Mining relational databases with multi-view learning

Abstract

Most of today's structured data resides in relational databases where multiple relations are formed by foreign key joins. In recent years, the field of data mining has played a key role in helping humans analyze and explore large databases. Unfortunately, most methods only utilize "flat" data representations. Thus, to apply these single-table data mining techniques, we are forced to incur a computational penalty by first converting the data into this "flat" form. As a result of this transformation, the data not only loses its compact representation but the semantic information present in the relations are reduced or eliminated. In this paper, we describe a classification approach, which addresses this issue by operating directly on relational databases. The approach, called MVC (Multi-View Classification), is based on a multi-view learning framework. In this framework, the target concept is represented in different views and then independently learned using single-table data mining techniques. After constructing multiple classifiers for the target concept in each view, the learners are validated and combined by a meta-learning algorithm. Two methods are employed in the MVC approach, namely (1) target concept propagation and (2) multi-view learning. The propagation method constructs training sets directly from relational databases for use by the multi-view learners. The learning method employs traditional single-table mining techniques to mine data straight from a multi-relational database. Our experiments on benchmark real-world databases show that the MVC method achieves promising results in terms of overall accuracy obtained and run time, when compared with the FOIL and CrossMine learning methods.