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Support vector machine (SVM) is one of the most studied paradigms in the realm of machine learning for classification and regression problems. It relies on vectorized input data. However, a significant portion of the real-world data exists…

Machine Learning · Computer Science 2023-10-31 Anuradha Kumari , Mushir Akhtar , Rupal Shah , M. Tanveer

The relative performance of competing point forecasts is usually measured in terms of loss or scoring functions. It is widely accepted that these scoring function should be strictly consistent in the sense that the expected score is…

Statistics Theory · Mathematics 2019-04-08 Tobias Fissler , Johanna F. Ziegel

To comply with increasingly stringent international standards in risk management and regulation, several approaches have been developed in the literature for forecasting tail-risk measures such as Value-at-Risk (VaR) and Expected Shortfall…

Risk Management · Quantitative Finance 2026-03-02 Alessandra Amendola , Vincenzo Candila , Antonio Naimoli , Giuseppe Storti

Seismic tomography is a methodology to image the interior of solid or fluid media, and is often used to map properties in the subsurface of the Earth. In order to better interpret the resulting images it is important to assess imaging…

Geophysics · Physics 2020-05-20 Xin Zhang , Andrew Curtis

Estimating the importance of variables is an essential task in modern machine learning. This help to evaluate the goodness of a feature in a given model. Several techniques for estimating the importance of variables have been developed…

Machine Learning · Statistics 2022-08-09 Louis Mozart Kamdem , Ernest Fokoue

Multiscale mixing efficiencies for passive scalar advection are defined in terms of the suppression of variance weighted at various length scales. We consider scalars maintained by temporally steady but spatially inhomogeneous sources,…

Fluid Dynamics · Physics 2007-05-23 Charles R. Doering , Jean-Luc Thiffeault

Variance function estimation in nonparametric regression is considered and the minimax rate of convergence is derived. We are particularly interested in the effect of the unknown mean on the estimation of the variance function. Our results…

Statistics Theory · Mathematics 2008-12-18 Lie Wang , Lawrence D. Brown , T. Tony Cai , Michael Levine

Steering vectors (SVs) have been proposed as an effective approach to adjust language model behaviour at inference time by intervening on intermediate model activations. They have shown promise in terms of improving both capabilities and…

Machine Learning · Computer Science 2025-05-06 Daniel Tan , David Chanin , Aengus Lynch , Dimitrios Kanoulas , Brooks Paige , Adria Garriga-Alonso , Robert Kirk

Economic models produce moment inequalities, which can be used to form tests of the true parameters. Confidence sets (CS) of the true parameters are derived by inverting these tests. However, they often lack analytical expressions,…

Econometrics · Economics 2024-11-14 Lujie Zhou

In this paper, we present new optimization models for Support Vector Machine (SVM), with the aim of separating data points in two or more classes. The classification task is handled by means of nonlinear classifiers induced by kernel…

Optimization and Control · Mathematics 2025-07-15 Francesca Maggioni , Andrea Spinelli

State-space mixed-frequency vector autoregressions are now widely used for nowcasting. Despite their popularity, estimating such models can be computationally intensive, especially for large systems with stochastic volatility. To tackle the…

Econometrics · Economics 2021-12-22 Joshua C. C. Chan , Aubrey Poon , Dan Zhu

This paper explores the estimation and inference of the minimum spanning set (MSS), the smallest subset of risky assets that spans the mean-variance efficient frontier of the full asset set. We establish identification conditions for the…

Portfolio Management · Quantitative Finance 2025-03-19 Zhipeng Liao , Bin Wang , Wenyu Zhou

We analyse a multilevel Monte Carlo method for the approximation of distribution functions of univariate random variables. Since, by assumption, the target distribution is not known explicitly, approximations have to be used. We provide an…

Probability · Mathematics 2017-06-22 Mike B. Giles , Tigran Nagapetyan , Klaus Ritter

Linear Mixed Model (LMM) is a common statistical approach to model the relation between exposure and outcome while capturing individual variability through random effects. However, this model assumes the homogeneity of the error term's…

Methodology · Statistics 2026-01-27 Vincent Jeanselme , Marco Palma , Jessica K Barrett

Support Vector Machine (SVM) is a robust machine learning algorithm with broad applications in classification, regression, and outlier detection. SVM requires tuning the regularization parameter (RP) which controls the model capacity and…

Machine Learning · Statistics 2023-05-18 Mahdi Shamsi , Soosan Beheshti

Spatially-explicit estimates of population density, together with appropriate estimates of uncertainty, are required in many management contexts. Density Surface Models (DSMs) are a two-stage approach for estimating spatially-varying…

Methodology · Statistics 2021-02-25 Mark V Bravington , David L Miller , Sharon L Hedley

In regression models for spatial data, it is often assumed that the marginal effects of covariates on the response are constant over space. In practice, this assumption might often be questionable. In this article, we show how a Gaussian…

Methodology · Statistics 2020-11-13 Jakob A. Dambon , Fabio Sigrist , Reinhard Furrer

We present a method for comparing point forecasts in a region of interest, such as the tails or centre of a variable's range. This method cannot be hedged, in contrast to conditionally selecting events to evaluate and then using a scoring…

Applications · Statistics 2022-02-16 Robert J. Taggart

Expectile regression is a nice tool for investigating conditional distributions beyond the conditional mean. It is well-known that expectiles can be described with the help of the asymmetric least square loss function, and this link makes…

Computation · Statistics 2015-07-15 Muhammad Farooq , Ingo Steinwart

The general relationship between an arbitrary frequency distribution and the expectation value of the frequency distributions of its samples is discussed. A wide set of measurable quantities ("invariant moments") whose expectation value…

Data Analysis, Statistics and Probability · Physics 2015-06-15 Paolo Rossi