Derives formulas for swaption prices in HJM model and uses nonparametric fit to identify arbitrage opportunities.
problem Deriving swaption prices in the HJM model and identifying arbitrage opportunities.
method Derives closed form formulas for swaption prices in HJM model and uses nonparametric fit of deterministic forward volatility.
result Demonstrates that the derived formulas and nonparametric fit work well and can identify arbitrage opportunities.
FIT is a fast nonparametric test for conditional independence.
problem Testing conditional independence for high-dimensional data.
method Based on the conditional independence principle, FIT assesses whether additional variables improve predictions.
result FIT is significantly faster and more accurate than existing methods for large datasets.
A test assesses how well data fits a target density function.
problem Measuring how well data fits a target density function without assuming a specific form.
method Stein's method using Reproducing Kernel Hilbert Space functions to construct a divergence measure, estimated via V-statistic.
result The proposed test accurately assesses goodness of fit for various data types and contexts.
A new metric uses nonparametric comparison for fitting parametric distributions.
problem Measuring goodness-of-fit for nonlinear models using maximum likelihood estimation.
method Survival Jensen-Shannon divergence (SJS) and its empirical counterpart (ESJS) for nonparametric comparison. result The ESJS can be used as a measure of goodness-of-fit in maximum likelihood estimation. New tests measure model goodness of fit with interpretable features.
problem Measuring relative goodness of fit between two models.
method Nonparametric, computationally efficient tests producing informative features.
result Test power matches state-of-the-art but is one order faster.
Develops a test for conditional local independence of counting processes.
problem Testing the hypothesis of conditional local independence among continuous time stochastic processes.
method Introduces a new functional parameter, the Local Covariance Measure (LCM), and proposes a test called (X)-LCT using nonparametric estimators and sample splitting or cross-fitting.
result The (X)-LCT test can be controlled uniformly with modest rates, and it works well without restrictive parametric assumptions.
New method tests fit between source and target populations.
problem Testing goodness-of-fit under covariate shift.
method Truncated importance-weighting kernel ridge regression with multiplier bootstrap.
result Valid and sharp confidence sets for regression function.
Paper develops methods for testing fit under shifted covariate distributions.
problem Testing goodness-of-fit under covariate shift with distribution mismatch.
method Truncated importance-weighting kernel ridge regression with multiplier bootstrap.
result Valid and sharp confidence sets for regression function constructed.
A boosting method improves nonparametric density estimation without smoothing assumptions.
problem Overfitting in nonparametric data fitting.
method Introduces a boosting algorithm for univariate nonparametric maximum likelihood estimation.
result Demonstrates the effectiveness of the boosting approach through simulations and real data experiments.
Unified score and distance-based GoF tests for model adequacy.
problem Difficulty in extending score-based GoF tests to nonparametric alternatives.
method Introducing semiparametric kernelized Stein discrepancy (SKSD) test.
result SKSD test is computationally efficient and universally consistent.
Study efficient inference for network quantile causal effects with partial interference.
problem Estimating network causal effects on outcome quantiles with partial interference.
method Developed a nonparametric efficiency theory and a nonparametrically efficient estimator using a three-way cross-fitting procedure.
result Proposed estimator is consistent, asymptotically normal, and allows flexible estimation of nuisance functions.
Kernel Multigrid accelerates Back-fitting for additive Gaussian Processes.
problem Slow convergence of Back-fitting in training additive Gaussian Processes.
method Kernel Packets (KP) and Sparse Gaussian Process Regression (GPR) to enhance Back-fitting.
result Kernel Multigrid reduces the required iterations to O(logn). A new method for signal processing using piecewise convex fitting.
problem Nonparametric function estimation in signal processing.
method Two-stage adaptive estimate with strong smoothing and constrained smoothing spline fit.
result Piecewise convex fitting reduces MSE and accurately estimates change points.
DTL uses Delaunay triangulation for nonparametric function approximation.
problem Functional approximation in high-dimensional feature spaces.
method Delaunay triangulation to partition feature space into simplices, fitting linear models within each.
result DTL's geometrically optimal triangulation improves function approximation accuracy.
Two new tests assess how well conditional models fit data.
problem Assessing goodness of fit for conditional distributions.
method Nonparametric statistical tests using Stein operators.
result Tests are consistent and interpretable.
