Hanna M. Wallach

  1. An Alternative Prior Process for Nonparametric Bayesian Clustering.

    Authors: Shane T. Jensen, Hanna M. Wallach, Lee Dicker, Katherine A. Heller
    Subjects: Methodology
    Abstract

    Prior distributions play a crucial role in Bayesian approaches to clustering.
    Two commonly-used prior distributions are the Dirichlet and Pitman-Yor
    processes. In this paper, we investigate the predictive probabilities that
    underlie these processes, and the implicit "rich-get-richer" characteristic of
    the resulting partitions. We explore an alternative prior for nonparametric
    Bayesian clustering -- the uniform process -- for applications where the
    "rich-get-richer" property is undesirable.

  2. Learning the Structure of Deep Sparse Graphical Models.

    Authors: Ryan Prescott Adams, Zoubin Ghahramani, Hanna M. Wallach
    Subjects: Machine Learning
    Abstract

    Deep belief networks are a powerful way to model complex probability
    distributions. However, learning the structure of a belief network,
    particularly one with hidden units, is difficult. The Indian buffet process has
    been used as a nonparametric Bayesian prior on the directed structure of a
    belief network with a single infinitely wide hidden layer. In this paper, we
    introduce the cascading Indian buffet process (CIBP), which provides a
    nonparametric prior on the structure of a layered, directed belief network that
    is unbounded in both depth and width, yet allows tractable inference.

Syndicate content