54 citations · 185 across the 24 of their papers we have counts for
5 papers · 1 filter
Sharp minimax risks and phase transitions in sparse submatrix detection
Subhajit Goswami, Rajarshi Mukherjee
In this paper, we study the minimax risk of detecting a sparse, elevated-mean Gaussian submatrix planted in a larger noisy matrix. When the planted submatrix has size a…
Central Limit Theorem for Gram-Schmidt Random Walk Design
Sabyasachi Chatterjee, Partha S. Dey, Subhajit Goswami
We prove a central limit theorem for the Horvitz-Thompson estimator based on the Gram-Schmidt Walk (GSW) design, recently developed in Harshaw et al.(2022). In particular, we consi…
Spatially Adaptive Online Prediction of Piecewise Regular Functions
Sabyasachi Chatterjee, Subhajit Goswami
We consider the problem of estimating piecewise regular functions in an online setting, i.e., the data arrive sequentially and at any round our task is to predict the value of the…
Adaptive Estimation of Multivariate Piecewise Polynomials and Bounded Variation Functions by Optimal Decision Trees
Sabyasachi Chatterjee, Subhajit Goswami
Proposed by Donoho (1997), Dyadic CART is a nonparametric regression method which computes a globally optimal dyadic decision tree and fits piecewise constant functions in two dime…
New Risk Bounds for 2D Total Variation Denoising
Sabyasachi Chatterjee, Subhajit Goswami
2D Total Variation Denoising (TVD) is a widely used technique for image denoising. It is also an important nonparametric regression method for estimating functions with heterogenou…