I lived out in the country and understand about dogs running out after someone. Unfornately, I had a beautiful blue/black chow that 10 minutes after giving it a bath it ran out and got killed in the road.
I personally am very scared of a dog running toward me on a road even if I understand dog behavior and how to avoid conflict. However this behavior needs to be stopped ASAP.
There are several ways of doing this. First get and invisible fence. This will give the dog a shock if it crosses the barrier. It isn't seen and buried under ground. Do let people know you have an invisible fence so they will know they will be okay.
2. Cheap solution. Get some Pet Repellant. These come in bags at Kmart or Walmart in the garden areas. It looks like a fertilizer. Sprinkle this in the areas you want the dog to avoid. It will take a little time but eventually the dog will avoid that area. It does have a strong odor at first but it dies down after a few hours.
I lived in a patio home community where all the property was shared. I used it in the park area to get the dogs from going to the bathroom.
I also got a small decorated fence and put up with a sign notifying repellant was present just in case of children or people with allergies complained.
3. Just tie the dog up on the clothes line with a runner type leash.
The dog also needs to know not all people are friendly. He is looking to make friends.
Hope some of this advice is helpful. good luck