Mining generalized temporal patterns based on fuzzy counting

Event-based sequences are a kind of pattern based on temporal associations with two essential characteristics: they are syntactically simple and have a great expressive power. For this reason, event-based sequence mining is an interesting solution to the problem of knowledge discovery in dynamic domains, mainly characterized by a time-varying nature. The inter-transactional model has led to the design of algorithms aimed to obtain this sort of patterns from time-stamped datasets. These algorithms extend the well-known Apriori algorithm, by explicitly adding the temporal context where associations among frequent events occurs. This leads to the possibility of extracting a larger number of patterns with a potential interest in decision making. However, its usefulness is diminished in those datasets where the characteristics of variability and uncertainty are present, which is a common issue in real domains. This is due to the rigidity of the counting method, which uses an exact measure of distance between temporal events. As a solution, we propose a generalization of the temporal mining process, which implies a relaxation of the counting method including the concept of approximate temporal distance between events. In particular, in this paper we present an algorithm, called TSETfuzzy-Miner, which incorporates a fuzzy-based counting technique in order to extract general, flexible, and practical temporal patterns taking into account the particular characteristics of real domains.

► We propose a fuzzy set-based method for mining generalized event-based temporal patterns.
► The algorithm uses a flexible measure of distance between events.
► The counting method is based on a user-defined fuzzy set associated with the linguistic term approximately equal to.
► The algorithm extracts general, flexible, and practical patterns from real datasets where uncertainty and variability are presented.
► We have carried out a series of experiments to assess and characterize the algorithm with both, synthetic and real datasets.