Subjects -> STATISTICS (Total: 130 journals)
 Showing 1 - 151 of 151 Journals sorted alphabetically Advances in Complex Systems       (Followers: 10) Advances in Data Analysis and Classification       (Followers: 52) Applied Categorical Structures       (Followers: 4) Argumentation et analyse du discours       (Followers: 7) Asian Journal of Mathematics & Statistics       (Followers: 8) AStA Advances in Statistical Analysis       (Followers: 2) Australian & New Zealand Journal of Statistics       (Followers: 12) Biometrical Journal       (Followers: 9) Biometrics       (Followers: 51) British Journal of Mathematical and Statistical Psychology       (Followers: 17) Building Simulation       (Followers: 2) CHANCE       (Followers: 5) Communications in Statistics - Simulation and Computation       (Followers: 9) Communications in Statistics - Theory and Methods       (Followers: 11) Computational Statistics       (Followers: 15) Computational Statistics & Data Analysis       (Followers: 35) Current Research in Biostatistics       (Followers: 8) Decisions in Economics and Finance       (Followers: 12) Demographic Research       (Followers: 14) Engineering With Computers       (Followers: 5) Environmental and Ecological Statistics       (Followers: 7) ESAIM: Probability and Statistics       (Followers: 4) Extremes       (Followers: 2) Fuzzy Optimization and Decision Making       (Followers: 8) Geneva Papers on Risk and Insurance - Issues and Practice       (Followers: 11) Handbook of Numerical Analysis       (Followers: 5) Handbook of Statistics       (Followers: 7) IEA World Energy Statistics and Balances -       (Followers: 2) International Journal of Computational Economics and Econometrics       (Followers: 6) International Journal of Quality, Statistics, and Reliability       (Followers: 17) International Journal of Stochastic Analysis       (Followers: 2) International Statistical Review       (Followers: 12) Journal of Algebraic Combinatorics       (Followers: 3) Journal of Applied Statistics       (Followers: 20) Journal of Biopharmaceutical Statistics       (Followers: 23) Journal of Business & Economic Statistics       (Followers: 38, SJR: 3.664, CiteScore: 2) Journal of Combinatorial Optimization       (Followers: 7) Journal of Computational & Graphical Statistics       (Followers: 21) Journal of Econometrics       (Followers: 82) Journal of Educational and Behavioral Statistics       (Followers: 7) Journal of Forecasting       (Followers: 19) Journal of Global Optimization       (Followers: 6) Journal of Mathematics and Statistics       (Followers: 6) Journal of Nonparametric Statistics       (Followers: 6) Journal of Probability and Statistics       (Followers: 10) Journal of Risk and Uncertainty       (Followers: 34) Journal of Statistical and Econometric Methods       (Followers: 3) Journal of Statistical Physics       (Followers: 13) Journal of Statistical Planning and Inference       (Followers: 7) Journal of Statistical Software       (Followers: 16, SJR: 13.802, CiteScore: 16) Journal of the American Statistical Association       (Followers: 72, SJR: 3.746, CiteScore: 2) Journal of the Korean Statistical Society Journal of the Royal Statistical Society Series C (Applied Statistics)       (Followers: 36) Journal of the Royal Statistical Society, Series A (Statistics in Society)       (Followers: 28) Journal of the Royal Statistical Society, Series B (Statistical Methodology)       (Followers: 41) Journal of Theoretical Probability       (Followers: 3) Journal of Time Series Analysis       (Followers: 16) Journal of Urbanism: International Research on Placemaking and Urban Sustainability       (Followers: 23) Law, Probability and Risk       (Followers: 6) Lifetime Data Analysis       (Followers: 7) Mathematical Methods of Statistics       (Followers: 4) Measurement Interdisciplinary Research and Perspectives       (Followers: 1) Metrika       (Followers: 4) Monthly Statistics of International Trade - Statistiques mensuelles du commerce international       (Followers: 3) Multivariate Behavioral Research       (Followers: 8) Optimization Letters       (Followers: 2) Optimization Methods and Software       (Followers: 6) Oxford Bulletin of Economics and Statistics       (Followers: 33) Pharmaceutical Statistics       (Followers: 16) Queueing Systems       (Followers: 7) Research Synthesis Methods       (Followers: 7) Review of Economics and Statistics       (Followers: 138) Review of Socionetwork Strategies Risk Management       (Followers: 17) Sankhya A       (Followers: 3) Scandinavian Journal of Statistics       (Followers: 9) Sequential Analysis: Design Methods and Applications Significance       (Followers: 7) Sociological Methods & Research       (Followers: 40) SourceOECD Measuring Globalisation Statistics - SourceOCDE Mesurer la mondialisation - Base de donnees statistiques Stata Journal       (Followers: 8) Statistica Neerlandica       (Followers: 1) Statistical Inference for Stochastic Processes       (Followers: 3) Statistical Methods and Applications       (Followers: 6) Statistical Methods in Medical Research       (Followers: 27) Statistical Modelling       (Followers: 18) Statistical Papers       (Followers: 4) Statistics & Probability Letters       (Followers: 13) Statistics and Computing       (Followers: 13) Statistics and Economics Statistics in Medicine       (Followers: 122) Statistics: A Journal of Theoretical and Applied Statistics       (Followers: 12) Stochastic Models       (Followers: 2) Stochastics An International Journal of Probability and Stochastic Processes: formerly Stochastics and Stochastics Reports       (Followers: 2) Structural and Multidisciplinary Optimization       (Followers: 10) Teaching Statistics       (Followers: 8) Technology Innovations in Statistics Education (TISE)       (Followers: 2) TEST       (Followers: 2) The American Statistician       (Followers: 25) The Canadian Journal of Statistics / La Revue Canadienne de Statistique       (Followers: 10) Wiley Interdisciplinary Reviews - Computational Statistics       (Followers: 1)
Similar Journals
 Journal of Algebraic CombinatoricsJournal Prestige (SJR): 1.199 Citation Impact (citeScore): 1Number of Followers: 3      Hybrid journal (It can contain Open Access articles) ISSN (Print) 1572-9192 - ISSN (Online) 0925-9899 Published by Springer-Verlag  [2469 journals]
• Poincaré polynomial at $$-1$$ - 1 associated with a Young diagram of
three rows

