Locating names on vertices of a transaction network

This paper deals with the problem of identifying names of unknown subjects located on vertices of a network which is previously established among subjects. The only available information is the knowledge of the names of some subjects in the network, and certain records of previous observations of transactions between all pairs of subjects. Such records offer us information about the frequency or intensity of these transactions. The aim is to find the more suitable identification of the unknown subjects taking into account the information about the frequency of transactions among subjects. It is proved that the problem is NP-hard. A heuristic approach is proposed for solving it and its performance is numerically illustrated.