1. Prof. of Civ. Engrg. and Dir., Inst. of Transp. Studies, Univ. of California, 109 McLaughlin Hall, Berkeley, CA 94720
2. Prof. of Economics, Univ. of California, Berkeley, CA
3. Asst. Prof. of Civ. Engrg., Transp. Res. Ctr., Univ. of Nevada at Las Vegas, 4505 Maryland Parkway, Las Vegas, NV 89154