Fig. 4

Characterization of the ten largest communities by the diversity of bids done by region and type. Panel a shows the distribution of bids within each community by mesoregion (left) and contract/tender type (right). For each community we compute the Simpson’s diversity index (\(\lambda _{\mathrm{reg}}\) and \(\lambda _{\mathrm{serv}}\)). The full and official names of the mesoregions are: Jaguaribe; Noroeste Cearense (Noroeste); Metropolitana de Fortaleza (Metropolitana); Sul Cearense (Sul); Norte Cearense (Norte); Centro-Sul Cearense (Centrol Sul); and Sertoes Cearenses (Sertão). We use simplified references to these names for visualization purposes. Panel b compares communities by their diversity of contracts in terms of regional span and type. Note that in panel a we only show results for the ten largest communities, which are representative of the results. Communities not identified by a color code in Fig. 2 are shown in gray in panel b, in the particular community \(C_{14}\) corresponds to the gray clique easily identifiable in the bottom left of the network in Fig. 3