Datasets:

edushinka
/

line-movement

license: cc-by-4.0
language:
  - en
pretty_name: Line Movement Dataset
size_categories:
  - n<1K
task_categories:
  - tabular-regression
  - tabular-classification
tags:
  - sports-betting
  - line-movement
  - closing-line-value
  - price-discovery
  - gambling-economics
  - tabular
configs:
  - config_name: default
    data_files:
      - betbetter_line_movement_h2h.csv
      - betbetter_line_movement_points.csv
      - betbetter_distance_to_close.csv

Line Movement Dataset — how much betting lines actually move

Aggregate measurements of pre-match betting line movement across 13+ sports and three market types, built from 11.7 million odds snapshots recorded between 29 June and 3 August 2026 across 52 online bookmakers. To our knowledge the first open, multi-sport measurement of line movement magnitude — the canonical public evidence on closing-line value rests on a single operator's blog study.


Source observations	11,740,751 pre-match odds snapshots, ~hourly cadence
Window	29 June – 3 August 2026 (36 days)
Books / competitions	52 bookmakers, 22 competitions
Files	3 aggregate CSVs (sport × market × time-bucket grain)
Licence	CC BY 4.0

Files

`betbetter_line_movement_h2h.csv` — open-to-close probability movement

One row per sport. Head-to-head (two-outcome) markets: the outcome's de-vigged implied probability at the first recorded snapshot vs the last pre-match snapshot, for markets first seen at least 6 hours before start. Columns: observations, mean_lead_hours, mean_abs_move_pp, pct_moved_gt2pp, favourite_signed_drift_pp (positive = favourites shorten toward the close).

`betbetter_line_movement_points.csv` — spread & total line movement

One row per sport × market type. The quoted line itself (points/handicap), first vs last pre-match snapshot: mean_abs_point_move, pct_line_changed, max_point_move.

`betbetter_distance_to_close.csv` — where price discovery happens

One row per sport × time-to-start bucket (7d_plus, 3-7d, 1-3d, 6-24h, 1-6h, under_1h): the mean absolute gap, in probability points, between the de-vigged price at that time and the same outcome's closing price. Cells with fewer than 100 observations are suppressed.

Headline findings

Movement is sport-specific, by an order of magnitude. Mean open-to-close move: UFC/MMA 2.76 pts (53% of outcomes move >2 pts), AFL 2.52, WNBA 1.81 — against MLB 0.60 and ATP-tour tennis ~0.5–0.8.
Price discovery happens 1–7 days out, not at the death. In-season markets sit ~2.2 pts from their close 3–7 days before start, ~1.4 pts at 1–3 days, 0.6 pts at 6–24h and only 0.33 pts in the final 1–6 hours.
Favourites shorten. The opening favourite's probability drifts up toward the close in almost every sport (MMA +0.8 pts, AFL +0.5, WNBA +0.44) — consistent with openers overpricing longshots and the close correcting it.
Spread/total lines move where scoring is high: AFL handicaps move 2.55 pts on average (76% of lines change; max observed 14), WNBA totals 1.69 pts (77% change) — while MLB run lines and NHL puck lines are essentially static.
Pre-season lines barely move: NFL and NHL markets posted months ahead move ~0.3–0.4 pts — lines move when information flows, not with the passage of time.

Construction and caveats

Probabilities are de-vigged (margin removed across the market's outcomes), so movement is price relocation, not margin change. Points (spreads/totals) are the quoted lines themselves.
"Open" = first snapshot in our archive, bounded by the 36-day window — for far-posted markets (NFL) the true open predates the window, so movement figures are floors for those sports. In-season sports (MLB, AFL, WNBA, MMA, tennis, MLS) are fully captured.
Aggregates only: no odds, prices, bookmaker identities, teams, players or event identifiers appear in the data, and no underlying odds feed can be reconstructed from it.
Snapshot cadence is approximately hourly and varies; under_1h cells are thin.

Licence and citation

CC BY 4.0 — free to use, including commercially, with attribution.

Bet Better (2026). Line Movement Dataset: how much betting lines actually move, measured across 11.7M odds snapshots. https://betbetter.world/studies/line-movement

Maintained by Bet Better, which also publishes the Bookmaker Margin Panel, the Market Calibration Dataset, a free sports model API and an open AFL dataset.

18+. Most people lose money gambling. If gambling is causing you harm: gamblinghelponline.org.au.