Method apparatus and computer program product for constructing a set of motifs for use in detecting messages of interest

An apparatus for constructing a set of motifs for use in detecting messages of interest in a network of nodes, the apparatus comprising circuitry configured to:

• acquire target data, the target data comprising a set of messages which have been exchanged between nodes in the network, the set of messages including messages of interest:
• acquire control data, the control data comprising a set of messages which have been acquire control data, the control data comprising a set of messages by simulating random exchanges of messages between nodes in the network, such that the control data represents message patterns expected to occur by chance;
• detect a first plurality of motifs within the target data, each of the first plurality of motifs being a repeated pattern of messages appearing within the target data;
• detect a second plurality of motifs within the control data, each of the second plurality of motifs being a repeated pattern of messages appearing within the control data;
• for each of the motifs which have been detected in the target data and each of the motifs which have been detected in the control data, generate a value indicative of a significance of the motif, wherein the value is based on the following:
• a frequency of a motif appearing in the target data, and
• an average frequency of the motif appearing in the control data;
• and
• identify one or more motifs that have a value above a predefined threshold as a motif that represents a message of interest for use in detecting messages of interest from transaction data in the network.

A computer-readable storage device comprising computer executable instructions, that when executed by a processor, cause the processor to perform the following operations:

• acquire target data, the target data comprising a set of messages which have been exchanged between nodes in the network, the set of messages including messages of interest:
• acquire control data, the control data comprising a set of messages which have been acquire control data, the control data comprising a set of messages by simulating random exchanges of messages between nodes in the network, such that the control data represents message patterns expected to occur by chance;
• detect a first plurality of motifs within the target data, each of the first plurality of motifs being a repeated pattern of messages appearing within the target data;
• detect a second plurality of motifs within the control data, each of the second plurality of motifs being a repeated pattern of messages appearing within the control data;
• for each of the motifs which have been detected in the target data and each of the motifs which have been detected in the control data, generate a value indicative of
• a significance of the motif, wherein the value is based on the following:
• a frequency of a motif appearing in the target data, and an average frequency of the motif appearing in the control data;
• and
• identify one or more motifs that have a value above a predefined threshold as a motif that represents a message of interest for use in detecting messages of interest from transaction data in the network.