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Odds Generation — run · inning (cricket)

Pick the format (T20/ODI), say who bats first, and enter the batting-first innings total in Malay plus the Match Winner in decimal — margins still embedded. A limited-overs innings is overs of six balls scoring {0, 1, 2, 3, 4, 6}, so the model is compound from the ball up (ADR-029):

  1. strips both margins (Power method) to fair targets;
  2. builds ball → over → innings under a phase curve (powerplay / middle / death — cricket's quarter weights) and back-solves the two innings abilities: the innings line fixes μ₁, the Match Winner fixes μ₂;
  3. independent overs come out far too thin (σ ≈ 15 vs ≈ 28 real), so a day-form mixture G = 1 + τZ scales every over and τ is solved to the dispersion prior — collapses and flat tracks correlate overs;
  4. the chase truncates: the second innings stops at the target (won chases pile up just past it, failed ones fall short), scores level is the tie — the 1X2's third leg, settled by the super over in T20 — so 2nd-innings Over/Unders price off the settled distribution, not the ability;
  5. group runs (the powerplay) and single-over markets read the same phase curve and mixture, consistent with the innings by construction.
Stage 1 — ball → over → innings: per-ball outcomes {0,1,2,3,4,6} compound six to an over and twenty to the innings under the powerplay/middle/death phase curve
Stage 1 — compound from the ball up: {0, 1, 2, 3, 4, 6} per ball, ×6 into an over, ×20 into the innings — weighted by the powerplay / middle / death phase curve

Wickets and resource decay are folded into the phase curve and mixture rather than modelled per ball — the honest limit of a quotes-anchored page; ball-level state belongs to the ADR-029 phase-2 engine.

Innings 1 total (Malay) — Home bats
Match Winner (Decimal)
Shape priors · margins
Phase shares % (PP · middle · death)

/ steps a field, Shift steps bigger; the Malay pair steps its partner the opposite way. Quotes: the batting-first innings total + the match winner; the second innings and every segment derive from the same model.

Valid inputs: Malay in [−1, +1] non-zero, decimals above 1, each book carrying margin, σ above ~8. The solve mixes 7 form nodes over 20 overs — allow it a second or two.

μ₁ 166.52μ₂ 162.47τ 0.1371σ₁ 28.00tie 1.0%round-trip Δp 4.9e-7 / 1.9e-7Overs → Form τ → Chase
Innings runs — P(runs ∈ bin) ×100 · bins of 10
μ₁ 166.5μ₂ 162.5τ 0.137σ₁ 28.0tie 1.0%
90100110120130140150160170180190200210220230240250
Innings 1 (Home)0.21.02.75.48.411.112.913.512.810.98.55.93.61.90.90.30.1
Innings 2 (Away) — settled0.52.15.610.514.917.216.613.69.45.52.61.00.30.10.00.00.0
the settled second innings piles up just past the target (won chases stop) and spreads low (failed chases fall short)
2 in scope
the third leg is scores-level — a T20 tie heads to the super over
OutcomeFairDecPriced
Home53.5%1.8681.800
Draw (tie)1.0%100.69349.393
Away45.5%2.1992.109
How these numbers are computed
1 · Strip the bookmaker margins (Power method)
Innings 1 total 165.5 → P(over)
OverUnder
Malay quote+0.90+0.92
Decimal dd1.90001.9200
Implied q=1/dq = 1/d0.52630.5208
Fair p=q1/xp = q^{1/x}0.50280.4972
Fair decimal 1/p1/p1.98882.0113
overround Q = 1.0471 → solve q11/x+q21/x=1q_1^{1/x} + q_2^{1/x} = 1 → x = 0.9335fair P(over) = 50.28%
Match Winner → P(chasing side wins)
HomeAway
Decimal quote1.802.10
Decimal dd1.80002.1000
Implied q=1/dq = 1/d0.55560.4762
Fair p=q1/xp = q^{1/x}0.54030.4597
Fair decimal 1/p1/p1.85092.1752
overround Q = 1.0317 → solve q11/x+q21/x=1q_1^{1/x} + q_2^{1/x} = 1 → x = 0.9547fair P(chase wins) = 45.97%

Standalone strips: Margin — two-way (Power).

2 · Ball → over → innings, and why independent overs are not enough

A ball scores {0, 1, 2, 3, 4, 6}; six balls convolve into an over, and the innings convolves 20 overs under a phase curve — powerplay / middle / death get 29/41/30% of the runs across 6/9/5 overs (cricket's quarter weights). But independent overs give σ ≈ 18.8 — real innings run σ ≈ 28.0 because collapses and flat tracks correlate every over. The fix is a day-form mixture: every over's mean scales by G=1+τZG = 1 + \tau Z, and τ is solved so the innings dispersion hits the prior:

Stageμ₁μ₂τσ₁tieΔ overΔ ML
Overs166.0163.40.00018.81.5%1.9e-74.3e-7
Form τ166.5162.50.13728.01.0%4.9e-71.9e-7
Chase166.5162.50.13728.01.0%4.9e-71.9e-7

Each stage re-solves both fair targets: the innings line pins μ₁ (size) and the Match Winner pins μ₂ (the chasing ability) — with ties heading to the super over, the ML read is P(chase wins)+12P(tie)P(\text{chase wins}) + \tfrac{1}{2}P(\text{tie}).

3 · The chase — the second innings truncates at the target

Whoever bats second stops the moment the target falls: with a first-innings score r1r_1 and chasing ability A2A_2,

r2={A2A2r1    (failed chase — or the tie at A2=r1)r1+1+UA2r1+1    (won — U is the winning hit’s overshoot)r_2 = \begin{cases} A_2 & A_2 \le r_1 \;\; \text{(failed chase — or the tie at } A_2 = r_1\text{)} \\ r_1 + 1 + U & A_2 \ge r_1 + 1 \;\; \text{(won — } U \text{ is the winning hit's overshoot)} \end{cases}

which is why the settled second-innings pmf (the Chase stage in the panel) piles up just past the target and never shows the ability tail — and why 2nd-innings Over/Unders must price off the settled distribution, not the ability. Who wins is truncation-free, so μ₂ matches the Form stage. The tie mass P = 1.0% is the 1X2's third leg.

4 · Read “1X2” · margins · notes

Three legs: batting-first side wins, scores level (the tie), chasing side wins — read off P(A₂ vs the target). Fair groups are re-margined exactly as in goal-regular (Power ladder two-way, Shin multi-way).

targets  tO = powerStrip(innings pair)     tW = powerStrip(match-winner pair)

stage ∈ {Overs (τ=0), Form τ, Chase}:          # each re-solves the same targets
  sweep: bisect μ₁ until P(runs₁ > line) = tO
         bisect τ  until sd(innings₁)   = σ prior          # Form/Chase stages
  bisect μ₂ until P(chase wins) + ½·P(tie) = tW

innings: ball pmf(mean) → over (6-fold conv) → phase curve over 20 overs
         → mix over day-form G = 1 + τZ (7 nodes)
chase:   r₂ = A₂ if short; = target + overshoot if won; level = tie (super over)

Wickets/resource decay are folded into the phase curve and mixture rather than modelled per ball — the honest limit of a quotes-anchored page (ADR-029 phase 2 owns ball-level state). Engine + invariants: docs/src/lib/odds/cricket.ts, __tests__/cricket.test.ts.