Table 2 Definitions of Network Measures (Freeman, 1978; Hanneman & Riddle, 2005)

Network level ties

Density is defined as the ratio of ties divided by the number of possible ties. A network’s density may influence the speed at which information diffuses among the nodes/organizations and the extent to which actors have high levels of social capital and/or social constraint

Centralization is an expression of how tightly the network structure is organized around its most central point. The general procedure involved in any measure of graph centralization is to look at the differences between the centrality scores of the most central point and those of all other points. Centralization is the ratio of the actual sum of differences to the maximum possible sum of differences

Node or individual organizational ties

Normalized degree centrality measures adjacent links to or from an organization divided by the possible number of links, expressed as a percentage, and reflects the potential power of direct relationships. These direct links reduce the reliance on intermediaries to access information or resources. More connections are generally considered better than fewer connections

Normalized betweeness centrality measures the extent to which organizations fall between pairs of other organizations on the shortest paths (geodesics) connecting them adjusting for the number of pairs in the network. This measure represents potential mediation or flow of information or resources between organizations in the network. It is used to assess the power in networks, as an organization may control the flow of information and potential resources, thereby increasing dependence of others who are not directly connected in the network

Relationship level ties

Intensity describes the level of interaction between different organizations. In this study, the level of interactions between pairs of organizations was classified as communication (sharing of information between organizations), coordination (organizations implement actions independently, based on shared goals, plans and/or information) and collaboration (organizations jointly create and/or execute actions)

Multiplexity is a measure that describes multiple relationships among the same set of organizations. In this study, four types of working relationships were examined: (a) policy, legislation, strategies and plans; (b) capacity development; (c) knowledge management; and (d) implementation. The multiplexity score ranged from 1 to 4, depending on the number of confirmed working relationships