Affiliation: | Institute of Statistics and Decision Sciences, Duke University Box 90251, Durham, North Carolina 27708-0251, U.S.A. Developmental Epidemiology Program, Duke University Medical Center Box 3354, Durham, North Carolina 27710, U.S.A. Institute of Statistics and Decision Sciences, Duke University Box 90251, Durham, North Carolina 27708-0251, U.S.A. |