Improved iterative resource allocation (IIRA) method
The
improved Iterative Resource Allocation
(IIRA) method is an extension of the iterative resource allocation (IRA) method that incorporates both neighbor centrality and the spreading rate to evaluate node influence [2]. In IIRA, each node \(i\) is initially assigned a resource \(I_i(0)\), which is iteratively distributed to its neighbors according to their centrality and the spreading rate \(β\). After a sufficient number of iterations \(t\), the resource \(I_i(t)\) of each node approaches a steady state, and the final resource values are used to identify influential nodes.
The diffusion process can be formalized using the \(N \times N\) stochastic matrix \(P\), with entries
\[
p_{ij} = \left( 1 - (1-β)^{d_i} \right) \frac{a_{ij} c_i}{\sum_{k=1}^N a_{ik} c_k},
\]
where \(a_{ij}\) is the adjacency matrix, \(c_i\) represents a chosen centrality of node \(i\), and \(d_i\) is its degree. Zhong et al. [2] set the spreading rate \(β = 0.2\) and the number of iterations \(t = 50\), demonstrating that IIRA computed using closeness centrality provides more accurate identification of influential nodes than the version based on eigenvector centrality.