Results 101 to 110 of about 6,054,073 (251)

Mixture multigroup structural equation modelling for ordinal data

British Journal of Mathematical and Statistical Psychology, EarlyView.
Abstract Social scientists often compare groups in terms of relations between latent variables (LV) (i.e. structural relations) using Structural Equation Modelling (SEM). LVs are measured indirectly by questionnaires; thus, measurement invariance must be evaluated before comparisons can be made. To efficiently compare many groups, the recently proposed
Andres F. Perez Alonso, Jeroen K. Vermunt, Yves Rosseel, Kim De Roover   +3 more
wiley   +1 more source

A novel hybrid numerical method for delay differential equations with delay-dependent nonlocal condition

Arab Journal of Basic and Applied Sciences
This paper develops a novel hybrid numerical method for the [Formula: see text]-uniform approximation of singularly perturbed second-order delay differential equations subject to delay-dependent nonlocal boundary condition.
Zelal Temel
doaj   +1 more source

On the asymmetry, complexity and predicted data patterns of nontraditional item response theory models

British Journal of Mathematical and Statistical Psychology, EarlyView.
Abstract Traditional item response theory (IRT) models involve symmetric response probability functions, but a developing area of research has focused on asymmetric alternatives. To date, these studies have focused primarily on introducing new asymmetric models, detailing their mathematical formulations, explaining how to interpret their item ...
Hyejin Shim, Wes Bonifay
wiley   +1 more source

Turbo multi-user detection for OFDM/SDMA systems relying on differential evolution aided iterative channel estimation

, 2012
A differential evolution (DE) algorithm aided iterative channel estimation and turbo multi-user detection (MUD) scheme is proposed for multi-user multi-input multiple-output aided orthogonal frequency-division multiplexing/spacedivision multiple-access ...
Chen, Sheng, Mu, Xiaomin, Hanzo, Lajos, Zhang, Jiankang   +3 more
core   +1 more source

Combining differential quadrature method with simulation technique to

, 2008
Nowadays, most of the ordinary differential equations (ODEs) can be solved by modelica-based approaches, such as Matlab/Simulink, Dymola and LabView, which use simulation technique (ST). However, these kinds of approaches restrict the users in the enforcement of conditions at any instant of the time domain.
openaire   +2 more sources

Model fit and parameter uncertainty in amortized variational inference based item response theory

British Journal of Mathematical and Statistical Psychology, EarlyView.
Abstract Amortized variational inference (AVI) has become a popular, computationally efficient alternative to marginal maximum likelihood estimation (MML) for estimating high‐dimensional item response theory models on large datasets. However, currently the AVI framework lacks methods to assess model fit and determine parameter uncertainty.
K. Veldkamp, R. P. P. P. Grasman, R. Debelak, D. Molenaar   +3 more
wiley   +1 more source

An Improved Differential Quadrature Time Element Method

, 2017
A Differential Quadrature Time Element Method (DQTEM) was proposed by the author and co-worker, its drawback is the need of larger storage capacity since the dimension of the coefficients matrix for solution is the product of both spatial degrees of ...
Mingbo Qin, Yufeng Xing, Jing Guo
core   +1 more source

A novel unified variational finite difference (VFD) solution method for optimal control problems

Measurement + Control
This article is aimed to propose a simple yet efficient unified numerical strategy for solving both linear and non-linear optimal control problems. To do so, the general form of quadratic performance index function and nonlinear state equations are ...
Amir Norouzzadeh, Nader Nariman-zadeh, Reza Ansari   +2 more
doaj   +1 more source

Lead isotope evidence for Antarctic Ice Sheet changes in the Weddell Sea sector since the Last Glacial Maximum

Boreas, EarlyView.
The Weddell Sea influences global ocean circulation and sea level through modulating Antarctic Bottom Water formation and Antarctic Ice Sheet discharges, but the history of ice‐sheet dynamics in this region remains poorly constrained due to limited well‐dated geological records.
Huang Huang, Yuanyang Hu, Marcus Gutjahr, Florian Kirsch, Lijuan Lu, Jianjun Zou, Xuefa Shi, Michael Bollen, Jimin Yu, Gerhard Kuhn   +9 more
wiley   +1 more source

Circles of Confidence for Multi‐Label Geometry Completion

Computer Graphics Forum, EarlyView.
Abstract Inside–outside classification is widely used for geometry processing tasks such as surface reconstruction, geometry completion, and calculating signed distance fields. We introduce a new integral formulation of this problem, which assigns confidence scores that points are inside or outside, given incomplete boundary geometry.
Z. Wei, C. Hafner, A. Kalinov, P. Heiss‐Synak, C. Wojtan   +4 more
wiley   +1 more source