1. Department of Sociology and Anthropology, University of Uyo, Uyo, Nigeria
2. Department of Statistics, Federal University of Technology, Akure, Nigeria
3. Demography and Social Statistics Department, Obafemi Awolowo University, Ile-Ife, Nigeria
4. Demography and Population Studies Programme, Schools of Public Health and Social Sciences, University of the Witwatersrand, Johannesburg, South Africa