arXivDaily arXiv每日学术速递 周一至周五更新
arXiv周末暂无论文更新,休息一下吧,周末愉快~~

一族演化网络中出现的概率生成函数方程的幂律和对数周期度尾

Power-law and log-periodic degree tails for a family of probability generating function equations arising in evolving networks

Qunqiang Feng, Xiao-Ming Fu, Tianyang Sun

arXiv 2607.12564首次发表:更新:

AI 中文总结

研究一族演化网络模型的概率生成函数方程,通过对超临界高尔顿 - 沃森过程自包含局部分析,确定其极限度分布系数尾,解决了Feng等人的两个猜想,包括幂律阶及乘性周期形式。

AI 中文摘要

对于固定整数\(j\geq1\)和\(0\lt p\lt1\),研究概率生成函数(pgf)方程\((1 + 2p)g(x)=2px^{j}+g(x - px + px^{2})\),\(0\leq x\leq1\),它控制一族演化网络模型的极限度分布\(\{p_k\}\)。\(j = 1\)和\(j = 2\)的情况分别是Feng和Hu的树状快速增长模型以及Feng、Li和Hu的均匀演化网络。证明了对于每个\(j\),方程有唯一pgf解,均值为\(2j\),并精确确定其系数尾。解决了Feng及其合作者的两个猜想:幂律阶\(p_k=\Theta(k^{-1 - \rho})\)及其细化到乘性周期形式\(p_k\sim\Psi_j(\log_{\lambda}k)k^{-1 - \rho}\)。方法是对具有后代律\(1+\mathrm{Bernoulli}(p)\)的超临界高尔顿 - 沃森过程进行自包含局部分析,并在独立几何时间进行检查。主要结果由多智能体系统Eureka获得并经作者验证。

英文摘要

For a fixed integer $j\ge1$ and $0<p<1$, we study the probability generating function (pgf) equation \[ (1+2p)\,g(x)=2p\,x^{j}+g\bigl(x-px+px^{2}\bigr),\qquad 0\le x\le1 , \] which governs the limiting degree distribution $\{p_k\}$ of a family of evolving network models. The cases $j=1$ and $j=2$ are the treelike fast-growth model of Feng and Hu and the homogeneous evolving network of Feng, Li and Hu. We prove that for every $j$ the equation has a unique pgf solution, of mean $2j$, and we determine its coefficient tail exactly: \[ p_k=k^{-1-ρ}\,Ψ_j(\log_λk)+o\bigl(k^{-1-ρ}\bigr), \] where $λ=1+p$, $ρ=\log(1+2p)/\log(1+p)$ is independent of $j$, and $Ψ_j$ is continuous, strictly positive and $1$-periodic, with explicit Fourier coefficients. This resolves two conjectures of Feng and coauthors: (1) the power-law order $p_k=Θ(k^{-1-ρ})$ and (2) its refinement to the multiplicatively periodic form $p_k\simΨ_j(\log_λk)\,k^{-1-ρ}$. The periodic factor is genuinely non-constant for $p$ near $1$, and, for the two network models, for all $p$ outside a discrete set. Consequently, $p_k$ is asymptotic to no constant multiple of $k^{-1-ρ}$. Our method is a self-contained local analysis of the supercritical Galton-Watson process with offspring law $1+\mathrm{Bernoulli}(p)$, inspected at an independent geometric time. This time-changed process solves the equation observed by Feng and coauthors. The main results of this paper were obtained by the multi-agent system Eureka and have subsequently been verified by the authors.

Comments21 pages

论文原文

arXiv 摘要页 · PDF 原文 · HTML 原文

↑