Proposes a semi-Bayesian nonparametric estimator for MMD in GOF tests and GANs.
problem Challenges in goodness-of-fit testing for intractable models.
method Semi-Bayesian nonparametric estimator of MMD.
result Outperforms frequentist MMD-based methods in false rejection and acceptance rates.
GCMM improves clustering and fits un-synchronized data.
problem Improving clustering performance with copulas.
method Mathematical definition, copula concepts, Expectation Maximum algorithms, nonparametric estimation.
result GCMM outperforms GMM in goodness-of-fit and data analysis.
Gaussian kernel tests are optimal against smooth alternatives.
problem Understanding the statistical properties of nonparametric tests using Gaussian kernels.
method Analysis of Gaussian kernel-based goodness-of-fit, homogeneity, and independence tests.
result Gaussian kernel tests are minimax optimal against smooth alternatives in all three settings.
Efficient nonparametric Bayesian topic model for social media text.
problem Text analytics for social media data.
method Hierarchical Pitman-Yor processes for topic modeling.
result Nonparametric model outperforms existing parametric models.
Sparse-input neural networks handle high-dimensional data with fewer features.
problem Neural networks struggle with high-dimensional data where input features exceed observations.
method Sparse group lasso penalty on first-layer input weights.
result Sparse-input neural networks achieve better performance than existing methods in high-dimensional data with complex interactions.
Deep Heaviside networks are limited but can be improved with connections or linear neurons.
problem Limited expressivity of deep Heaviside networks.
method Including skip connections or linear activation neurons improves expressivity.
result Lower and upper bounds for VC dimensions and approximation rates are derived.
A variable screening procedure via correlation learning was proposed Fan and Lv (2008) to reduce dimensionality in sparse ultra-high dimensional models. Even when the true model is linear, the marginal regression can be highly nonlinear. To address this issue, we further extend the correlation learning to marginal nonp…
The study assesses sensitivity to prior choices in Bayesian nonparametric models.
problem Difficulty in specifying priors for Bayesian nonparametric models.
method Utilizes variational Bayesian methods to assess sensitivity to concentration parameter and stick-breaking distribution.
result Demonstrates how to evaluate sensitivity to prior choices in Dirichlet process mixtures and related models.
Proposes a nonparametric model for dynamic team rankings.
problem Dynamic ranking of distinct teams over time.
method Kernel smoothing for nonparametric estimation in sparse settings.
result Time-varying oracle bounds for estimation and excess risk.
Study compares non-parametric models for predicting medical insurance reimbursement delays.
problem Estimating the time-lapse between medical insurance reimbursement.
method Comparative study of four non-parametric regression models (KNNs, SVMs, Decision Trees, Random Forests) using R-squared metric.
result Each model's performance varies with training data size, feature space, and hyperparameters.
Proposes a nonparametric approach for inferring spike train filters.
problem Modeling neuron information encoding from electrophysiological recordings.
method Gaussian process framework for joint inference of filters and hyperparameters.
result Automatic learning of filter temporal span and stimulus/history filters.
A new test compares latent variable models with kernel methods.
problem Comparing latent variable models with intractable marginal distributions.
method Kernel Stein Test, calibrated threshold, low-dimensional latent structure exploitation.
result Significantly outperforms Maximum Mean Discrepancy test in certain latent structure cases.
Decision stumps accurately screen variables in nonparametric models.
problem Challenges in theoretical properties of tree-based variable importance measures.
method Derive performance guarantees for variable selection using a single-level CART decision tree (decision stump).
result Decision stumps can perform consistent model selection despite being inaccurate for estimation.
Unified framework for DRO and DTA using Bayesian nonparametrics.
problem Combining DRO and DTA under ambiguity.
method Unified framework using DP and HDPs, with outlier robustness.
result Favorable performance in prediction accuracy and stability.
A new test assesses how well observed networks fit a specified ERGM model.
problem Testing the goodness of fit for ERGMs with a single network observation.
method Kernel Stein discrepancy combined with a discrete Stein operator for ERGMs, Monte Carlo simulation.
result The test provides theoretical and practical support for assessing ERGM fit.
Method reconstructs networks from contagion dynamics.
problem Fitting contagion models assumes simple dynamics, ignoring complex contagions.
method Nonparametric method to reconstruct network and dynamics from node states.
result Networks are easier to reconstruct through complex contagions in dense or saturated networks.