Abstract: In this paper, we give an explicit formula for the Poincaré polynomial $$P_\lambda (x)$$ for the Betti numbers of the Springer fibers over nilpotent elements in $$gl_n(\mathbb {C})$$ of Jordan form $$\lambda =abc$$ with $$a\ge b\ge c\ge 0$$ at $$x=-1$$ . In particular, we introduce $$\lambda$$ -vacillating diagrams and show that $$P_{ab}(-1)$$ is equal to the number of restricted Dyck paths.
PubDate: 2022-05-11

• Partitions of the complete hypergraph $$K_6^3$$ K 6 3 and a
determinant-like function

Abstract: In this paper, we introduce a determinant-like map $$\mathrm{det}^{S^3}$$ and study some of its properties. For this, we define a graded vector space $$\Lambda ^{S^3}_V$$ that has similar properties with the exterior algebra $$\Lambda _V$$ and the exterior GSC-operad $$\Lambda ^{S^2}_V$$ from Staic. When $$\mathrm{dim}(V_2)=2$$ , we show that $$\mathrm{dim}_k(\Lambda ^{S^3}_{V_2}[6])=1$$ , which gives the existence and uniqueness of the map $$\mathrm{det}^{S^3}$$ . We also give an explicit formula for $$\mathrm{det}^{S^3}$$ as a sum over certain 2-partitions of the complete hypergraph $$K_6^3$$ .
PubDate: 2022-05-11

• The facet ideals of matching complexes of line graphs

Abstract: Let $$L_n$$ be a line graph with n edges and $${{\mathcal {F}}}(L_n)$$ be the facet ideal of its matching complex. In this paper, we provide the irreducible decomposition of $${{\mathcal {F}}}(L_n)$$ and some exact formulas for the projective dimension and regularity of $${{\mathcal {F}}}(L_n)$$ .
PubDate: 2022-05-11

• The combinatorics of weight systems and characteristic polynomials of
isolated quasihomogeneous singularities

Abstract: A paper of the first author and Zilke proposed seven combinatorial problems around formulas for the characteristic polynomial and the exponents of an isolated quasihomogeneous singularity. The most important of them was a conjecture on the characteristic polynomial. Here, the conjecture is proved, and some of the other problems are solved, too. In the cases where also an old conjecture of Orlik on the integral monodromy holds, this has implications on the automorphism group of the Milnor lattice. The combinatorics used in the proof of the conjecture consists of tuples of orders on sets $$\{0,1,\ldots ,n\}$$ with special properties and may be of independent interest.
PubDate: 2022-05-09

