prediction-pool-optimizer
Turn a prediction pool's scoring rules plus a consensus of the major
bookmakers' odds into the answer that maximizes expected points — not
the most likely outcome — for every open question in the pool: match
scores AND every bonus / award / special question (top scorer, group
winners, champion, most cards …). Sport-agnostic core with per-sport
probability blocks. Consumed by /prediction-pool.
The optimization target is the pool's score, so the chain is always
rules → odds → expected value → participant field → answer, never
"who wins this match?".
When to use
Use when someone wants the best tips for a prediction / betting pool
(kicktipp-style company pools — football WM, basketball WM, …) and the
target is pool points, not match truth. Triggered by the
/prediction-pool command (Steps 3–5) or directly
when a user asks to optimize / maximize their pool picks.
The one idea that makes this skill correct: the highest-probability
result is not the highest-expected-value tip. Under most pool rules a
2:1 or 1:0 scores the same partial points as the "obvious" pick but hits
more often; under quote/rarity rules a rare-but-plausible result is worth
more. Always optimize the pool's points, never the truth of the match.
Hard rules
- Rules before tips. Never produce a tip before the pool's scoring is
parsed (Procedure step 1). Strategy is a function of the rules.
- Answer EVERY open question. A pool has scores and bonus / award /
special questions ("which team supplies the top scorer?", "most yellow
cards?", "champion?"). Producing scorelines only and leaving the bonus
questions blank is a failed run — enumerate every open question in
step 1 and carry each to an answer (steps 5–6). No silent skips.
- Odds are the primary signal — as a multi-book consensus, not one book.
Bookmaker / market probabilities already fold in form, squad, injuries,
travel, climate. Build the base from a consensus across the 5–10 biggest
publicly-viewable books (step 2), de-vigged, sharpness-weighted — never
mirror a single portal. Only override with current information (confirmed
lineups, late injuries, suspensions, manager change).
- No invented numbers. Emit no probability you cannot derive from real
odds or from actually executed code. Tournament/outright/award numbers
come from real markets or the executed Poisson helper — never a claimed
"I ran 10,000 simulations".
- Scorelines are computed, not guessed. The EV-max tip per match comes
from the executed grid optimiser (
score_ev.ts, step 4a), never the eye. A
3:2 / 4:1 / 1:4 in the output is the signature of a skipped computation.
- One-sentence justification per answer. Short.
Procedure
1. Parse the pool rules AND enumerate every open question
From the pool's rule page, extract and document:
- Points for exact result / goal (point) difference / tendency.
- Every bonus / award / special question the pool asks (champion, top
scorer, "team of the top scorer", group winners, most cards, longest
unbeaten, will-there-be-a-red-card, over/under totals …). Write them all
down as an explicit checklist — this list is the run's contract; every
entry must reach an answer.
- Joker / multiplier rules, per-question point weights.
- Quote / rarity scoring (rare correct tips score more)? — flips the
whole strategy toward contrarian (step 4).
- Special scorings, per-question deadlines, and strategy limits
(e.g. max N identical tips).
- The goal: place well, or win a large pool? (changes variance — step 4.)
2. Build the data base — a consensus across the major books
Primary signal: current bookmaker odds, but aggregated across the 5–10
biggest publicly-viewable books, not a single portal:
- Collect the odds for each market (1X2, exact-score, outrights, and
each special/award market a bonus question needs) from several books.
Odds-comparison aggregators (Oddschecker, Oddsportal / Betexplorer) show
many books at once; supplement with named books. Concrete book list and
the weighting recipe live in
reference/odds-and-bonus.md.
- De-vig each book independently (remove its margin) → per-book implied
probabilities. Raw odds sum to >100%; never treat them as probabilities.
- Aggregate with a healthy weighting, not a blind average: weight
sharp, low-margin books higher (Pinnacle, Betfair Exchange) and
recreational books lower; use a weighted mean or a trimmed median so one
outlier book cannot swing the base. The result is the consensus
probability — the calibration base.
- Treat a single book's outlier as a flag, not a truth — investigate
why (a known injury already priced? a stale line?) before moving off
consensus. Cross-portal agreement is signal; one portal disagreeing is a
prompt to check, not to follow.
Secondary (only when it adds signal the consensus has not yet absorbed):
confirmed lineups, injuries, suspensions, manager change, recent form, home
advantage, head-to-head, rest/travel, weather, model forecasts (Opta),
Elo/SPI ratings.
3. Per-match probabilities (sport block)
Compute, per match, the outcome distribution and the most plausible exact
results. Pick the block for the event's sport:
Football / soccer
- Model goals as Poisson per side from each team's expected goals;
draws are real (~22–28% baseline) — people under-tip them.
