4. The system of claim 3 , wherein each of the arcs is associated with an arc weight, and wherein the most probable path is selected based on the arc weight of one or more of the arcs.
4. The system of claim 3 , wherein each of the arcs is associated with an arc weight, and wherein the most probable path is selected based on the arc weight of one or more of the arcs. 5. The system of claim 4 , wherein a path weight is computed for each candidate path among the candidate paths as a sum of the arc weight associated with each of the arcs of the candidate path, and wherein the most probable path is selected based on the path weight of one or more of the candidate paths.