Support Recovery in Mixture Models with Sparse Parameters
This addresses support recovery for sparse parameters in mixture models, which is important for high-dimensional data analysis but appears to be an incremental extension of existing mixture model work to sparse settings.
The paper tackles support recovery in high-dimensional mixture models with sparse latent parameters, providing efficient algorithms with logarithmic sample complexity dependence on dimensionality that work across multiple canonical distributions and linear models.
Mixture models are widely used to fit complex and multimodal datasets. In this paper we study mixtures with high dimensional sparse latent parameter vectors and consider the problem of support recovery of those vectors. While parameter learning in mixture models is well-studied, the sparsity constraint remains relatively unexplored. Sparsity of parameter vectors is a natural constraint in variety of settings, and support recovery is a major step towards parameter estimation. We provide efficient algorithms for support recovery that have a logarithmic sample complexity dependence on the dimensionality of the latent space. Our algorithms are quite general, namely they are applicable to 1) mixtures of many different canonical distributions including Uniform, Poisson, Laplace, Gaussians, etc. 2) Mixtures of linear regressions and linear classifiers with Gaussian covariates under different assumptions on the unknown parameters. In most of these settings, our results are the first guarantees on the problem while in the rest, our results provide improvements on existing works.