Title
Formulas for Counting the Sizes of Markov Equivalence Classes of Directed Acyclic Graphs.
Abstract
The sizes of Markov equivalence classes of directed acyclic graphs play important roles in measuring the uncertainty and complexity in causal learning. A Markov equivalence class can be represented by an essential graph and its undirected subgraphs determine the size of the class. In this paper, we develop a method to derive the formulas for counting the sizes of Markov equivalence classes. We first introduce a new concept of core graph. The size of a Markov equivalence class of interest is a polynomial of the number of vertices given its core graph. Then, we discuss the recursive and explicit formula of the polynomial, and provide an algorithm to derive the size formula via symbolic computation for any given core graph. The proposed size formula derivation sheds light on the relationships between the size of a Markov equivalence class and its representation graph, and makes size counting efficient, even when the essential graphs contain non-sparse undirected subgraphs.
Year
Venue
Field
2016
arXiv: Machine Learning
Discrete mathematics,Comparability graph,Combinatorics,Tree (graph theory),Line graph,Graph isomorphism,Null graph,Strongly connected component,Mathematics,Moral graph,Graph (abstract data type)
DocType
Volume
Citations 
Journal
abs/1610.07921
2
PageRank 
References 
Authors
0.38
4
2
Name
Order
Citations
PageRank
Yangbo He163.88
Bin Yu21984241.03