• Random Schreier graphs and expanders

Abstract: Let the group G act transitively on the finite set $$\Omega$$ , and let $$S \subseteq G$$ be closed under taking inverses. The Schreier graph $$Sch(G \circlearrowleft \Omega ,S)$$ is the graph with vertex set $$\Omega$$ and edge set $$\{ (\omega ,\omega ^s) : \omega \in \Omega , s \in S \}$$ . In this paper, we show that random Schreier graphs on $$C \log \Omega$$ elements exhibit a (two-sided) spectral gap with high probability, magnifying a well-known theorem of Alon and Roichman for Cayley graphs. On the other hand, depending on the particular action of G on $$\Omega$$ , we give a lower bound on the number of elements which are necessary to provide a spectral gap. We use this method to estimate the spectral gap when G is nilpotent.
PubDate: 2022-05-09

• Absolute points of correlations of $$PG(4,q^n)$$ P G ( 4 , q n )

Abstract: Abstract The sets of the absolute points of (possibly degenerate) polarities of a projective space are well known. The sets of the absolute points of (possibly degenerate) correlations, different from polarities, of $$\mathrm {PG}(2,q^n)$$ , have been completely determined by B.C. Kestenband in 11 papers from 1990 to 2014, for non-degenerate correlations and by D’haeseleer and Durante (Electron J Combin 27(2):2–32, 2020) for degenerate correlations. The sets of the absolute points of degenerate correlations, different from degenerate polarities, of a projective space $$\mathrm {PG}(3,q^n)$$ have been classified in (Donati and Durante in J Algebr Comb 54:109–133, 2021). In this paper, we consider the four dimensional case and completely determine the sets of the absolute points of degenerate correlations, different from degenerate polarities, of a projective space $$\mathrm {PG}(4,q^n).$$ As an application, we show that some of these sets are related to the Kantor’s ovoid and to the Tits’ ovoid of $$Q(4,q^n)$$ and hence also to the Tits’ ovoid of $$\mathrm {PG}(3,q^n)$$ .
PubDate: 2022-05-03

• Correction To: Breaking up simplicial homology and subadditivity of
syzygies

Abstract: A correction to this paper has been published: 10.1007/s10801-021-01048-4
PubDate: 2022-05-01

• Classification of bases of twisted affine root supersystems

Abstract: Abstract Following the definition of a root basis of an affine root system, we define a base of the root system R of an affine Lie superalgebra to be a linearly independent subset B of the linear span of R such that $$B\subseteq R$$ and each root can be written as a linear combination of elements of B with integral coefficients such that either all coefficients are nonnegative or all coefficients are non-positive. Characterization and classification of bases of root systems of affine Lie algebras are known in the literature; in fact, up to $$\pm 1$$ -multiple, each base of an affine root system is conjugate with the standard base under the Weyl group action. In the super case, the existence of those self-orthogonal roots which are not orthogonal to at least one other root, makes the situation more complicated. In this work, we give a complete characterization of bases of the root systems of twisted affine Lie superalgerbas with nontrivial odd part. We precisely describe and classify them.
PubDate: 2022-05-01

