TRAINER JOCKEY COMBO

Calculated from the trainer-jockey combination win count and starts count. A pairing with a documented history of winning together brings cumulative advantages: the jockey understands the trainer's instructions and horse-specific tendencies, and the trainer books this rider when confident in the horse. The HOT_COMBO_LONGSHOT notable is the market-value extension of this angle — TRAINER_JOCKEY_COMBO fires on the partnership itself, regardless of odds, while HOT_COMBO_LONGSHOT adds the requirement that the public is undervaluing the pairing.