Results 91 to 100 of about 1,787,003 (299)

The Effects of Data Imputation on Covariance and Inverse Covariance Matrix Estimation

IEEE Access
Various data analysis techniques and procedures (correlation heatmap, linear discriminant analysis, quadratic discriminant analysis) rely on the estimation of the covariance matrix or its inverse (the precision matrix).
Tuan L. Vo, Quan Huu Do, Thu Nguyen, Pal Halvorsen, Michael A. Riegler, Binh T. Nguyen   +5 more
doaj   +1 more source

Photoluminescence Reshaping via Structural Confinement and Local Density of Optical States Control in Ir(III)‐Doped Biodegradable Metasurfaces

Advanced Materials Technologies, EarlyView.
Phosphorescent biodegradable metasurface showing vibronic selection and spectral photoluminescence narrowing. Anti‐correlation between experimental LDOS and measured lifetimes. ABSTRACT Metasurfaces incorporating phosphorescent emitters offer a route to engineer radiative and vibronic processes beyond chemical design.
Vincenzo Caligiuri, Andrea Smeriglio, Svetlana Siprova, Olga Favale, Francesca Leone, Roberto Termine, Debora Policastro, Alessandra Crispini, Attilio Golemme, Nicolas Godbert, Iolinda Aiello, Antonio De Luca   +11 more
wiley   +1 more source

Portfolio risk measurement: the estimation of the covariance of stock returns [PDF]

A covariance matrix of asset returns plays an important role in modern portfolio analysis and risk management. Despite the recent interests in improving the estimation of a return covariance matrix, there remain many areas for further investigation. This
Liu, Lan
core  

Continual Learning for Multimodal Data Fusion of a Soft Gripper

Advanced Robotics Research, EarlyView.
Models trained on a single data modality often struggle to generalize when exposed to a different modality. This work introduces a continual learning algorithm capable of incrementally learning different data modalities by leveraging both class‐incremental and domain‐incremental learning scenarios in an artificial environment where labeled data is ...
Nilay Kushawaha, Egidio Falotico
wiley   +1 more source

Noise-Adjusted Shrinkage Covariance Estimation in High Dimensions

Axioms
High-dimensional covariance estimation remains a fundamental challenge when the number of variables (p) substantially exceeds the sample size (n).
Esra Pamukçu
doaj   +1 more source

Consensus Formation and Change are Enhanced by Neutrality

Advanced Science, EarlyView.
Neutral agents are shown to enhance both the formation and overturning of consensus in collective decision‐making. A general mathematical model and experiments with locusts and humans reveal that neutrality enables robust consensus via simple interactions and accelerates consensus change by reducing effective population size.
Andrei Sontag, Janina A. Hoffmann, Tim Rogers, Christian A. Yates   +3 more
wiley   +1 more source

HAC estimation in spatial panels [PDF]

, 2012
© 2012 Elsevier B.V. All rights reservedWe propose a HAC estimator for the covariance matrix of the fixed effects estimator in a panel data model with unobserved fixed effects and errors that are both serially and spatially correlated.conomic and Social ...
tosetti e, Tosetti, E, Moscone, F, moscone f, Tosetti E., Moscone F.   +5 more
core   +1 more source

In Situ X‐Ray Tomography and Acoustic Emission Monitoring of Damage Evolution in C/C‐SiC Composites Fabricated by Liquid Silicon Infiltration

Advanced Science, EarlyView.
This study investigates how the internal structure of fiber‐reinforced ceramic composites affects their resistance to damage. By combining 3D X‐ray imaging with acoustic emission monitoring during mechanical testing, it reveals how silicon distribution influences crack formation.
Yang Chen, Renato S. M. Almeida, Stefan Flauder, Guillaume Couégnat, Kamen Tushtev, Jürgen Horvath, Peter Wriggers, Kurosch Rezwan   +7 more
wiley   +1 more source

Mixed-type multivariate response regression with covariance estimation. [PDF]

Stat Med, 2022
Ekvall KO, Molstad AJ.
europepmc   +1 more source

Solid Harmonic Wavelet Bispectrum for Image Analysis

Advanced Science, EarlyView.
The Solid Harmonic Wavelet Bispectrum (SHWB), a rotation‐ and translation‐invariant descriptor that captures higher‐order (phase) correlations in signals, is introduced. Combining wavelet scattering, bispectral analysis, and group theory, SHWB achieves interpretable, data‐efficient representations and demonstrates competitive performance across texture,
Alex Brown, Mathilda Avirett‐Mackenzie, Carolin Villforth, Georgios Exarchakis   +3 more
wiley   +1 more source