Skip to yearly menu bar Skip to main content


Talk
in
Workshop: Solving inverse problems with deep networks: New architectures, theoretical foundations, and applications

Robust One-Bit Recovery via ReLU Generative Networks: Improved Statistical Rate and Global Landscape Analysis

Shuang Qiu · Xiaohan Wei · Zhuoran Yang

[ ]
2019 Talk

Abstract: We study the robust one-bit compressed sensing problem whose goal is to design an algorithm that faithfully recovers any sparse target vector θ0Rd \emph{uniformly} from m quantized noisy measurements. Under the assumption that the measurements are sub-Gaussian, to recover any k-sparse θ0 (kd) \emph{uniformly} up to an error ε with high probability, the best known computationally tractable algorithm requires\footnote{Here, an algorithm is ``computationally tractable'' if it has provable convergence guarantees. The notation O~() omits a logarithm factor of ε1.} mO~(klogd/ε4). In this paper, we consider a new framework for the one-bit sensing problem where the sparsity is implicitly enforced via mapping a low dimensional representation x0 through a known n-layer ReLU generative network G:RkRd. Such a framework poses low-dimensional priors on θ0 without a known basis. We propose to recover the target G(x0) via an unconstrained empirical risk minimization (ERM) problem under a much weaker \emph{sub-exponential measurement assumption}. For such a problem, we establish a joint statistical and computational analysis. In particular, we prove that the ERM estimator in this new framework achieves an improved statistical rate of m=O~(knlogd/ϵ2) recovering any G(x0) uniformly up to an error ε. Moreover, from the lens of computation, despite non-convexity, we prove that the objective of our ERM problem has no spurious stationary point, that is, any stationary point is equally good for recovering the true target up to scaling with a certain accuracy. Our analysis sheds some light on the possibility of inverting a deep generative model under partial and quantized measurements, complementing the recent success of using deep generative models for inverse problems.

Live content is unavailable. Log in and register to view live content