论文标题
中央限制定理通过几个变量中的分析组合制剂
Central Limit Theorems via Analytic Combinatorics in Several Variables
论文作者
论文摘要
分析组合学领域致力于创建有效的技术来研究组合对象的大规模行为。尽管分析组合学的经典结果主要与单变量产生函数有关,但在过去的二十年中,已经开发了几个变量(ACSV)的分析组合理论来研究多变量序列的渐近行为。在这项工作中,我们从概率的角度调查了ACSV,说明其最先进的方法如何提供有效的算法以得出极限定理,并将结果与过去的工作得出的组合限制定理进行比较。使用ACSV的结果,我们提供了一个可以自动计算(并严格验证)限制各种组合生成函数的定理的SageMath软件包。为了说明所涉及的技术,我们还为组合类别的家族建立了明确的局部中央限制定理,其生成函数在跟踪每个参数的变量中是线性的。该结果涵盖的应用程序包括在某些限制排列中的周期分布(证明了Chung等人最近工作中的猜想的限制定理),整数组成和$ n $颜色的组成,具有不同的限制和值。在任意维度中建立这些显式结果的关键是一个有趣的符号决定因素,我们通过猜想来计算,然后证明适当的$ lu $ factorization。我们希望这项工作为读者提供蓝图,以应用ACSV的强大工具来证明自己的工作中的中心限制定理,从而使它们更容易成为组合主义者,概率主义者和相邻领域的人。
The field of analytic combinatorics is dedicated to the creation of effective techniques to study the large-scale behaviour of combinatorial objects. Although classical results in analytic combinatorics are mainly concerned with univariate generating functions, over the last two decades a theory of analytic combinatorics in several variables (ACSV) has been developed to study the asymptotic behaviour of multivariate sequences. In this work we survey ACSV from a probabilistic perspective, illustrating how its most advanced methods provide efficient algorithms to derive limit theorems, and comparing the results to past work deriving combinatorial limit theorems. Using the results of ACSV, we provide a SageMath package that can automatically compute (and rigorously verify) limit theorems for a large variety of combinatorial generating functions. To illustrate the techniques involved, we also establish explicit local central limit theorems for a family of combinatorial classes whose generating functions are linear in the variables tracking each parameter. Applications covered by this result include the distribution of cycles in certain restricted permutations (proving a limit theorem stated as a conjecture in recent work of Chung et al.), integer compositions, and $n$-colour compositions with varying restrictions and values tracked. Key to establishing these explicit results in arbitrary dimension is an interesting symbolic determinant, which we compute by conjecturing and then proving an appropriate $LU$-factorization. It is our hope that this work provides readers a blueprint to apply the powerful tools of ACSV to prove central limit theorems in their own work, making them more accessible to combinatorialists, probabilists, and those in adjacent fields.