Human geography broadly differs from physical geography in that it has a greater focus on studying intangible or abstract patterns surrounding human activity and is more receptive to qualitative research methodologies. It encompasses human, political, cultural, social and economic aspects of the social sciences. While the major focus of human geography is not the physical landscape of the Earth (see physical geography), it is not possible to discuss human geography without going into the physical landscape, on which human activities are being played out and environmental geography is emerging, as an important link between the two. Human geography is methodologically diverse, using both qualitative methods and quantitative methods, including case studies, survey research, statistical analysis and model building, among others. Thematically, human geography may be concerned with an array of human enterprises, from villages and cities, schools, health, commerce and trade, to name a few. The spatial human architecture of a variety of institutions and practices unites these entities within the discipline. For example, a human geographer might be concerned with the geographic patterns of communicable diseases, school performance in rural versus urban school districts or the rise of innovative technology clusters.