If a path has signs that indicates where the pedestrian and bicyclist should travel along the path, it is recommend that you following what is posted.
On a path that does not have instructional signage and the path has two opposing travel lanes divided evenly by a broken yellow line running down its center, the proper side that a pedestrian should walk on is the far right side of the path and bicycle should ride on the right side of the path. This way, the pedestrian is walking with his or her back to the bicyclist traveling in the same lane. The broken yellow line indicates that bicyclist can use the other lane if needed when passing. This concept is similar to what the markings on a roadway communicate to cars--i.e. if it is a solid yellow line its means no passing and a broken yellow line means passing is legal if passing can be completed safely and without impeding oncoming traffic.
As for strollers and pedestrians walking their animals, they are considered pedestrians and should also walk to the far right side of the path. Bicyclists are encouraged to provide a audible warning, perhaps by bell, horn or voice, as they approach a pedestrian from behind to let pedestrians know that a bicycle is preparing to pass them.