Again, keep the elements of class, wind and track condition in mind. At any given track, there is a broad range of talent. For instance, if you note that a leading jockey has been taken off his regular mount and switched to another, you could have a better chance of a winning wager on his new mount. As with jockeys, any given track will have a broad range of trainers, with varying degrees of expertise and experience. Try to keep track of a trainer's ability with different classes or ages of horses.
Some trainers are better with claiming horses, while others concentrate on stakes performers.
A listing of horse's sire, dam and dam's sire. As a general rule, pedigree has a significant influence on a horse's natural ability to run. Keep note of the leading sires and dams as well as breeders and owners when considering class.