I've lived in a rural area for an extended period before and had a lot of experience with dogs. They are territorial. They chase because you are in their territory and they don't recognize what you are. Just keep going, talk to the dog and keep going, once you're beyond their territory they'll stop. Usually they'll stop at the edge of the yard.
I've only known of one in forty years that acted different and he was being trained to hunt. His owner ended up with a very hefty fine when I complained that he was not under control.

Marc