Sectional timing methodology

1. Measurement intervals

Sha Tin turf races are recorded at every 200 m; the all-weather track at every 400 m; Happy Valley at every 200 m.

2. Coordinate system

Sectionals are computed backward from the finish line (Last 600 m, Last 400 m, Last 200 m), with forward measurements (First 800 m, First 600 m) reconstructed for symmetry. All values are recorded to 0.01 s precision.

3. Pipeline

1. Pull official sectionals from HKJC's public timing system.
2. Cross-check against RFID / camera-tracked positions; flag clock drift.
3. Run a second QC within 12 hours post-race against finish times and pass-through positions.
4. Anomalies are flagged via quality_flag so clients can choose to include or exclude them.

4. Going allowance

For each meeting Horsorion computes a going allowance grouped by distance × surface × going, regressing toward the long-run mean. The output is an additive correction (seconds) clients can apply directly.

5. Cross-venue comparison

Sha Tin turf, Sha Tin all-weather, and Happy Valley have materially different baselines, turn geometry, and surface friction. Horsorion does not merge raw seconds across venues; instead we publish a Speed Rating derivative for like-for-like comparison.

6. Delivery schema

race_id                varchar  -- "ST-241110-08"
horse_id               int      -- canonical horse id
horse_no               int      -- saddlecloth number
sec_first_800m         numeric  -- seconds from gate to the 800m mark
sec_first_600m         numeric
sec_last_600m          numeric
sec_last_400m          numeric
sec_last_200m          numeric
position_at_800m       int      -- in-field position at that point
position_at_600m       int
position_at_400m       int
going_allowance        numeric  -- additive correction (seconds)
quality_flag           text     -- "OK" / "TIMER_DRIFT" / "MISSING_RFID"