reading-a-racecard

name	reading_a_racecard
description	How to read a racecard honestly — barrier/weight/form/scratchings, converting prices to fair probability (overround/vig), cross-book best price, and exotics.
triggers	["racecard","race card","scratchings","barrier","form string","each-way","same race multi","srm"]

Reading a racecard

A racecard is the runners for one race with the facts that move prices. Read it in this order, and never quote a price without checking for late scratchings first.

Fields that matter

• Barrier (gate/box) — inside draws suit some tracks/distances; wide draws cost ground. Note it; don't over-weight it.
• Weight — handicaps carry weight to level the field; a big weight rise on a proven horse is a negative, a drop a positive.
• Jockey / driver / trainer — strike-rate context, not destiny. Top stables and hoops shorten prices; that's often already in the market.
• Form string — recent placings (e.g. 1-3x2): x = a spell, numbers = finish positions, 0 = out of the placings. Recency and class of those runs matter more than the raw numbers.
• Scratchings — a scratched runner changes every other runner's chance and the market percentage. ALWAYS re-pull the card for scratchings before quoting.

Turning prices into probability

• Win market: convert each price to an implied probability (1/price), sum them — the total exceeds 1 by the overround (the book's margin). vig_removal normalises the field to fair probabilities; compare fair prob to the price you can actually get.
• Place markets and each-way pay fractions of the win odds — never compare a win price to a place price as if they're the same market.

Cross-book and exotics

• The best win price is rarely at the same book across runners — quote the book and the price, per runner (best_price).
• For multis/SRM, surface the book's same_race_multi suggestions and their combined price; don't hand-roll combinations or imply a guaranteed collect.

Honesty

Racing is high-variance. Report form, fair probability and the best price; the user decides. Never call a horse a "good thing", a "lock", or a "special".