Dropping odds in football betting

The opening price is the first price published for an outcome, before most money has been matched. The current price is what is available now. The drop is the percentage fall between the two.

A drop from 2.40 to 2.05 is (2.40 − 2.05) ÷ 2.40 = 14.6%. In implied-probability terms the market moved from 41.7% to 48.8% — a seven-point revision, which is large.

drop % = (opening odds − current odds) / opening odds × 100

Several very different causes produce the same visible movement, which is why a drop must be interpreted rather than obeyed.

• New public information: a confirmed line-up, an injury, a suspension, weather.
• Weight of money: a large volume of matched bets on one side forces the price down.
• Informed money: a smaller stake from a source the market respects can move a price more than a large uninformed one.
• Correction of a mispriced opening line, which says more about the opening price than about the outcome.
• Liability management: a bookmaker balancing its own book, not revising its opinion.

A 12% drop on a market with a few thousand euros matched is close to meaningless — one bet can cause it. The same drop on a deep, heavily traded market is a far stronger statement, because many participants had the chance to take the other side and did not.

Any use of odds movement that ignores matched volume is measuring noise.

By the time you see the shortened price, the information is already in it. The move tells you the market's earlier price was wrong; it does not tell you the new price is wrong in your favour.

There are also failure modes specific to movement data.

• Stale markets: a price left un-updated can appear to move sharply when it finally refreshes.
• Late movement: a drop minutes before kick-off often reflects confirmed team news that is already fully priced.
• Drift back: prices that shorten and then lengthen again usually indicate a temporary imbalance, not information.
• Feed artefacts: a mis-parsed or delayed opening price manufactures a drop that never happened.
• Short prices: a drop into 1.30 leaves no room for error even when the move is genuine.

BetBuddy's selection layer is built on high-volume dropping-odds candidates from the 1X2 market, and it is deliberately explicit that a drop is a market signal, not a probability model.

The production thresholds are: matched volume at or above the configured minimum (30,000 by default), a drop of at least 5% from the opening price, a current price no lower than 1.80 — a hard floor no configuration can lower — and no higher than 5.00, pre-match only.

Candidates are ranked by drop percentage weighted by the logarithm of volume. That score orders candidates; it is never presented as a win probability. Where two outcomes on the same fixture tie on drop and volume, the fixture is flagged for human review instead of the robot guessing.

A candidate is not a bet. Selections lock no earlier than two hours before kick-off, and a locked provisional selection is dropped if the price falls below 1.80 or the drop condition stops holding before the bet is taken.

The useful question is never "how big is the drop?" but "is the price after the drop still long enough to be worth taking?". A 20% drop into 1.45 is a worse proposition than a 6% drop into 2.30 on a market of the same depth.

Whether this approach works is an empirical question, not a claim. Every settled BetBuddy selection is published with its price and result so the record can be checked rather than trusted.