Biostatistics Unit, Department of Public Health, Faculty of Medicine and Biomedical Sciences, University of Yaounde 1, Yaounde, Cameroon
Institute for Statistics and Econometrics, University of Goettingen, Goettingen, Germany
Copyright © 2016 Georges Nguefack-Tsague, Walter Zucchini et al. This is
an open access article distributed under the Creative Commons Attribution
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