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Enhancing Missing Data Imputation for Migrants Data: A Neutrosophic Set-Based Machine Learning Approach

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Neutrosophic Sets and Systems 2025年 81卷 479-502页

作者： Abdo, Doaa A. Salama, A.A. Abdelmegaly, Alaa A. Mahmoud, Hanan Khadari Mahdi Applied statistics and insurance department faculty of commerce Mansoura university Mansoura Egypt Dept. of Math and Computer Sci. Faculty of Science Port Said Univ. Egypt Higher Institute of Advanced Management Sciences and Computers Al-Buhayrah Egypt Depatrment of applied statistics at the Nile Higher Institute of commercial sciences and Computer Technology in Mansoura Egypt

This study tackles the problem of missing data in migrant datasets by introducing a new framework that combines machine learning techniques with neutrosophic sets. These sets, which can represent uncertainty and ambiguity, are well-suited for managing the complex nature of missing information in sensitive fields like migration research. We test the effectiveness of KNN, SVM, decision tree, random forest, and Ada Boost algorithms on a migrant dataset, comparing their results using different imputation methods (mean/mode, model-based imputer (simple tree), and random values). Our research showed that our proposed approach, which used neutrosophic sets, improved imputation accuracy and strengthened model reliability. Our results underscored the potential of neutrosophic set-based machine learning for addressing missing data issues across various fields. © 2025, University of New Mexico. All rights reserved.

关键词： Adversarial machine learning

ROOTS OF REAL-VALUED ZERO MEAN MAPS: COMPOSITIONS OF LINEAR FUNCTIONALS AND EQUIVARIANT MAPS

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arXiv 2025年

作者： Cantor, Francesca D’Amico, Julia Frick, Florian Myzelev, Eric Dept. Math. Stat. Swarthmore College SwarthmorePA19081 United States Dept. Math & Stat. Reed College PortlandOR97202 United States Dept. Math. Sciences Carnegie Mellon University PittsburghPA15213 United States Dept. Math. University of Pennsylvania PhiladelphiaPA19104 United States

We exhibit the Carathéodory-type result that any point in the convex hull of a closed convex curve in 2d is a convex combination of at most d + 1 points along the curve and extremal results for gaps between zeros of trigonometric polynomials as Borsuk–Ulam-type results for Z/p-equivariant maps from the circle. We develop a geometric-topological framework that gives structural results for the distribution of zeros of certain zero mean maps on the circle and the n-torus. Given an equivariant map γ from a compact metric space X to d and a set F of subsets of X, this framework provides general criteria that guarantee the existence of an A ∈ F such that all compositions of linear functionals with γ have a zero on A. In particular, this seems to be a fruitful perspective to generalize results about common zeros of functions in a Chebyshev space. As a consequence we derive higher precision integration formulas and bounds for the largest geodesic ball in the n-torus where multivariate trigonometric polynomials may stay positive in terms of the size of their *** Codes 41A50, 42A05, 52A20, 54H25 © 2025, CC BY.

关键词： Topology

On the Parallelizability of Approval-Based Committee Rules

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arXiv 2025年

作者： Fitzsimmons, Zack Hassan, Zohair Raza Hemaspaandra, Edith Dept. of Math. and Computer Science College of the Holy Cross WorcesterMA01610 United States Department of Computer Science Rochester Institute of Technology RochesterNY14623 United States

Approval-Based Committee (ABC) rules are an important tool for choosing a fair set of candidates when given the preferences of a collection of voters. Though finding a winning committee for many ABC rules is NP-hard, natural variations for these rules with polynomial-time algorithms exist. The Method of Equal Shares, an important ABC rule with desirable properties, is also computable in polynomial time. However, when working with very large elections, polynomial time is not enough and parallelization may be necessary. We show that computing a winning committee using these ABC rules (including the Method of Equal Shares) is P-hard, thus showing they cannot be parallelized. In contrast, we show that finding a winning committee can be parallelized when the votes are single-peaked or single-crossing for the important ABC rule Chamberlin-Courant. Copyright © 2025, The Authors. All rights reserved.