Probabilistic method for calibrating local volatility models.
problem Calibration of nonparametric local volatility models.
method Nonparametric approach using Gaussian process prior.
result Better understanding of local volatility uncertainty and dynamics.
New method estimates treatment effects using machine learning.
problem Estimating treatment effects from observational data.
method Double/de-biased machine learning with Neyman-orthogonal scores and cross-fitting.
result Valid inferential statements about treatment effects.
Early stopping improves nonparametric testing optimality.
problem Improving minimax optimal testing in nonparametric settings.
method Applying early stopping to functional gradient descent in RKHS to obtain a Wald-type test.
result Sharp stopping rule for optimal testing in nonparametric settings.
Paper develops fast low-rank approximation for smoothing splines.
problem Computational infeasibility of fitting cubic smoothing splines to large datasets.
method Low-rank approximation using eigensystem truncation.
result The method provides accurate, fast estimates with error bounds.
Deep-HGP uses Bayesian nonparametric approach for complex data regression.
problem Complex data regression with compositional structures.
method Deep Gaussian processes with a squared-exponential kernel, data-driven lengthscale parameters.
result Posterior distribution optimally recovers unknown true regression curve in terms of quadratic loss.
Proposes a lasso variant of MARS for nonparametric regression.
problem Nonparametric regression with MARS.
method Least squares estimation over convex function combinations with a complexity constraint.
result Achieves logarithmic convergence rate in dimensionality.
FlexCodeTS is a flexible time series density estimator.
problem Estimating conditional densities for time series data.
method Nonparametric conditional density estimator based on arbitrary regression methods.
result FlexCodeTS adapts its convergence rate based on the chosen regression method.
Develops an online nonparametric classifier for massive data.
problem Challenges of batch kernel-based nonparametric classifiers in massive data.
method Online principle components analysis to reduce dimensionality, followed by stochastic approximation algorithm for real-time calculation.
result Online classifier provides the best trade-off between accuracy and computation cost.
Proposes a new model to predict irrational customer behavior.
problem Irrational customer behavior in decision-making.
method Nonparametric choice model using decision trees and probability distributions.
result Decision forest model accurately predicts non-rational customer behavior.
Paper studies federated nonparametric testing with privacy constraints, achieving optimal rates and adaptive testing.
problem Federated nonparametric goodness-of-fit testing under distributed differential privacy constraints.
method Establishes matching lower and upper bounds on minimax separation rate, constructs adaptive testing procedure.
result Achieves optimal rates and demonstrates phase transition phenomena in federated testing.
Novel nonparametric method for GLMs improves prediction and inference performance.
problem Improving prediction and inference in GLMs with minimal assumptions.
method Combines binary regression and latent variable formulations, extends parametric versions, introduces new classification statistic.
result Uniformly better prediction and inference performance over parametric formulation, especially with asymmetric data.
A mixture of Gaussians fit to a single curved or heavy-tailed cluster will report that the data contains many clusters. To produce more appropriate clusterings, we introduce a model which warps a latent mixture of Gaussians to produce nonparametric cluster shapes. The possibly low-dimensional latent mixture model allow…
A mixture of Gaussians fit to a single curved or heavy-tailed cluster will report that the data contains many clusters. To produce more appropriate clusterings, we introduce a model which warps a latent mixture of Gaussians to produce nonparametric cluster shapes. The possibly low-dimensional latent mixture model allow…
Optimal tests for goodness of fit and two-sample problems using MMD and KSD.
problem Asymptotically optimal tests for goodness of fit and two-sample problems.
method Maximum Mean Discrepancy (MMD) and Kernel Stein Discrepancy (KSD) based tests.
result Optimal tests achieve the maximum exponential decay rate under specific conditions.
SoftBart improves BART for high-noise modeling in science.
problem High noise in scientific data.
method Soft BART algorithm for Bayesian additive regression trees.
result Improves predictive performance and facilitates larger model integration.
Deep learning method improves regression accuracy.
problem Nonparametric regression challenges.
method Over-parametrized deep neural networks with logistic activation, gradient descent, special topology, random initialization, and data-dependent learning rate.
result Theoretical bound on L2 error and improved finite sample performance. Julia package for Gaussian processes offers fast, flexible, and scalable tools.
problem Modeling complex data sources in various sciences and industries.
method Utilizes Julia's computational benefits for fast, flexible, and user-friendly Gaussian processes.
result Fast, scalable, and user-friendly Gaussian processes package for Julia.