1. Visiting Assistant Professor of Civil Engineering and Research Program Manager of the Center for Road Safety, Dept. of Civil Engineering, Purdue Univ., 550 Stadium Mall Dr., West Lafayette, IN 47907 (corresponding author).
2. Research Scientist, Dept. of Civil Engineering, Purdue Univ., 550 Stadium Mall Dr., West Lafayette, IN 47907.
3. Assistant Professor of Civil, Construction, and Environmental Engineering, Iowa State Univ., 404 Town Engineering Building, Ames, IA 50011.
4. Charles Pankow Professor of Civil Engineering, Purdue Univ., 550 Stadium Mall Dr., West Lafayette, IN 47907.
5. Edgar B. and Hedwig M. Olson Distinguished Professor of Civil Engineering and Director of Joint Transportation Research Program, Purdue Univ., 550 Stadium Mall Dr., West Lafayette, IN 47907.