The study evaluates various jump tests for high-frequency financial data.
problem Choosing the most effective jump test for high-frequency financial data.
method An extensive evaluation of multiple alternative tests in various scenarios.
result Guidelines for choosing the most suitable test for different settings.
Neural network accuracy improves with denser training samples.
problem Improving neural network accuracy on unseen test samples.
method Bounding empirical training error smoothed across activation regions and using it to discard high-risk test samples.
result Discarding high-risk test samples based on error bounds improves prediction accuracy by up to 20%.
Simplified screening tests for data points in optimization.
problem Discarding irrelevant data points in empirical risk minimization.
method Designing loss functions and regularizing convex losses to induce sparsity, using ellipsoidal approximations.
result Automatic discarding of data samples without losing optimization guarantees.
This work presents a theoretical and empirical evaluation of Anderson-Darling test when the sample size is limited. The test can be applied in order to backtest the risk factors dynamics in the context of Counterparty Credit Risk modelling. We show the limits of such test when backtesting the distributions of an intere…
A heuristic framework tests the multi-manifold hypothesis in empirical data.
problem Overestimation of parameters in global linear models.
method Heuristic multiscale framework using spline-interpolated manifolds.
result Validates the multi-manifold hypothesis in empirical data.
ECCIT improves conditional independence tests by calibrating for miscalibration.
problem Inaccurate frequentist guarantees in CITs, especially in small samples and misspecified models.
method Empirically Calibrated Conditional Independence Tests (ECCIT) that optimize and correct for miscalibration.
result ECCIT achieves valid FDR with higher power than existing calibration strategies.
Develops efficient nonparametric testing with random projections.
problem High computational complexity in nonparametric inference with large data.
method Random projection strategy for kernel ridge regression.
result Achieves testing optimality with minimum number of projections.
Transformer pretraining yields strong EB performance without explicit adaptation.
problem Empirical Bayes problems with unknown test distributions.
method Indirect analysis of pretrained transformer's performance under universal priors.
result Near-optimal regret bound of O ~ ( 1 n ) \widetilde{O}(\frac{1}{n}) O ( n 1 ) for arbitrary test distributions. SGD-trained models' disagreement predicts test error.
problem Estimating test error of deep networks.
method Empirical testing and theoretical analysis of SGD ensembles.
result SGD ensembles' disagreement correlates with test error.
Robust test for distributions under Hellinger distance, simpler than optimal tests.
problem Testing and estimating distributions robustly under Hellinger distance.
method Simple robust hypothesis test with optimal sample complexity, robust to Hellinger distance perturbations.
result Empirically demonstrated robustness and power of the test on canonical distributions.
We propose a class of nonparametric two-sample tests with a cost linear in the sample size. Two tests are given, both based on an ensemble of distances between analytic functions representing each of the distributions. The first test uses smoothed empirical characteristic functions to represent the distributions, the s…
Bayesian optimization methods are evaluated using two metrics.
problem Understanding strengths and weaknesses of Bayesian optimization methods empirically.
method Defined and compared two metrics for Bayesian optimization methods.
result Proposed a ranking mechanism for summarizing performance across different test functions.
The paper explains how neural networks learn less salient frequency components during training.
problem Understanding the grokking phenomenon in neural networks.
method Empirical frequency analysis of training data.
result Neural networks initially learn less salient frequency components of the test data.
We study 'meta-dependence' in conditional independence tests across different empirical distributions.
problem Understanding the breakdown of conditional independence properties in finite data.
method Geometric intuition and information projections to measure meta-dependence between conditional independences.
result We provide a measure of meta-dependence that consolidates findings across synthetic and real-world data.
We describe a novel non-parametric statistical hypothesis test of relative dependence between a source variable and two candidate target variables. Such a test enables us to determine whether one source variable is significantly more dependent on a first target variable or a second. Dependence is measured via the Hilbe…
In the present paper, a fuzzy logic based method is combined with wavelet decomposition to develop a step-by-step dynamic hybrid model for the estimation of financial time series. Empirical tests on fuzzy regression, wavelet decomposition as well as the new hybrid model are conducted on the well known S P 500 SP500 S P 500 index fin…
New measures quantify mutual dependence between multiple random vectors.
problem Measuring mutual dependence between multiple random vectors.
method Proposes three measures based on generalized distance covariance.
result Empirical and simplified empirical measures effectively test mutual independence.
