Degree distributions of growing networks

The in-degree and out-degree distributions-of a growing network model are d etermined. The in-degree is the number of incoming links to a given node (a nd vice versa for out-degree). The network is built by (i) creation of new nodes which each immediately attach to a preexisting node, and (ii) creatio n of new links between preexisting nodes. This process naturally generates correlated in-degree and out-degree distributions. When the node and link c reation rates are linear functions of node degree, these distributions exhi bit distinct power-law forms. By tuning the parameters in these rates to re asonable values, exponents which agree with those of the web graph are obta ined.