  This paper examines the structure of scientific collaborations in a large
European metropolitan area. It aims to identify strategic coalitions among
organizations in Berlin as a specific case with high institutional and sectoral
diversity. By adopting a global, regional and organization based approach we
provide a quantitative, exploratory and macro view of this diversity. We use
publications data with at least one organization located in Berlin from
1996-2017. We further investigate four members of the Berlin University
Alliance (BUA) through their self-represented research profiles comparing it
with empirical results of OECD disciplines. Using a bipartite network modeling
framework, we are able to move beyond the uncontested trend towards team
science and increasing internationalization. Our results show that BUA members
shape the structure of scientific collaborations in the region. However, they
are not collaborating cohesively in all disciplines. Larger divides exist in
some disciplines e.g., Agricultural Sciences and Humanities. Only Medical and
Health Sciences have cohesive intraregional collaborations which signals the
success of regional cooperation established in 2003. We explain possible
underlying factors shaping the observed trends and sectoral and intra-regional
groupings. A major methodological contribution of this paper is evaluating
coverage and accuracy of different organization name disambiguation techniques.
