1. Postdoctoral Scholar, Dept. of Civil and Environmental Engineering, Stanford Univ., Stanford, CA 94305 (corresponding author).
2. Senior Financial Modeler, Risk Management Solutions, 7015 Gateway Blvd., Newark, CA 94560-1011.
3. Assistant Professor, Dept. of Civil Engineering and Applied Mechanics, McGill Univ., Montreal, QC H3A2K6, Canada.
4. Professor, Dept. of Civil and Environmental Engineering, Stanford Univ., Stanford, CA 94305.