• On the second largest eigenvalue of some Cayley graphs of the symmetric
group

Abstract: Abstract Let $$S_n$$ and $$A_{n}$$ denote the symmetric and alternating group on the set $$\{1,\ldots ,n\},$$ respectively. In this paper we are interested in the second largest eigenvalue $$\lambda _{2}(\Gamma )$$ of the Cayley graph $$\Gamma =\mathrm{Cay}(G,H)$$ over $$G=S_{n}$$ or $$A_{n}$$ for certain connecting sets H. Let $$1<k\le n$$ and denote the set of all k-cycles in $$S_{n}$$ by C(n, k). For $$H=C(n,n)$$ we prove that $$\lambda _{2}(\Gamma )=(n-2)!$$ (when n is even) and $$\lambda _{2}(\Gamma )=2(n-3)!$$ (when n is odd). Further, for $$H=C(n,n-1)$$ we have $$\lambda _{2}(\Gamma )=3(n-3)(n-5)!$$ (when n is even) and $$\lambda _{2}(\Gamma )=2(n-2)(n-5) !$$ (when n is odd). The case $$H=C(n,3)$$ has been considered in Huang and Huang (J Algebraic Combin 50:99–111, 2019). Let $$1\le r<k<n$$ and let $$C(n,k;r) \subseteq C(n,k)$$ be set of all k-cycles in $$S_{n}$$ which move all the points in the set $$\{1,2,\ldots ,r\}.$$ That is to say, $$g=(i_{1},i_{2},\ldots ,i_{k})(i_{k+1})\dots (i_{n})\in C(n,k;r)$$ if and only if $$\{1,2,\ldots ,r\}\subset \{i_{1},i_{2},\ldots ,i_{k}\}.$$ Our main result concerns $$\lambda _{2}(\Gamma )$$ , where $$\Gamma =\mathrm{Cay}(G,H)$$ with $$H=C(n,k;r)$$ with $$1\le r<k<n$$ when $$G=S_{n}$$ if k is even and $$G=A_{n}$$ if k is odd. Here we observe that \begin{aligned} \lambda _{2}(\Gamma )\ge (k-2)! {n-r \atopwithdelims ()k-r} \frac{1}{n-r} \bi... PubDate: 2022-05-01 • A numerical characterization of the extremal Betti numbers of t-spread strongly stable ideals • Free pre-print version: Loading... Abstract: Abstract Let K be a field and let $$S=K[x_1,\ldots ,x_n]$$ be a standard polynomial ring over a field K. We characterize the extremal Betti numbers, values as well as positions, of a t-spread strongly stable ideal of S. Our approach is constructive. Indeed, given some positive integers $$a_1,\dots ,a_r$$ and some pairs of positive integers $$(k_1,\ell _1),\ldots ,(k_r,\ell _r)$$ , we are able to determine under which conditions there exists a t-spread strongly stable ideal I of S with $$\beta _{k_i, k_i+\ell _i}(I)=a_i$$ , $$i=1, \ldots , r$$ , as extremal Betti numbers, and then to construct it. PubDate: 2022-05-01 • New constructions of Sidon spaces • Free pre-print version: Loading... Abstract: Abstract Sidon spaces can be used to characterize certain multiplicative properties of subspaces. They also have important applications in cyclic subspace codes and Sidon sets. In this paper, we give three new constructions of Sidon spaces. Our results can be applied to cyclic subspace codes. As a result, we obtain some new optimal cyclic subspace codes. PubDate: 2022-05-01 • The power graph of a torsion-free group of nilpotency class 2 • Free pre-print version: Loading... Abstract: Abstract The directed power graph $$\vec {\mathcal {G}}( G)$$ of a group G is the simple digraph with vertex set G in which $$x\rightarrow y$$ if y is a power of x, and the power graph is the underlying simple graph $$\mathcal {G}( G)$$ . In this paper, three versions of the definition of the power graph are discussed, and it is proved that the power graph by any of the three versions of the definition determines the other two up to isomorphism. It is also proved that if G is a torsion-free group of nilpotency class 2 and if H is a group such that $$\mathcal {G}( H)\cong \mathcal {G}( G)$$ , then G and H have isomorphic directed power graphs, which was an open problem proposed by Cameron, Guerra and Jurina [9]. PubDate: 2022-05-01 • Betti numbers of the Springer fibers over nilpotent elements ingl_n({\mathbb {C}})$$g l n ( C ) of Jordan form$$(2^b,1^{a-b})$$( 2 b , 1 a - b ) • Free pre-print version: Loading... Abstract: Abstract In this paper, we compute the generating function for the Betti numbers of the Springer fibers over nilpotent elements in $$gl_n({\mathbb {C}})$$ of Jordan form $$(2^b,1^{a-b})$$ , where $$a\ge b\ge 1$$ . PubDate: 2022-05-01 • On the size of coset unions • Free pre-print version: Loading... Abstract: Abstract Let $$g_1H_1,\ldots ,g_nH_n$$ be cosets of subgroups $$H_1,\ldots ,H_n$$ of a finite group G such that $$g_1H_1\cup \ldots \cup g_nH_n\ne G$$ . We prove that $$g_1H_1\cup \ldots \cup g_nH_n \le \gamma _n G$$ where $$\gamma _n<1$$ is a constant depending only on n. In special cases, we show that $$\gamma _n=(2^n-1)/2^n$$ is the best possible constant with this property and we conjecture that this is generally true. PubDate: 2022-05-01 • Superbinomial coefficients • Free pre-print version: Loading... Abstract: Abstract We investigate several families of polynomials that are related to certain Euler type summation