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Tournament, runouts, and bots

Walkthroughs for three APIs that are especially useful in tournament tools, study backends, and decideAction-style bots: runout equity spread, chop math, and range-aware regret on a street.

1. Runout equity spread (exactHeroEquityRunoutQuantiles)​

Mean equity on a draw-heavy flop hides bad runouts. Enumerate all turn/river completions and read the distribution:

const poker = require('poker-calculations');

const hero = ['Ah', 'Kh'];
const flop = ['Qh', 'Jh', '2c'];

const q = poker.exactHeroEquityRunoutQuantiles(hero, flop);
console.log(q);
// { mean, variance, p05, p50, p95, n }

Use exactHeroEquityRunoutQuantilesAsync when you pass a weighted villain range or need a non-blocking call in a server.

2. Shapley chop vs Harville ICM (icmShapleyValues)​

Compare a chip-proportional chop to standard ICM and to Shapley fair division when players negotiate a deal:

const stacks = [12000, 8000, 5000, 2000];
const payouts = [10000, 6000, 3000, 1000];

const icm = poker.icmExpectedPayouts(stacks, payouts);
const shapley = poker.icmShapleyValues(stacks, payouts, { method: 'exact' });
console.log({ icm, shapley: shapley.values });

3. Information regret on one street (exactInformationRegretVsClairvoyant)​

Measure how much call/fold EV you give up when you only see the current board, not the final runout, against a weighted range:

const range = new Float64Array(1326);
range.fill(1 / 1326);

const regret = poker.exactInformationRegretVsClairvoyant(
  ['Ah', 'Kh'],
  ['Qh', 'Jh', '2c'],
  range,
  100,
  50
);
console.log('EV gap (chips):', regret);

Related APIs: icmHarvilleStackJacobian, exactEquityCardRemovalGradient, bayesianRangeUpdateFromAction, materializeVillainRangeAfterBlockers.