Precise Regret Bounds for Log-loss via a Truncated Bayesian Algorithm

Authors: Changlong Wu, Mohsen Heidari, Ananth Grama, Wojciech Szpankowski

NeurIPS 2022 | Conference PDF | Archive PDF | Plain Text | LLM Run Details

Reproducibility Variable Result LLM Response
Research Type Theoretical We study sequential general online regression, known also as sequential probability assignments, under logarithmic loss when compared against a broad class of experts. We obtain tight, often matching, lower and upper bounds for sequential minimax regret, which is defined as the excess loss incurred by the predictor over the best expert in the class. After proving a general upper bound we consider some specific classes of experts from Lipschitz class to bounded Hessian class and derive matching lower and upper bounds with provably optimal constants. Our main contributions are: (i) constructive proofs through a new smooth truncated Bayesian algorithm; (ii) the novel application of global sequential covering in the context of logarithmic loss; (iii) lower and upper bounds with optimal leading constants; and (iv) novel informationtheoretic techniques for the lower bounds.
Researcher Affiliation Academia Changlong Wu1 Mohsen Heidari1,2 Ananth Grama1 Wojciech Szpankowski1 1CSo I, Purdue University 2 Indiana University wuchangl@hawaii.edu, {mheidari,ayg,szpan}@purdue.edu
Pseudocode Yes Algorithm 1 Bayesian predictor, Algorithm 2 Smooth truncated Bayesian predictor
Open Source Code No The paper does not mention releasing any source code or provide links to a code repository.
Open Datasets No The paper is theoretical and focuses on mathematical proofs and algorithms; it does not conduct empirical studies using datasets for training.
Dataset Splits No The paper is theoretical and focuses on mathematical proofs and algorithms; it does not conduct empirical studies using datasets for validation.
Hardware Specification No The paper is theoretical and focuses on mathematical proofs and algorithms; it does not report on computational experiments that would require hardware specifications.
Software Dependencies No The paper is theoretical and focuses on mathematical proofs and algorithms; it does not report on computational experiments that would require software dependencies with specific version numbers.
Experiment Setup No The paper is theoretical and focuses on mathematical proofs and algorithms; it does not report on computational experiments, and thus no experimental setup details like hyperparameters or training settings are provided.