operators. Being integer valued at integral points, they satisfy combinatorial properties and nearby symmetries, due to triangle recursion relations involving squares of polynomials. Some of these interpolate the Delannoy numbers. The results are motivated by and strongly related to our study of irreducible Lie supermodules, where dimension polynomials in many cases show similar features. PubDate: 2022-05-01 • Unlocking the walk matrix of a graph • Free pre-print version: Loading... Abstract: Abstract Let G be a graph of order n, with vertex set $$V=\{v_{1},\dots ,v_{n}\}$$ and adjacency matrix A. For a non-empty set S of vertices let $$\mathrm{e}=(x_{1}, \dots , x_{n})^\mathtt{T}$$ be the characteristic vector of S, that is, $$x_{\ell }=1$$ if $$v_{\ell }\in S$$ and $$x_{\ell }=0$$ otherwise. Then the $$n\times n$$ matrix$$\begin{aligned} W^{S}:=\big [{\mathrm{e}}, A{\mathrm{e}}, A^{2}{\mathrm{e}},\dots ,A^{n-1}{\mathrm{e}}\big ] \end{aligned}$$is the walk matrix of G for S. This term refers to the fact that in $$W^{S}$$ the $$k{\mathrm{th}}$$ entry in the row corresponding to $$v_{\ell }$$ is the number of walks of length $$k-1$$ from $$v_{\ell }$$ to some vertex in S. Let $$\mu _{1},\dots , \mu _{s}$$ be the distinct eigenvalues of A. For given S and characteristic vector $$\mathrm{e}$$ , we re-arrange these eigenvalues in such a way that 1$$\begin{aligned} {\mathrm{SD}}(S)\!:\mathrm{e}=\mathrm{e}_{1}+\mathrm{e}_{2}+\dots +\mathrm{e}_{r} \end{aligned}$$for a certain $$r\le s,$$ where the $$\mathrm{e}_{i}$$ are eigenvectors of A for eigenvalue $$\mu _{i},$$ for all $$1\le i\le r.$$ We refer to (1) as the spectral decomposition of S, or more properly, of its characteristic vector $$\mathrm{e}.$$ We show that the walk matrix $$W^{S}$$ determines the spectral decomposition of S and vice versa. Explicit algorithms are given which establish this correspondence. In particular, we show that the number r of distinct eigenvectors that appear in (1) is equal to the rank of $$W^{S}.$$ Various results can be derived from this theorem. We show that $$W^{S}$$ determines the adjacency matrix of G if $$W^{S}$$ has rank $$\ge n-1.$$ Another application ... PubDate: 2022-05-01 • On the depth of binomial edge ideals of graphs • Free pre-print version: Loading... Abstract: Abstract Let G be a graph on the vertex set [n] and $$J_G$$ the associated binomial edge ideal in the polynomial ring $$S=\mathbb {K}[x_1,\ldots ,x_n,y_1,\ldots ,y_n]$$ . In this paper, we investigate the depth of binomial edge ideals. More precisely, we first establish a combinatorial lower bound for the depth of $$S/J_G$$ based on some graphical invariants of G. Next, we combinatorially characterize all binomial edge ideals $$J_G$$ with $$\mathrm {depth} S/J_G=5$$ . To achieve this goal, we associate a new poset $$\mathscr {M}_G$$ with the binomial edge ideal of G and then elaborate some topological properties of certain subposets of $$\mathscr {M}_G$$ in order to compute some local cohomology modules of $$S/J_G$$ . PubDate: 2022-05-01 • A classification of flag-transitive block designs • Free pre-print version: Loading... Abstract: Abstract In this article, we investigate 2- $$(v,k,\lambda )$$ designs with $$\gcd (r,\lambda )=1$$ admitting flag-transitive automorphism groups G. We prove that if G is an almost simple group, then such a design belongs to one of the eight infinite families of 2-designs or it is one of the eleven well-known examples. We describe all these examples of designs. We, in particular, prove that if $${\mathcal {D}}$$ is a symmetric $$(v,k,\lambda )$$ design with $$\gcd (k,\lambda )=1$$ admitting a flag-transitive automorphism group G, then either $$G\leqslant \mathrm {A}\Gamma \mathrm {L}_{1}(q)$$ for some odd prime power q, or $${\mathcal {D}}$$ is the point-hyperplane design or the unique Hadamard design with parameters (11, 5, 2). PubDate: 2022-05-01 • Classification of the non-trivial 2-$$(v,k,\lambda )$$( v , k , λ ) designs, with$$ (r,\lambda )=1$$( r , λ ) = 1 and$$\lambda >1 λ
> 1 , admitting a non-solvable flag-transitive automorphism group of
affine type

Abstract: Abstract Non-trivial 2- $$(v,k,\lambda )$$ designs, with $$(r,\lambda )=1$$ and $$\lambda >1$$ , admitting a non-solvable flag-transitive automorphism group of affine type are classified.
PubDate: 2022-05-01

• Presentations for vertex-transitive graphs

Abstract: Abstract We generalise the standard constructions of a Cayley graph in terms of a group presentation by allowing some vertices to obey different relators than others. The resulting notion of presentation allows us to represent every vertex-transitive graph.
PubDate: 2022-05-01

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