Estimation of Markov Chain via Rank-Constrained Likelihood

Authors: Xudong Li, Mengdi Wang, Anru Zhang

ICML 2018 | Conference PDF | Archive PDF | Plain Text | LLM Run Details

Reproducibility Variable Result LLM Response
Research Type Experimental Experiments show that the proposed estimator achieves better empirical performance than other popular approaches.Finally, the performance of the proposed estimator and algorithm is verified through simulation studies.We compare four estimation procedures, i.e., maximum likelihood estimator (mle), truncated SVD estimator (svd) (Zhang & Wang, 2017), nuclear norm penalized estimator (nu), and our rank-constrained maximum likelihood estimator (rank).
Researcher Affiliation Academia 1Department of Operations Research and Financial Engineering, Princeton University, Sherrerd Hall, Princeton, NJ 08544 2Department of Statistics, University of Wisconsin-Madison, Madison, WI 53706. Correspondence to: Xudong Li <xudongl@princeton.edu>, Mengdi Wang <mengdiw@princeton.edu>, Anru Zhang <anruzhang@stat.wisc.edu>.
Pseudocode Yes Algorithm 1 A PDC algorithm for solving problem (7)Algorithm 2 An s GS-ADMM for solving (D)Algorithm 3 A majorized indefinite-proximal DC algorithm for solving problem (9)
Open Source Code No The paper does not provide any specific links to source code repositories or explicitly state that the code for their methodology is publicly available.
Open Datasets No The paper describes generating synthetic data ('We first generate the rank-r transition matrix as P = UΣVT...Then we simulate a Markov chain trajectory...') for its experiments rather than using a publicly available or open dataset. No access information (link, DOI, citation) is provided for a dataset.
Dataset Splits No The paper does not explicitly provide details about training/validation/test dataset splits. It simulates a single Markov chain trajectory and uses that for estimation, without partitioning into distinct sets for training, validation, and testing.
Hardware Specification No The paper does not provide any specific details about the hardware (e.g., GPU/CPU models, memory) used for running its experiments.
Software Dependencies No The paper does not provide any specific details about ancillary software, such as library names with version numbers, needed to replicate the experiment.
Experiment Setup Yes We first generate the rank-r transition matrix as P = UΣVT , where U, V ℜp r have orthonormal columns and the diagonal matrix Σ = diag(σi) ℜr r with σi > 0 for i = 1, . . . , r. Then we simulate a Markov chain trajectory of length n = C2rp log(p). Here, r = 10, p = 500 and C is a varying constant from 10 to 102.Given c > 0, α 0, and the stopping tolerance η, choose initial point X0 ℜp p.Input: initial point (Ξ0, y0, S0, Z0, X0), penalty parameter σ > 0, maximum iteration number K, and the steplength γ (0, (1 + 5)/2).In the implementation of nuclear norm penalized estimator nu, the penalty parameter is chosen via 5-fold cross-validation.