Exploratory factor analysis of PROMIS-29 V1.0, PROMIS Global Health and the RAND SF-36 from chiropractic responders attending care in a practice-based research network by Joel Alcantara, Andrew Whetten, Cameron Zabriskie, Sharad Jones

“…Methods To uncover latent structures of a large series of measured variables from the PROMIS-29, PROMIS Global Health and RAND SF-36 domains, we defined a factor analysis model represented by the equation $$X = \mu + \Lambda F +\epsilon$$ X = μ + Λ F + ϵ , where $$X = (X_{1} , \ldots ,X_{p} )^{T}$$ X = ( X 1 , … , X p ) T is the matrix of random vectors corresponding to the domains with a mean of $$\mu$$ μ and the covariance matrix $$\Sigma ,$$ Σ , $$\Lambda = \{ l_{jk} \}_{pxm}$$ Λ = { l jk } pxm denotes the matrix of factor loadings, $$F = (F_{1} , \ldots ,F_{m} )^{T}$$ F = ( F 1 , … , F m ) T denotes the matrix of unobserved latent variables that influence the collection of domains and $$\epsilon = (_{1} , \ldots ,_{p} )^{T}$$ ϵ = ( 1 , … , p ) T is the vector of latent error terms. …”
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Retrieval algorithm for the column CO₂ mixing ratio from pulsed multi-wavelength lidar measurements by X. Sun, J. B. Abshire, J. B. Abshire, A. Ramanathan, A. Ramanathan, S. R. Kawa, J. Mao, J. Mao

“…The standard deviation of the retrieved XCO<span class="inline-formula">₂</span> is obtained from the covariance matrix of the fit. The averaging kernel is also provided similarly to that used for passive trace-gas column measurements. …”
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Optimization and operation of integrated homes with photovoltaic battery energy storage systems and power-to-heat coupling by Georg Angenendt, Sebastian Zurmühlen, Fabian Rücker, Hendrik Axelsen, Dirk Uwe Sauer

“…This paper presents optimization results based on the covariance matrix adaptation evolution strategy. The results of the paper indicate that combined operation strategies as well as the optimization of the component sizes strongly influence the economics of photovoltaic battery energy storage systems with power-to-heat coupling. …”
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Variational assimilation of IASI SO₂ plume height and total column retrievals in the 2010 eruption of Eyjafjallajökull using the SILAM v5.3 chemistry transport model by J. Vira, E. Carboni, R. G. Grainger, M. Sofiev

“…The necessary modifications to the observation error covariance matrix are derived.<br><br>Regularization by truncated iteration is investigated as a simple and efficient regularization method for the 4D-Var-based inversion. …”
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Repetibilidade da produção de sementes em clones de guaraná Seed yield repeatability of guarana clones by Firmino José do Nascimento Filho, André Luiz Atroch, Cosme Damião Cruz, Pedro Crescêncio Souza Carneiro

“…Four methods were used for repeatability coefficient estimation: analysis of variance (ANOVA), principal components analysis based on correlation matrix (CPCOR), principal components analysis based on phenotypical variance and covariance matrix (CPCOV), and structural analysis based on correlation matrix (AECOR). …”
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Providing a lean human resources management model by D. Halvachizadeh, Gh. Memarzadeh, N. Mohammadi, H. Doroudi

“…This article has a “descriptive-correlational” methodology of the type of “analysis of variance-covariance matrix”. In other words, the relationship between variables is analyzed based on the purpose of the research. …”
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Mild hypercapnia improves brain tissue oxygen tension but not diffusion limitation in asphyxial cardiac arrest: an experimental study in pigs by Dawei Zhou, Zhimin Li, Shaolan Zhang, Lei Wu, Yiyuan Li, Guangzhi Shi, Jianxin Zhou

“…Generalized mixed model with a compound symmetry covariance matrix was used to compare the time-variables of the two groups. …”
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A Comparative Study on Fetal Heart Rates Estimated from Fetal Phonography and Cardiotocography by Emad A. Ibrahim, Shamsa Al Awar, Zuhur H. Balayah, Leontios J. Hadjileontiadis, Leontios J. Hadjileontiadis, Ahsan H. Khandoker, Ahsan H. Khandoker

“…A novel multi-lag covariance matrix-based eigenvalue decomposition technique was used to separate maternal breathing, fetal heart sounds (fHS) and maternal heart sounds (mHS) from abdominal phonogram signals. …”
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Multifidelity Covariance Estimation Three Ways by Maurais, Aimee Elizabeth

