Thank you for your response. Here are the answers:
1. She is not spayed. We are actually breeding her.
2. She is not technically "jumping" the fence, she is climbing out. We watched her try, so we know how she's doing it. It is made out of wood - about 3-4 ft tall and has very small gaps between each board. So, she is using those gaps to climb out. We will actually be making the fence taller today.
3. Climbing the fence is a newer behavior, but her not coming when she is free is not new...she has always done that. In the house, she responds immediately to the "come" command, but when she is free outside, it is impossible.
4. We only have a small fenced-in space. She lets us know when she needs to go to the bathroom, and we let her out alone. Before she started escaping, she would go out to the bathroom and spend maybe 5-10 minutes sniffing around. Then she would come right to the door and ask to come in.
5. When she escapes, we have been taking treats out and calling to her. If we walk towards her or follow her, it gets worse. But we are near a main road, so we also don't want to just wait around for her to come back.
Our worry isn't so much about how she escapes, that's an easy fix. Our concern is about how to get her to come if/when she does. Not only when she escapes. But we just cannot let her free outside without a leash. We take my brother's dog and Ruby to the park. My brother's dog stays close. We throw her a frisbee and she fetches and plays. Ruby wants so badly to be free with her. We tried it, but as soon as she realizes that it's time to go home or to get back on the leash, she starts the "game" of running from us.
Thanks again,
Misty