Example #1
0
func AssertRating(t *testing.T, expectedMean, expectedStddev float64, actual skills.Rating) {
	if r := actual.Mean(); math.Abs(r-expectedMean) > errorTolerance {
		t.Errorf("actual.Mean = %v, want %v\n%v", r, expectedMean, testLoc())
	}
	if r := actual.Stddev(); math.Abs(r-expectedStddev) > errorTolerance {
		t.Errorf("actual.Stddev = %v, want %v\n%v", r, expectedStddev, testLoc())
	}
}
Example #2
0
func srating2rating(s skills.Rating) Rating {
	return Rating{Mean: s.Mean(), Stddev: s.Stddev()}
}
Example #3
0
func twoPlayerCalcNewRating(gi *skills.GameInfo, selfRating, oppRating skills.Rating, comparison int) skills.Rating {
	drawMargin := drawMarginFromDrawProbability(gi.DrawProbability, gi.Beta)

	c := math.Sqrt(numerics.Sqr(selfRating.Stddev()) + numerics.Sqr(oppRating.Stddev()) + 2*numerics.Sqr(gi.Beta))

	winningMean := selfRating.Mean()
	losingMean := oppRating.Mean()

	if comparison == skills.Lose {
		winningMean = oppRating.Mean()
		losingMean = selfRating.Mean()
	}

	meanDelta := winningMean - losingMean

	var v, w, rankMultiplier float64

	if comparison != skills.Draw {
		v = vExceedsMarginC(meanDelta, drawMargin, c)
		w = wExceedsMarginC(meanDelta, drawMargin, c)
		rankMultiplier = float64(comparison)
	} else {
		v = vWithinMarginC(meanDelta, drawMargin, c)
		w = wWithinMarginC(meanDelta, drawMargin, c)
		rankMultiplier = 1
	}

	meanMultiplier := (numerics.Sqr(selfRating.Stddev()) + numerics.Sqr(gi.DynamicsFactor)) / c

	varianceWithDynamics := numerics.Sqr(selfRating.Stddev()) + numerics.Sqr(gi.DynamicsFactor)
	stdDevMultiplier := varianceWithDynamics / numerics.Sqr(c)

	newMean := selfRating.Mean() + (rankMultiplier * meanMultiplier * v)
	newStdDev := math.Sqrt(varianceWithDynamics * (1 - w*stdDevMultiplier))

	return skills.NewRating(newMean, newStdDev)
}