The Restricted Boltzmann Machines (RBM) can be used either as classifiers or as generative models. The quality of the generative RBM is measured through the average log-likelihood on test data. Due to the high computational complexity of evaluating the partition function, exact calculation of test log-likelihood is ver…
The paper finds that faster technological improvement leads to faster diffusion of products.
problem The relationship between technological improvement and innovation diffusion is not well understood.
method Empirical tests across multiple products and technologies.
result Faster diffusion for products based on more rapidly improving technological domains.
A test detects unfairness in machine learning classifiers.
problem Detecting and mitigating algorithmic biases in machine learning.
method Optimal transport theory to quantify and mitigate bias.
result Proposes a statistical test for detecting unfair classifiers.
The paper develops new backtests for Expected Shortfall risk measure.
problem Estimating ES forecasts directly is challenging; existing tests require Value at Risk forecasts.
method Developed a joint regression framework for Value at Risk and Expected Shortfall, providing robust covariance estimators.
result The new backtests significantly outperform existing methods in simulations and empirical applications.
Tests for overfitting in machine learning models.
problem Overfitting in high complexity models.
method Hypothesis test using concentration bounds.
result Valid test for identifying overfitting.
Calibration without labels in multiple testing
problem Interpretable error probabilities in large-scale hypothesis testing
method Constructing pseudo-labels from spacings of ordered p p p -values result Finding that q q q -value can be severely miscalibrated The paper extends hypothesis testing to non-diagonalizable matrices, improving network statistics inference.
problem Testing on non-diagonalizable matrices for network statistics.
method Generalizes Wald and t-tests to non-symmetric matrices, controlling convergence rates.
result Improved inference on network statistics from directed networks.
New tester outperforms existing ones in uniformity testing.
problem Improving uniformity testing accuracy in simulations.
method Introducing a Huber loss-based tester.
result Matches the separation of the collisions tester and has Gaussian-like tails.
Similar models predict similarly, reducing overfitting risk.
problem Excessive reuse of test data in machine learning.
method Proved model similarity mitigates overfitting and provided a generalization bound.
result Model similarity reduces the risk of overfitting, even when accuracy levels suggest otherwise.
A sequential classifier minimizes test samples for binary and multi-class classification.
problem Minimizing test samples for sequential classification with unknown distributions.
method Proposes a classifier for binary and multi-class problems, analyzing error probabilities and extending results.
result Significant advantage over non-sequential classifiers, achieving same exponents without rejection option.
New statistical test for change-point detection using relative entropy.
problem Offline change-point detection using divergence metrics.
method Study of empirical relative entropy distributions, derivation of approximations, introduction of new Berry-Esseen bounds.
result Theoretical and practical validation of relative entropy for change-point detection.
We develop a simple test for deviations from power law tails, which is based on the asymptotic properties of the empirical distribution function. We use this test to answer the question whether great natural disasters, financial crashes or electricity price spikes should be classified as dragon kings or 'only' as black…
Detects model changes in machine learning with empirical difference test.
problem Detect significant model changes between pre-change and post-change parameters.
method Constructs an empirical difference test (EDT) to approximate GLRT, with low computational complexity and false alarm constraint.
result EDT approximates GLRT and provides a method to set threshold for false alarm constraint.
A novel kernel-based test detects equality versus singularity of two probability measures.
problem Detecting equality versus singularity of two probability distributions.
method Combines kernel mean and kernel covariance embeddings to construct a likelihood ratio test statistic.
result The test statistic satisfies a '0/\infty' law, vanishing under the null and diverging under the alternative.
This research designs a data-driven partition to test independence between continuous variables.
problem Testing independence between continuous random variables.
method Empirical log-likelihood statistic and data-driven tree-structured partition.
result Strongly consistent test of independence over probability families.
Since its inception, the modus operandi of multi-task learning (MTL) has been to minimize the task-wise mean of the empirical risks. We introduce a generalized loss-compositional paradigm for MTL that includes a spectrum of formulations as a subfamily. One endpoint of this spectrum is minimax MTL: a new MTL formulation…
The paper improves Fisher-Pitman tests for Poisson mixtures, detecting autism-related genes.
problem Detecting differentially expressed genes between autism and control subjects.
method Nonparametric Poisson mixtures and Fisher-Pitman permutation tests.
result The tests reveal genes missed by common methods, demonstrating rate optimality.