“…Our first positive-definiteness-preserving estimator, referred to as the tangent space or log-linear control variate estimator, constructs a multifidelity covariance estimate by appplying linear control variates to sample covariance matrix logarithms, which are symmetric matrices residing in tangent spaces to the SPD manifold. …”
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Physically constrained maximum likelihood (PCML) mode filtering and its application as a pre-processing method for underwater acoustic communication by Papp, Joseph C

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Asymptotic identification uncertainty of well-separated modes in operational modal analysis with multiple setups by Xie, Yan-Long, Au, Siu-Kui, Li, Binbin

“…Focusing on the case of fixed reference and distinct rovers, analytical study of the eigenvalue properties of mode shape covariance matrix reveals characteristic spatial patterns where principal uncertainty takes place, which can be of local or global nature. …”
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Tracking time-varying properties using quasi time-invariant models with Bayesian dynamic programming by Yang, Yanping, Zhu, Zuo, Au, Siu-Kui

“…Computational issues associated with this new class of models are addressed, e.g., the efficient calculation of posterior most probable value and covariance matrix, and Bayesian evidence in the context of dynamic programming. …”
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Essays on weak identification in high-dimensional models with applications in macroeconomics by Dovì, MS

“…</p> <p>Chapter 5 provides a weak-identification robust IV method for identifying the structural covariance matrix in structural vector autoregressions (SVARs) where data for the reduced-form VAR are available over a longer horizon than for the IV. …”

Robust diagnostics and variable selection procedure based on modified reweighted fast consistent and high breakdown estimator for high dimensional data by Baba, Ishaq Abdullahi

“…Therefore, the robust location and covariance matrix based on the MRFCH is used instead of the classical estimators to tackle these problems. …”
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Explaining the Drivers of Women's Entrepreneurial Opportunities with a Multi-Criteria Group Decision-Making Approach by Ahmad Jafarnajad, Iman Ghasemian Sahebi, Akram Ghasemian Sahebi

“…These results show that the sample variance-covariance matrix is not significantly different from the population variance-covariance matrix and the model fits the experimental data. …”
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Reducing errors in aircraft atmospheric inversion estimates of point-source emissions: the Aliso Canyon natural gas leak as a natural tracer experiment by S M Gourdji, V Yadav, A Karion, K L Mueller, S Conley, T Ryerson, T Nehrkorn, E A Kort

“…An inversion setup using scaled observational wind speed errors in the model-data mismatch covariance matrix is shown to significantly reduce the influence of transport model errors on spatial patterns and estimated leak rates from the inversions. …”
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Identification of miRNA Biomarkers for Diverse Cancer Types Using Statistical Learning Methods at the Whole-Genome Scale by Jnanendra Prasad Sarkar, Jnanendra Prasad Sarkar, Indrajit Saha, Adrian Lancucki, Nimisha Ghosh, Michal Wlasnowolski, Grzegorz Bokota, Grzegorz Bokota, Ashmita Dey, Piotr Lipinski, Dariusz Plewczynski, Dariusz Plewczynski

“…The first part is a feature selection procedure, called the stochastic covariance evolutionary strategy with forward selection (SCES-FS), which is developed by integrating stochastic neighbor embedding (SNE), the covariance matrix adaptation evolutionary strategy (CMA-ES), and classifiers, with the primary objective of selecting biomarkers. …”
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New measurement of the 235U(nth,f) fission yields and development of a Time of Flight line at the LOHENGRIN spectrometer by Houdouin-Quenault M., Sage C., Méplan O., Ramdhane M., Dauvergne D., Gallin-Martel M.L., Muraz J.F., Guillaudin O., Marcatili S., Kessedjian G., Chebboubi A., Serot O., Litaize O., Bernard D., Köster U., Kim Y.H., Mutti P., Smith A.G.

“…New experimental data obtained at the LOHENGRIN spectrometer will be detailed, along with the measurement method and the production of the experimental covariance matrix. The second part will show the development of a Time of Flight (ToF) line in order to improve the background rejection in the mass yield measurements. …”
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Repetibilidade de caracteres agronômicos em Panicum maximum Jacq. Agronomic characters repeatability in Panicum maximum Jacq by Janaina Azevedo Martuscello, Liana Jank, Dilermando Miranda da Fonseca, Cosme Damião Cruz, Daniel de Noronha Figueiredo Vieira da Cunha

“…By the principal component method (based on the covariance matrix), the estimates were always the highest. …”
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Clustering of Marine Oil-Spill Extent Using Sentinel-1 Dual-Polarimetric Scattering Spectrum by Avrodeep Paul, Subhadip Dey, Armando Marino, Gourav Dhar Bhowmick, Avik Bhattacharya

“…The method is based on projecting the <inline-formula><tex-math notation="LaTeX">$2 \times 2$</tex-math></inline-formula> covariance matrix onto distinct random realizations of the normalized scattering configuration. …”
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