Ranking academic impact of GIS research organizations in the United States: a bibliographic network analysis over 20 years

In the United States, geographic information system (GIS) has been widely used and researched in thousands of organizations, including academic institutions, government agencies, and businesses. Few efforts have evaluated how much impact an organization has on the research community. To fill this gap, I established collaboration and citation networks among 2394 US organizations and calculated their impact scores based on quantity, diversity, and spread of scholarly activities. I reported top-ranking organizations between 1992 and 2011 and identified spatio-temporal patterns of GIS growth over the United States. The results are valuable for organizations to assess their strengths and weakness and find a path to broaden the impact.