posteriors();
let a = p[0][0];
let b = p[1][0];
assert_eq!(a.mu, 24.999999999999996);
assert_eq!(a.sigma, 6.469480769842277);
assert_eq!(b.mu, 24.999999999999996);
assert_eq!(b.sigma, 6.469480769842277);
let t_a = Player::new(Gaussian::new(25.0, 3.0), 25.0 / 6.0, 25.0 / 300.0);
let t_b = Player::new(Gaussian::new(29.0, 2.0), 25.0 / 6.0, 25.0 / 300.0);
let g = Game::new(vec![vec![t_a], vec![t_b]], vec![0.0, 0.0], vec![], 0.25);
let p = g.posteriors();
let a = p[0][0];
let b = p[1][0];
assert_eq!(a.mu, 25.73600181056662);
assert_eq!(a.sigma, 2.709956162204711);
assert_eq!(b.mu, 28.67288808419261);
assert_eq!(b.sigma, 1.9164711604544398);
}
#[test]
fn test_1vs1vs1_draw() {
let t_a = Player::new(Gaussian::new(25.0, 25.0 / 3.0), 25.0 / 6.0, 25.0 / 300.0);
let t_b = Player::new(Gaussian::new(25.0, 25.0 / 3.0), 25.0 / 6.0, 25.0 / 300.0);
let t_c = Player::new(Gaussian::new(25.0, 25.0 / 3.0), 25.0 / 6.0, 25.0 / 300.0);
let g = Game::new(
vec![vec![t_a], vec![t_b], vec![t_c]],
vec![0.0, 0.0, 0.0],
vec![],
0.25,
);
let p = g.posteriors();
let a = p[0][0];
let b = p[1][0];
let c = p[2][0];
assert_eq!(a.mu, 24.999999999999996);
assert_eq!(a.sigma, 5.729068664890827);
assert_eq!(b.mu, 25.000000000000004);
assert_eq!(b.sigma, 5.707423522433266);
assert_eq!(c.mu, 24.999999999999996);
assert_eq!(c.sigma, 5.729068664890825);
let t_a = Player::new(Gaussian::new(25.0, 3.0), 25.0 / 6.0, 25.0 / 300.0);
let t_b = Player::new(Gaussian::new(25.0, 3.0), 25.0 / 6.0, 25.0 / 300.0);
let t_c = Player::new(Gaussian::new(29.0, 2.0), 25.0 / 6.0, 25.0 / 300.0);
let g = Game::new(
vec![vec![t_a], vec![t_b], vec![t_c]],
vec![0.0, 0.0, 0.0],
vec![],
0.25,
);
let p = g.posteriors();
let a = p[0][0];
let b = p[1][0];
let c = p[2][0];
assert_eq!(a.mu, 25.48850755025261);
assert_eq!(a.sigma, 2.6382084442984226);
assert_eq!(b.mu, 25.510671709901217);
assert_eq!(b.sigma, 2.6287517663583633);
assert_eq!(c.mu, 28.555920328820527);
assert_eq!(c.sigma, 1.8856891308577184);
}
#[test]
fn test_1vs1_weighted() {
let w_a = vec![1.0];
let w_b = vec![2.0];
let t_a = vec![Player::new(
Gaussian::new(25.0, 25.0 / 3.0),
25.0 / 6.0,
0.0,
)];
let t_b = vec![Player::new(
Gaussian::new(25.0, 25.0 / 3.0),
25.0 / 6.0,
0.0,
)];
let g = Game::new(vec![t_a.clone(), t_b.clone()], vec![], vec![w_a, w_b], 0.0);
let p = g.posteriors();
assert_ulps_eq!(
p[0][0],
Gaussian::new(30.625173, 7.765472),
epsilon = 0.000001
);
assert_ulps_eq!(
p[1][0],
Gaussian::new(13.749653, 5.733840),
epsilon = 0.000001
);
let w_a = vec![1.0];
let w_b = vec![0.7];
let g = Game::new(vec![t_a.clone(), t_b.clone()], vec![], vec![w_a, w_b], 0.0);
let p = g.posteriors();
assert_ulps_eq!(
p[0][0],
Gaussian::new(27.630080, 7.206676),
epsilon = 0.000001
);
assert_ulps_eq!(
p[1][0],
Gaussian::new(23.158943, 7.801628),
epsilon = 0.000001
);
let w_a = vec![1.6];
let w_b = vec![0.7];
let g = Game::new(vec![t_a, t_b], vec![], vec![w_a, w_b], 0.0);
let p = g.posteriors();
assert_ulps_eq!(
p[0][0],
Gaussian::new(26.142438, 7.573088),
epsilon = 0.000001
);
assert_ulps_eq!(
p[1][0],
Gaussian::new(24.500183, 8.193278),
epsilon = 0.000001
);
let w_a = vec![1.0];
let w_b = vec![0.0];
let t_a = vec![Player::new(Gaussian::new(2.0, 6.0), 1.0, 0.0)];
let t_b = vec![Player::new(Gaussian::new(2.0, 6.0), 1.0, 0.0)];
let g = Game::new(vec![t_a, t_b], vec![], vec![w_a, w_b], 0.0);
let p = g.posteriors();
assert_ulps_eq!(
p[0][0],
Gaussian::new(5.55706798109105, 4.0528268357577995),
epsilon = 0.000001
);
assert_ulps_eq!(p[1][0], Gaussian::new(2.0, 6.0), epsilon = 0.000001);
let w_a = vec![1.0];
let w_b = vec![-1.0];
let t_a = vec![Player::new(Gaussian::new(2.0, 6.0), 1.0, 0.0)];
let t_b = vec![Player::new(Gaussian::new(2.0, 6.0), 1.0, 0.0)];
let g = Game::new(vec![t_a, t_b], vec![], vec![w_a, w_b], 0.0);
let p = g.posteriors();
assert_ulps_eq!(p[0][0], p[1][0], epsilon = 0.000001);
}
}