- Outcome split: home-win / draw / away-win; then the exact-score grid.
- Common EV-strong exact results: 1:0, 2:1, 1:1, 2:0.
Basketball
- No draws. Model the points margin as roughly Gaussian around the
market spread; pair with the moneyline for win probability and the
total (over/under) for the score level.
- Tendency = sign of (margin); "exact result" rules are rare — read step 1.
Generic fallback (other sports)
- Derive the outcome split straight from de-vigged moneyline odds; estimate
a plausible score from the market total. State the model used.
Cross-check the model against the consensus; on a large divergence, re-check
the data and explain the cause before trusting it.
4. Convert to the EV-maximizing tip
Map probabilities to the tip with the highest expected points under the
step-1 rules — not the prettiest match.
4a. The EV-max scoreline is computed, never eyeballed
Do not hand-pick a scoreline. Run the executed grid optimiser — it builds
the full Poisson score grid and returns the expected-points-max tip under the
step-1 point tiers:
npx tsx node_modules/@event4u/agent-config/src/scripts/prediction-pool/score_ev.ts --lh <home-xg> --la <away-xg> \
--tendency <t> --diff <d> --exact <e> # one match
npx tsx node_modules/@event4u/agent-config/src/scripts/prediction-pool/score_ev.ts matches.json \
--tendency <t> --diff <d> --exact <e> # batch, prints a ranked table
Two facts the grid makes unavoidable — and intuition gets wrong:
-
High scorelines are almost never EV-max. Under any partial-points rule a
moderate favourite peaks at 1:0 / 2:0 / 2:1; 1:0 wins surprisingly
often, and the top of the EV surface is flat (1:0 vs 2:1 vs 2:0 separated
by hundredths). A 3:2 / 4:1 / 1:4 tip is never the optimum — if a tip like
that appears, the grid was not run.
-
Draws are under-tipped. A correctly-tipped draw banks the goal-difference
tier on every draw scoreline, so in a close match (xG within ~0.4) a 1:1 can
out-score a 1:0. The grid surfaces this; the eye does not. People tip too few
draws — let the computation, not the gut, decide.
-
Standard fixed-point scoring + goal "place well" → tip the grid's
EV-max per match. No contrarian — only your tip matters for your score,
so deliberately tipping "different" just burns EV.
-
Quote / rarity scoring → weigh rarer-but-plausible results against their
higher payout; take rarity when payout × probability wins (raise --exact
weight or post-process the ranked table by the multiplier).
4b. Large pool, goal "win it" — measure P(finish 1st), don't guess
When the goal is to win a large pool (not place), the target flips from
E(points) to P(finish ahead of the whole field) — and pure EV-max converges
with the crowd, so it cannot open a gap. Measure it with the executed field
simulator instead of a "rough Kelly" hand-wave:
npx tsx node_modules/@event4u/agent-config/src/scripts/prediction-pool/pool_winsim.ts pool.json --runs 4000 --max-flips 4
It models the field as softmax-EV tippers, reports P(win) for the
EV-max-everywhere baseline, then greedily reports which few tips to flip
off EV-max (and the EV cost + P(win) gain of each). Read the output as the
field threshold, empirically:
- Pool N < 20 → the sim shows flips barely move P(win); maximize EV, ignore
the field.
- 20 ≤ N < 100 and you are in the prize positions → maximize EV.
- N ≥ 100, or you are outside the top ~20% → take the simulator's
suggested flips: a handful of higher-variance scorelines on high-consensus
matches lift P(win) most per unit of EV given up. Flip only what the sim says
pays — variance you don't need is wasted EV.
Respect all strategy limits from step 1 (max identical tips, etc.).
5. Tournament, bonus & special questions — answer every one (no hallucination)
Walk the step-1 checklist and answer each entry. Pick the method by
question type — full taxonomy + per-type method in
reference/odds-and-bonus.md:
-
Tournament structure (group winners, KO rounds, finalists, champion):
use real outright market odds ("to win group", "to reach final",
"outright winner") aggregated per step 2, or the executed Poisson
tournament simulator:
npx tsx node_modules/@event4u/agent-config/src/scripts/prediction-pool/poisson_sim.ts <teams-xg.json> --runs 20000
It plays the bracket from per-team expected goals and prints empirical
advancement / title probabilities. Run it — never report simulated
numbers you did not actually compute.
-
Award / player markets (top scorer, most assists, "which team supplies
the top scorer", golden boot, most cards): use the matching special
market — e.g. aggregate per-player "top goalscorer" odds by team to
answer "which team has the top scorer". Where no clean market exists, derive
from a stated model (e.g. squad strength × games-expected) and label it
as a model estimate, not a market number.
