How is a pace map built?
By analysing each horse's recent in-running comments. Phrases like 'made all' or 'led' bucket as front-runner; 'prominent' or 'tracked leaders' as prominent; 'midfield' as mid-division; 'held up in rear' as hold-up. The bucket is taken from the opening clause of each comment, because that describes the rider's early positioning — the most stable signal across runs. Aggregated over 5-6 recent runs, you get the horse's habitual style.