Results 71 to 80 of about 26,892 (218)
The eigenvectors of a combinatorial matrix
Communications Faculty Of Science University of Ankara Series A1Mathematics and Statistics, 2011 In this paper, we derive the eigenvectors of a combinatorial matrix whose eigenvalues studied by Kilic and Stanica. We follow the method of Cooper and Melham since they considered the special case of this matrix.
openaire +2 more sources
Revisiting EWMA in High‐Frequency‐Based Portfolio Optimization: A Comparative Assessment
Journal of Applied Econometrics, EarlyView.ABSTRACT This paper compares the statistical and economic performance of state‐of‐the‐art high‐frequency (HF) based multivariate volatility models with a simpler, widely used alternative, the Exponentially Weighted Moving Average (EWMA) filter. Using over two decades of 100 U.S.
Laura Capera Romero, Anne Opschoor
wiley +1 more source
Journal of Applied Econometrics, EarlyView.ABSTRACT We present four novel tests of equal predictive accuracy and encompassing á Pitarakis (2023, 2025) for factor‐augmented regressions. Factors are estimated using cross‐section averages (CAs) of grouped series and our theoretical findings are empirically relevant: asymptotic normality, robustness to an overspecification of the number of factors,
Alessandro Morico, Ovidijus Stauskas
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Hitting Times in the Binomial Random Graph
Journal of Graph Theory, EarlyView.ABSTRACT Fix k ≥ 2 $k\ge 2$, choose log n n ( k − 1 ) ∕ k ≤ p ≤ 1 − Ω ( log 4 n n ) $\frac{\mathrm{log}n}{{n}^{(k-1)\unicode{x02215}k}}\le p\le 1-{\rm{\Omega }}(\frac{{\mathrm{log}}^{4}n}{n})$, and consider G ~ G ( n , p ) $G\unicode{x0007E}G(n,p)$. For any pair of vertices v , w ∈ V ( G ) $v,w\in V(G)$, we give a simple and precise formula for the ...
Bertille Granet +2 more
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Journal of Magnetic Resonance Imaging, EarlyView.ABSTRACT Background The diffusion tensor image analysis along the perivascular space (DTI‐ALPS) index is an established term, and ongoing research aims to explore underlying mechanisms. Hypothesis DTI‐ALPS measures are influenced by subject‐specific orientational differences of the projection and association fibers. Study Type Prospective.
Dávid Bognár +9 more
wiley +1 more source
Considering spatiotemporal evolutionary information in dynamic multi‐objective optimisation
CAAI Transactions on Intelligence Technology, EarlyView., 2023 Abstract Preserving population diversity and providing knowledge, which are two core tasks in the dynamic multi‐objective optimisation (DMO), are challenging since the sampling space is time‐ and space‐varying. Therefore, the spatiotemporal property of evolutionary information needs to be considered in the DMO.
Qinqin Fan +3 more
wiley +1 more source
Journal of Magnetic Resonance Imaging, EarlyView.ABSTRACT Background Muscle mass decline, associated with strength decline, is a hallmark of aging. Yet, strength decline greatly exceeds mass decline. This indicates that aspects of muscle quality and architecture—not reflected by mass—also influence force generating capacity.
Salim Bin Ghouth +2 more
wiley +1 more source
International Journal of Climatology, EarlyView.Daily bias‐correction aggregated to monthly scale preserves the cross‐correlation between precipitation and temperature better than direct monthly bias‐correction. The Canonical Correlation Analysis (CCA) method outperforms Quantile Regression (QR) and MACA, yielding lower bias and higher accuracy, highlighting its suitability for multivariate climate ...
Chingka Kalai +3 more
wiley +1 more source
Hybrid text mining models for investigative keyword expansion on child sexual abuse in the dark web. [PDF]
PLoS OneKim JG, Kim J.
europepmc +1 more source
Last‐minute coordination: Adapting to demand to support last‐mile operations
Journal of Operations Management, Volume 71, Issue 2, Page 176-194, March 2025.Abstract In the highly competitive e‐commerce industry, customer‐facing warehouses are crucial as the “order penetration points” for e‐commerce last‐mile operations. This research examines how warehouses use last‐minute coordination, an unstructured mechanism, to ensure sufficient inventory at the order penetration points. Previous research has focused
Kedong Chen +3 more
wiley +1 more source