Let {X n ; n â‰¥ 1} be a strictly stationary negatively associated sequence which satisfies EX 1 = 0, V ar(X 1) < âˆž. Set S n = n k=1 X k , n â‰¥ 1, Ïƒ 2 = EX 2 1 + 2 âˆž k=2 EX 1 X k. In this paper, weâ€¦ (More)

A tree T is a graph which is connected and contains no circuits. Given any two vertices Î± Ì¸ = Î² âˆˆ T. Let Î±Î² be the unique path connecting Î± and Î². Define the distance d(Î±, Î²) to be the number ofâ€¦ (More)

* Correspondence: shizhiyan1984@126.com Faculty of Science, Jiangsu University, Zhenjiang, 212013, China Full list of author information is available at the end of the article Abstract In this paper,â€¦ (More)