A Dynamic Screening Algorithm for Hierarchical Binary Marketing Data

In many applications of business and marketing analytics, predictive models are fit using hierarchically structured data: common characteristics of products, customers, or web pages are represented as categorical variables, and each category can be split up into multiple subcategories at a lower level of the hierarchy. The model may thus contain hundreds of thousands of binary variables, necessitating the use of variable selection to screen out large numbers of irrelevant or insignificant features. We propose a new dynamic screening method, based on the distance correlation criterion, designed for hierarchical binary data. Our method can screen out large parts of the hierarchy at the higher levels, avoiding the need to explore many lower-level features and greatly reducing the computational cost of screening. The practical potential of the method is demonstrated in a case application on user-brand interaction data from Facebook.