关键词： Polynomial approximation

Stiffness matrices of graph blow-ups and the d-dimensional algebraic connectivity of complete bipartite graphs

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arXiv 2025年

作者： Jung, Yunseong Lew, Alan Department of Mathematics University of California La Jolla San DiegoCA92093 United States Dept. Math. Sciences Carnegie Mellon University PittsburghPA15213 United States

The d-dimensional algebraic connectivity ad(G) of a graph G = (V, E) is a quantitative measure of its d-dimensional rigidity, defined in terms of the eigenvalues of stiffness matrices associated with different embeddings of the graph into Rd. For a function a: V → N, we denote by G(a) the a-blowup of G, that is, the graph obtained from G by replacing every vertex v ∈ V with an independent set of size a(v). We determine a relation between the stiffness matrix eigenvalues of G(a) and the eigenvalues of certain weighted stiffness matrices associated with the original graph G. This resolves, as a special case, a conjecture of Lew, Nevo, Peled and Raz on the stiffness eigenvalues of balanced blow-ups of the complete graph. As an application, we obtain a lower bound on the d-dimensional algebraic connectivity of complete bipartite graphs. More precisely, we prove the following: Let Kn,m be the complete bipartite graph with sides of size n and m respectively. Then, for every d ≥ 1 there exists cd > 0 such that, for all n, m ≥ d + 1 with n + m ≥ (d+22), ad(Kn,m) ≥ cd · min{n, m}. This bound is tight up to the multiplicative constant. In the special case d = 2, n = m = 3, we obtain the improved bound a2(K3,3) ≥ 2(1 − λ), where λ ≈ 0.6903845 is the unique positive real root of the polynomial 176x4 − 200x3 + 47x2 + 18x − 9, which we conjecture to be tight. Copyright © 2025, The Authors. All rights reserved.

关键词： Stiffness matrix

On the k-volume rigidity of a simplicial complex in Rd

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arXiv 2025年

作者： Lew, Alan Nevo, Eran Peled, Yuval Raz, Orit E. Einstein Institute of Mathematics Hebrew University Jerusalem91904 Israel Dept. Math. Sciences Carnegie Mellon University PittsburghPA15213 United States Institute for Advanced Study PrincetonNJ08540 United States

We define a generic rigidity matroid for k-volumes of a simplicial complex in Rd, and prove that for 2 ≤ k ≤ d−1 it has the same rank as the classical generic d-rigidity matroid on the same vertex set (namely, the case k = 1). This is in contrast with the k = d case, previously studied by Lubetzky and Peled, which presents a different behavior. We conjecture a characterization for the bases of this matroid in terms of d-rigidity of the 1-skeleton of the complex and a combinatorial Hall condition on incidences of edges in k-faces. Copyright © 2025, The Authors. All rights reserved.

关键词： Rigidity

The current state of actuarial science

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AMERICAN math.MATICAL MONTHLY 1996年第7期103卷 552-561页

作者： Minassian, DP Dept. of Math. and Computer Science Butler University Indianapolis IN 46208 United States

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关键词： Actuarial science Bar examinations Credit Research papers Insurance companies Finance Stochastic models Colleges Insurance premiums

Non-euclidean flashlights

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AMERICAN math.MATICAL MONTHLY 1996年第5期103卷 377-385页

作者： Perline, R Dept. of Math. and Computer Science Drexel University Philadelphia PA 19104 United States

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关键词： Ellipses Optical reflection Differential equations Flashlights Hyperbolas Geometric planes math.matical theorems Curves Billiards

Hilbert's 17th problem and the champagne problem

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AMERICAN math.MATICAL MONTHLY 1996年第10期103卷 879-887页

作者： Powers, V Dept. of Math. and Computer Science Emory University Atlanta GA 30322 United States

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MAGNETIC-FIELD CALCULATIONS IN THE BORE OF STRAIGHT SOLENOIDS OF RECTANGULAR CROSS-SECTION

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JOURNAL OF PHYSICS D-APPLIED PHYSICS 1982年第2期15卷 185-191页

作者： CALDWELL, J Dept. of Math. & Computer Studies Sunderland Polytech. Sunderland UK

The problem of optimising the uniformity of the magnetic field produced in the bore of solenoidal coils of rectangular cross-section has already been considered by a number of authors. The aim of this paper is to extend the work of Gibson and Caldwell (1971-2) for a single coil to a number of coils. The usefulness of the work is assessed by drawing comparisons with the work carried out by Garrett (1951, 1967). Numerical results are presented for particular coil parameters.

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