The algorithms used to identify nodes can be divided into two classes: deterministic and stochastic algorithms. Deterministic algorithms require the complete information about each node (i.e. either the number or the identity of all connected nodes for each node in the network), and they rank nodes by processing that information by a procedure specific to that algorithm. Target nodes are then chosen by their rank (from high to low). Thus, for a given network structure, deterministic algorithms always give the same result, i.e. they identify the same target nodes (except for random choices when two nodes have exactly the same rank). Stochastic algorithms, on the other hand, do not require such detailed structural information -they identify target nodes by collecting information locally from randomly chosen nodes in the network. These algorithms represent the type of investigationrelated information in actual epidemics. We will now describe a number of deterministic and stochastic algorithms as we have used them in the main text.