6 papers
Sparsity meets correlation in Gaussian sequence model
Subhodh Kotekal, Chao Gao
We study estimation of an -sparse signal in the -dimensional Gaussian sequence model with equicorrelated observations and derive the minimax rate. A new phenomenon emerges fr…
Optimal estimation of the null distribution in large-scale inference
Subhodh Kotekal, Chao Gao
The advent of large-scale inference has spurred reexamination of conventional statistical thinking. In a Gaussian model for many -scores with at most nonnu…
Optimal heteroskedasticity testing in nonparametric regression
Subhodh Kotekal, Soumyabrata Kundu
Heteroskedasticity testing in nonparametric regression is a classic statistical problem with important practical applications, yet fundamental limits are unknown. Adopting a minima…
Minimax Signal Detection in Sparse Additive Models
Subhodh Kotekal, Chao Gao
Sparse additive models are an attractive choice in circumstances calling for modelling flexibility in the face of high dimensionality. We study the signal detection problem and est…
Locally sharp goodness-of-fit testing in sup norm for high-dimensional counts
Subhodh Kotekal, Julien Chhor, Chao Gao
We consider testing the goodness-of-fit of a distribution against alternatives separated in sup norm. We study the twin settings of Poisson-generated count data with a large number…
From optimal score matching to optimal sampling
Zehao Dou, Subhodh Kotekal, Zhehao Xu +1
The recent, impressive advances in algorithmic generation of high-fidelity image, audio, and video are largely due to great successes in score-based diffusion models. A key impleme…