1. Assistant Professor, Dept. of Civil Engineering, Mid-America Transportation Center, Univ. of Nebraska, W348 Nebraska Hall, Lincoln, NE 68588-0531.
2. Traffic Safety and Crash Analysis Engineer, Iowa Dept. of Transportation, Office of Traffic and Safety, 800 Lincoln Way, Ames, IA 50010.
3. Associate Professor, Dept. of Civil and Construction Engineering, Center for Transportation Research and Education, Iowa State Univ., 2901 S. Loop Dr., Ste. 3100, Ames, IA 50010.
4. Assistant Professor, Dept. of Civil and Construction Engineering, Center for Transportation Research and Education, Iowa State Univ., 2901 S. Loop Dr., Ste. 3100, Ames, IA 50010.