1. Lecturer, Dept. of Statistical Science, Univ. College London, London WC1E 6BT, U.K.; formerly, College Lecturer, Dept. of Banking and Finance, Michael Smurfit Graduate School of Business, Univ. College Dublin, Blackrock, Co. Dublin, Republic of Ireland. E-mail: afzal@stats.ucl.ac.uk
2. Staff Scientist, Environmental Energy Technologies Div., Ernest Orlando Lawrence Berkeley National Laboratory, Berkeley, CA 94720. E-mail: c_marnay@lbl.gov
3. Graduate Student Research Assistant, Environmental Energy Technologies Div., Ernest Orlando Lawrence Berkeley National Laboratory, Berkeley, CA 94720. E-mail: rmfirestone@lbl.gov
4. Postdoctoral Fellow, Environmental Energy Technologies Div., Ernest Orlando Lawrence Berkeley National Laboratory, Berkeley, CA 94720. E-mail: nzhou@lbl.gov