Esther Galbrun and Pauli Miettinen Redescription Mining

In scientific investigations, data oftentimes differ in nature; for instance, they might originate from distinct sources or be cast over separate terminologies. In order to gain insight into the phenomenon of interest, an intuitive first task is to identify the correspondences that exist between these different aspects. This is the motivating principle behind redescription mining, a data analysis task that aims at finding distinct common characterizations of the same objects. In this chapter, we provide the basic definitions of redescription mining, including the data model, query languages, similarity measures, p-value calculations, and methods for pruning redundant redescriptions. We will also briefly cover related data analysis methods and provide a short history of redescription mining research. What is redescription mining? The answer to the eponymous question of this chapter involves some amount of theoretical framework-building: definitions that are used to make other definitions that in turn are used to define yet new concepts that—hopefully—finally yield a coherent and complete definition of redescription mining. That, at least, is the mathematical way to answer the question. A more holistic approach would be to consider how redescription mining relates to other data analysis methods, defining it not by what it is, but through its similarities and dissimilarities. Or, perhaps one could define redescription mining by looking at its evolution, asking how it started and how it became what it is. These are three valid approaches for defining redescription mining, and we will examine them in this chapter. First, though, let us answer the titular question of this chapter with an ostensive definition of redescription mining. 1.1 First Examples of Redescriptions Consider an ecologist who wants to understand what kind of bioclimatic environment different mammal species require. She knows the regions the different mammal species inhabit, and she knows the bioclimatic conditions of those places, such as