Fig. 3

Graphical representation of the Firm–Firm network, which relates firms with similar bidding patterns. In order to build the network, we only considered the most active firms and edges with a significant Jaccard similarity index. Represented is the giant component with some relevant disconnected components. Nodes in the giant component are colored according to one of the eight major communities (out of 22) identified using the Louvain algorithm (Blondel et al. 2008). The presented partition of the network achieved a modularity of 0.61. North and South categorization of the firms location was used here in a broader sense and should not be confused with the Mesoregions, which we identified with their Portuguese names. For reference, the North includes the Mesoregions of Norte and Noroeste; while the South includes Sul and Centro Sul