Question 1

Is there a draw bias at Hamilton?

Accepted Answer

Yes, in places. Across 308 races from 2023-06-01 to 2026-06-09: over 5-6f — moderate: low (inside) favoured (iv 1.19). Check the A/E column before betting it: a bias the market already prices in is not an edge.

Question 2

Does the market already price in the Hamilton draw bias?

Accepted Answer

Not fully. The favoured thirds at Hamilton hold A/E at or above 1 in our window — the bias has not been completely priced away, which is where a draw edge can actually pay.

Question 3

What do IV, A/E and PRB mean?

Accepted Answer

IV (Impact Value) is the group's win rate versus all runners in the same races — 1.00 is neutral. A/E is actual wins versus what de-overrounded Betfair prices expected — below 1 means the market over-bets that group. PRB is the mean percentage of rivals beaten, a finer-grained placing measure.

Draw	Win %	Top-3 %	IV	A/E	PRB	Runs
Low (inside)	13.9% 72 wins	23.9%	1.19 vs course avg	1.12 vs market	65.8%	519
Middle	11.7% 48 wins	18.2%	1.00 vs course avg	0.92 vs market	58.8%	412
High (outside)	9.2% 42 wins	19.6%	0.79 vs course avg	0.91 vs market	59.3%	455

Draw	Win %	Top-3 %	IV	A/E	PRB	Runs
Low (inside)	11% 51 wins	21.6%	0.95 vs course avg	0.86 vs market	62.2%	464
Middle	11.8% 44 wins	18.5%	1.02 vs course avg	0.98 vs market	60.9%	372
High (outside)	12% 50 wins	20.2%	1.04 vs course avg	1.20 vs market	63.2%	416

Hamilton draw bias

5-6f · 163 races

9-12f · 145 races

Common questions

Is there a draw bias at Hamilton?

Does the market already price in the Hamilton draw bias?

What do IV, A/E and PRB mean?

Keep going