Extended Data Fig. 10: Standardization of betweenness centrality based on bootstrapping.
From: Dynamics of species-rich predator–prey networks and seasonal alternations of core species
To examine whether each species play disproportionately important topological roles as network cores (hubs) relative to its abundance, bootstrap-standardized betweenness index was calculated for each network node (spider species or prey OTU) in each month. Specifically, the prey repertoire of each spider individual was bootstrap-sampled from the sample-level matrix in each month (1,000 interations). The bootstrapped sample-level matrices were then converted into species-level matrices, subjected to the calculation of betweenness centrality. Bootstrap-standardized betweenness scores were then obtained as \(\frac{{X}_{{observed}}-{Mean}({X}_{{bootstrapped}})}{{SD}({X}_{{bootstrapped}})}\), where Xobserved represented the value calculated based on the original data matrix, and Mean(Xbootstrapped) and SD(Xbootstrapped) were the mean and standard deviation of the values calculated with the bootstrapped matrices, respectively.