-
Binary / over-under specials (will there be a red card, over/under total
goals/cards): take the de-vigged consensus probability for the line and pick
the EV-max side under the question's point weight.
Optimize every answer on the same expected-points basis as the scores. Re-run
as late as each question's deadline allows: re-check confirmed lineups,
injuries, suspensions, and odds movement, then adjust. The per-question
deadline is the only hard constraint.
Output format
-
Approval table — one row per match:
Match | Tip | Prob / EV | Risk (low/med/high) | 1-line reason | Books used
Books used names the consensus base (e.g. "consensus of 7 books, sharp-weighted").
-
Bonus & special answers — one row per open question from the step-1
checklist, every entry answered (none left blank):
Question | Answer | Prob / EV | Risk | 1-line reason | Source (market / model)
-
Group standings and the full bracket where the event has them.
-
Self-check note — (a) confirm the tips reconcile with
reference/ev-fixtures.md (known pool rules +
market odds → a known-good EV tip); (b) confirm the bonus table has the
same number of rows as the step-1 checklist — a shorter table means a
question was dropped. If your method disagrees with a fixture, your method
is wrong — find the error (usually a forgotten partial-points term,
un-de-vigged odds, or following one book instead of the consensus), don't
ship the tip.
Handed back to /prediction-pool for the approval
gate — the skill never enters or submits anything.
Gotcha
- Answering only the scores. A pool's bonus / award questions carry real
points; leaving them blank because they are "not a scoreline" silently
forfeits them. The step-1 checklist exists so every question is answered.
- Following one portal. A single book can be stale or shaded; build the
base from a sharp-weighted consensus across several and treat an outlier as
a flag to investigate, not a number to copy.
- Tipping the modal result, not the EV-maximal one. The single most
likely scoreline rarely maximizes partial points — run
score_ev.ts across
the result grid, don't eyeball the favourite.
- Hand-picking a high scoreline. 3:2 / 4:1 / 1:4 are never EV-max under
partial-points rules — moderate favourites peak at 1:0 / 2:0 / 2:1. A high
tip in the output means the grid was skipped; run
score_ev.ts.
- Under-tipping draws. A correct draw banks the goal-difference tier on
every draw scoreline, so in a close match a 1:1 can beat a 1:0. Let the grid
decide; the eye tips too few draws.
- "Rough Kelly" variance for a large pool. Don't guess how much to deviate
— run
pool_winsim.ts; it returns the exact flips that raise P(finish 1st)
most per unit of EV given up.
- Forgetting to de-vig. Raw bookmaker odds sum to >100%; treating them
as probabilities inflates the favourite. Remove the margin per book
before aggregating.
- Contrarian under fixed points. Deviating "to stand out" only helps
under quote/rarity rules or a win-a-large-pool goal — otherwise it burns EV.
- Claimed-but-unrun simulation. Numbers like "I ran 10,000 tournaments"
without executing
poisson_sim.ts are hallucinated — run the code or use
outright odds.
Do NOT
- Leave any open pool question (bonus / award / special) unanswered.
- Build the base from a single bookmaker, or skip de-vigging before aggregating.
- Tip the most likely result instead of the EV-maximal one.
- Hand-pick a scoreline instead of running
score_ev.ts — and never emit a
3:2 / 4:1 / 1:4 tip, which is never EV-max under partial points.
- Go contrarian under standard fixed-point scoring with a "place well" goal.
- Guess large-pool variance ("rough Kelly") instead of running
pool_winsim.ts.
- Report Monte-Carlo numbers without running
poisson_sim.ts / pool_winsim.ts.
- Treat raw odds as probabilities without removing the vig.
- Give betting or financial advice — this optimizes a game; the human submits.
See also
/prediction-pool — the orchestrator (event,
persistence, Playwright entry, gates).
reference/odds-and-bonus.md — the major-book
list + sharpness-weighted consensus recipe, and the bonus / award / special
question taxonomy with a per-type method.
reference/ev-fixtures.md — known-good
rules+odds → EV examples.
node_modules/@event4u/agent-config/src/scripts/prediction-pool/score_ev.ts —
the executed exact-score EV optimiser (step 4a; λ + rule → EV-max scoreline).
node_modules/@event4u/agent-config/src/scripts/prediction-pool/pool_winsim.ts —
the executed field model + P(finish 1st) simulator and flip-finder (step 4b).
node_modules/@event4u/agent-config/src/scripts/prediction-pool/poisson_sim.ts —
the executed tournament simulator (step 5).