We review the main "omnibus procedures" for goodness-of-fit testing for copulas: tests based on the empirical copula process, on probability integral transformations, on Kendall's dependence function, etc, and some corresponding reductions of dimension techniques. The problems of finding asymptotic distribution-free te…
Study tests adequacy of FARIMA models with uncorrelated but non-independent errors.
problem Testing adequacy of FARIMA models with specific error characteristics.
method Derive asymptotic distributions of residual autocovariances and autocorrelations, propose self-normalization approach.
result Asymptotic distributions of modified portmanteau statistics for weak FARIMA models.
A new method simulates a lazy version of a Markov chain for empirical inference.
problem Estimating and testing unknown Markov chains with limited data.
method Simulates an α-lazy version of an unknown Markov chain, making it ergodic.
result The pseudo spectral gap can be applied to non-ergodic Markov chains.
Paper proposes a differentially private test for joint dependence among random vectors.
problem Detecting joint dependence among sensitive data while maintaining privacy.
method Differentially private permutation methodology for dHSIC test.
result Proposed test attains minimax optimal power across privacy regimes.
Develops a method for reverse stress testing in multivariate scenarios.
problem Reconstructing a multivariate stress scenario from a single exogenous shock.
method Maximizing conditional density under three distributional assumptions.
result Simulated scenarios are economically coherent and reproduce risk-reward asymmetry.
This paper tightens the law of the iterated logarithm for empirical KL_inf, applicable to unbounded data.
problem Developing nonasymptotic concentration bounds for empirical KL_inf with optimal constants and rates.
method Presenting a tight law of the iterated logarithm for empirical KL_inf, applicable to unbounded data.
result A tight law of the iterated logarithm for empirical KL_inf, applicable to unbounded data.
Proposes a method to calibrate data for more accurate linear correlation testing.
problem Inaccurate Pearson's correlation coefficient due to sample size and data non-normality.
method Predictive data calibration using machine learning to condition data on expected linear relationship.
result Calibrated Pearson's correlation coefficient yields a calibrated p-value and r estimate for posterior probability interpretation.
E-C2ST uses E-values for high-dimensional data two-sample tests.
problem Statistical testing for high-dimensional data.
method Combines split likelihood ratio tests and predictive independence tests, using E-values for anytime-valid sequential tests.
result E-C2ST achieves enhanced statistical power by partitioning datasets into multiple batches.
We consider training a deep neural network to generate samples from an unknown distribution given i.i.d. data. We frame learning as an optimization minimizing a two-sample test statistic---informally speaking, a good generator network produces samples that cause a two-sample test to fail to reject the null hypothesis. …
New EB methods handle correlated observations in the Normal Means problem.
problem Handling correlations in the Normal Means problem.
method Developed new EB methods based on Schwartzman's theory.
result New methods compare favorably with other methods in FDR control.
Study evaluates off-policy reinforcement learning methods.
problem Evaluating reinforcement learning policies without direct access to the behavior policy.
method Experimental benchmarking suite with diverse design parameters.
result Guidelines for using off-policy evaluation methods in practice.
The paper explores how machine learning models generalize when the true distribution differs from the training distribution.
problem Understanding generalization beyond the training distribution in machine learning.
method Study through information measures, focusing on mutual information between input samples and representations.
result Bounding the testing gap with high probability using mutual information between input samples and representations.
The paper optimizes A/B tests by balancing lift and cost in large-scale settings.
problem Balancing lift and cost in A/B tests for large-scale experimentation.
method Empirical Bayes approach using a greedy knapsack algorithm to rank experiments based on lift-to-cost ratio, incorporating local false discovery rate (lfdr).
result The proposed method maximizes expected profit while controlling false discovery rate, demonstrating superior performance in large-scale settings.
Develops a test to assess feature significance in neural networks.
problem Assessing the statistical significance of feature variables in neural networks.
method Gradient-based test statistic, asymptotic analysis using nonparametric techniques.
result Tests enable ranking variables by their influence on neural network predictions.