A clustering approach for classifying universities in a world sustainability ranking

Sustainability indicators are increasingly recognized as a useful tool to provide policy information in support of environmental, economic or social improvement. Various approaches to sustainability have also been adopted in universities through the introduction of specific rankings. International rankings are an important communication tool that allows the comparison of universities according to combinations of different appropriately weighed parameters. The GreenMetric World University Ranking is the only worldwide ranking of universities that compares environmental sustainability across various campuses. It uses indicators involving education, research and the environment to evaluate the measures undertaken by universities to develop ecological infrastructures and stimulate improvement. The aim of this work is to analyze the individual indicators and categories used in the GreenMetric ranking in detail to verify whether they are, in fact, useful in assessing the sustainability of universities. Through the implementation of the cluster analysis, based on a selection of identified variables, all campuses were classified in homogeneous groups. The results identify four levels of sustainability and show a strong relationship between the rankings of the different categories (setting and infrastructure, energy and climate change, transportation, waste and water conservation and recycling) and specific aspects for assessing institutional policies. These results are useful information to guide universities in the research of key issues on where to invest time and resources to improve the sustainability of their structures and, therefore, their attractiveness.