Rajapaksha, R. P. D. D.; Wehigaldeniya, D.S.; Abeykoon, A. M. S. J. P.; Bandaranayaka, R.W. B. M. D. M.
(5th National Conference on Applied Social Statistics (NRCASS) - 2019, Department of Social Statistics, Faculty of Social Sciences, University of Kelaniya, Sri Lanka, 2019)