论文标题
马尔可夫链重新审视
Markov chains revisited
论文作者
论文摘要
对(a)马尔可夫链理论和(b)链的长期行为的严格且在很大程度上具有独立的描述。尽可能多地治疗是概率而不是分析的(我远离半群理论)。就个人而言,我倾向于发现直觉在于前者,而不是后者。该手稿针对那些对将马尔可夫链用作现实现象模型感兴趣的人。因此,我专注于实践中最常见的链条类型(在离散拓扑结构中(时间均匀,最小和直接连接),并选择一个非常熟悉的起点:(Kendall-)Gillespie算法通常用于模拟这些链条。为了将先决条件和技术复杂性保持在最低限度,我采用了一种“裸露的”方法,将专注于链条(而不是更一般的过程)保持在几乎是病态程度上:我广泛使用链条的“跳跃和保持”结构;几乎没有马丁格理论;最小耦合;没有随机演算;而且,即使手稿中的再生和更新(当然!),但它们仅在链条的背景下进行。我还采取了一些额外的步骤来避免在其他文本中遇到的某些假设,这些假设有时被证明是在实践中绊倒块(例如,状态空间的不可约性,测试功能的界限和停止时间的界限)。有关更多详细信息,请参阅序言。
A rigorous and largely self-contained account of (a) the bread-and-butter concepts and techniques in Markov chain theory and (b) the long-term behaviour of chains. As much as possible, the treatment is probabilistic instead of analytical (I stay away from semigroup theory). Personally, I tend to find that the intuition lies with the former and not the latter. This manuscript is geared towards those interested in the use of Markov chains as models of real-life phenomena. For this reason, I focus on the type of chains most commonly encountered in practice (time-homogeneous, minimal, and right-continuous in the discrete topology) and choose a starting point very familiar to this audience: the (Kendall-) Gillespie Algorithm commonly used to simulate these chains. In order to keep the prerequisite knowledge and technical complications to a minimum, I take a 'bare-bones' approach that keeps the focus on chains (instead of more general processes) to an almost pathological degree: I use the 'jump and hold' structure of chains extensively; almost no martingale theory; minimal coupling; no stochastic calculus; and, even though regeneration and renewal (of course!) feature in the manuscript, they do so exclusively in the context of chains. I have also taken some extra steps to avoid imposing certain assumptions encountered in other texts that sometimes prove to be stumbling blocks in practice (e.g., irreducibility of the state space, boundedness of test functions and of stopping times). For more details, see the preface.