1. Assistant Professor of Civil Engineering and Director of Construction Engineering and Management Program, Dept. of Civil Engineering, The Catholic Univ. of America, 620 Michigan Ave. NE, Washington, D.C. 20064 (corresponding author).
2. Professor and Executive Director, Pacific Northwest Center for Construction Research and Education, Dept. of Construction Management, Univ. of Washington, 130G Architecture Hall, Box 351610, Seattle, WA 98195.