A weighted clustering of population pyramids for the world's countries, 1996, 2001, 2006.

This paper presents clusters of the world's countries obtained by a novel weighted clustering method. The approach is based on data representations with symbolic descriptions of age-sex structures. To obtain clusters with similar descriptions, a weighted clustering method is used which is suitable for data described with discrete distributions. In contrast to the classical approach, this method allows the population of each sex to be included in the clustering process, thereby obtaining a representative age-sex structure corresponding to all the countries contained in the cluster. Observing the data over time reveals clusters of countries with similar changes in their population age-sex distributions. The resulting population pyramids are presented for 1996, 2001, and 2006.