Hiding Sequences

The process of discovering relevant patterns holding in a database, was first indicated as a threat to database security by O´ Leary in [20]. Since then, many different approaches for knowledge hiding have emerged over the years, mainly in the context of association rules and frequent itemsets mining. Following many real-world data and applications demands, in this paper we shift, the problem of knowledge hiding to contexts where both the data arid the extracted knowledge have a sequential structure. We provide problem statement, some theoretical issues including NP-hardness of the problem, a polynomial sanitization algorithm and an experimental evaluation. Finally we discuss possible extensions that will allow to use this work as a basic building block for more complex kinds of patterns and applications.