activity
20242026
collaborators

11 papers

stat.ML2026

Federated Nonparametric Regression with Heterogeneous Clients

Xiaoran Jiang, Anand N. Vidyashankar

Whether a federated predictor benefits an individual client depends on both population heterogeneity and estimation uncertainty. We study this question for Nadaraya--Watson regress…

stat.ML2026

Domain Adaptation with Target Information via Doubly-Anchored Distributionally Robust Optimization

David Kepplinger, Anand N. Vidyashankar

Domain Adaptation (DA) often lacks worst-case guarantees, while Distributionally Robust Optimization (DRO) based only on source data centers its ambiguity set at the source law and…

math.PR2026

Large Deviations for Controlled Branching Processes: Random Slopes, Harmonic Moments, and Transfer Principles

Miguel González, Carmen Minuesa, Inés del Puerto +1

Let \(\{X_n:n\ge0\}\) be a controlled branching process with controls \(ϕ_n\), and let \(N_n=ϕ_n(X_n)\) be its progenitor count. We study large deviations of \(X_{n+1}/N_n\), \(N_n…

stat.ME2026

Robust Estimation of Polychoric Correlation for Complex Survey Designs Using Minimum Divergence Methods

Siqi Wei, David Kepplinger, Anand N. Vidyashankar

Standard maximum likelihood estimation of polychoric correlations is highly sensitive to contamination in survey data, including response errors, interviewer effects, and careless…

stat.ML2025

Hellinger loss function for Generative Adversarial Networks

Giovanni Saraceno, Anand N. Vidyashankar, Claudio Agostinelli

We propose Hellinger-type loss functions for training Generative Adversarial Networks (GANs), motivated by the boundedness, symmetry, and robustness properties of the Hellinger dis…

math.ST2025

Divergence-Minimization for Latent-Structure Models: Monotone Operators, Contraction Guarantees, and Robust Inference

Lei Li, Anand N. Vidyashankar

We develop a divergence-minimization (DM) framework for robust and efficient inference in latent-mixture models. By optimizing a residual-adjusted divergence, the DM approach recov…

math.ST2025

Minimum Hellinger Distance Estimators for Complex Survey Designs

David Kepplinger, Anand N. Vidyashankar

Reliable inference from complex survey samples can be derailed by outliers and high-leverage observations induced by unequal inclusion probabilities and calibration. We develop a m…

math.PR2025

Sharp Large Deviations and Gibbs Conditioning for Threshold Models in Portfolio Credit Risk

Fengnan Deng, Anand N. Vidyashankar, Jeffrey F. Collamore

We obtain sharp large deviation estimates for exceedance probabilities in dependent triangular array threshold models with a diverging number of latent factors. The prefactors quan…

math.ST2025

Ancestral Inference and Learning for Branching Processes in Random Environments

Xiaoran Jiang, Anand N. Vidyashankar

Ancestral inference for branching processes in random environments involves determining the ancestor distribution parameters using the population sizes of descendant generations. I…

math.ST2025

Private Minimum Hellinger Distance Estimation via Hellinger Distance Differential Privacy

Fengnan Deng, Anand N. Vidyashankar

Objective functions based on Hellinger distance yield robust and efficient estimators of model parameters. Motivated by privacy and regulatory requirements encountered in contempor…

stat.ME2024

Grouping predictors via network-wide metrics

Brandon Woosuk Park, Anand N. Vidyashankar, Tucker S. McElroy

When multitudes of features can plausibly be associated with a response, both privacy considerations and model parsimony suggest grouping them to increase the predictive power of a…