劉玥雯,王才士,普麗琴
(西北師范大學(xué)數(shù)學(xué)與統(tǒng)計學(xué)院,甘肅蘭州730070)
2011年,X.J.Wang等[1]建立了 1 <p≤2 條件下的漸近幾乎負(fù)相協(xié)(AANA)隨機(jī)變量序列的Hájek-Rényi型不等式.Hájek-Rényi(簡稱 HR)型不等式是J.Hájek等[2]在1955年發(fā)現(xiàn)和證明的,定理內(nèi)容是:若{Xn,n≥1}是獨立隨機(jī)變量序列且均值為零,{bn,n≥1}是一非負(fù)不減實數(shù)序列,那么對?ε>0和任意正整數(shù)m≤n有
這個不等式引起了不少學(xué)者的興趣.例如,B.L.S.Rao[3]給出了正相協(xié)(PA)隨機(jī)變量序列的H-R 型不等式,之后,S.H.Sung[4]改進(jìn)了該不等式,并給出了一些應(yīng)用;M.H.Ko等[5]應(yīng)用 H-R型不等式得到AANA序列加權(quán)和的強(qiáng)大數(shù)定律.
定義 1[6]稱{Xn,n≥1}為 AANA 隨機(jī)變量序列,如果存在一個非負(fù)序列q(n)→0,對所有n,k≥1滿足
其中,f和g是使上式有意義,對各變元不降且使(1)式右端有限的函數(shù).
AANA序列是一類非常廣泛的隨機(jī)變量序列,它包含負(fù)相協(xié)(NA)序列和相互獨立隨機(jī)變量序列.由于AANA序列在可靠性理論和多元統(tǒng)計分析中有著廣泛應(yīng)用,所以研究AANA序列的收斂性和極限定理具有重要的實際意義,與其有關(guān)的應(yīng)用也被更多的發(fā)現(xiàn)和推廣.例如,X.J.Wang等[1]得到了AANA序列的大偏差和Marcinkiewicz型強(qiáng)大數(shù)定律;T.K.Chandra等[6]獲得了 AANA序列加權(quán)平均的幾乎必然收斂;X.J.Wang等[7]給出了AANA序列部分和的強(qiáng)大數(shù)定律和強(qiáng)收斂速率;D.M.Yuan等[8]建立了 AANA序列部分和的Rosenthal型不等式等.
本文在3·2k-1<p≤4·2k-1的條件下建立了AANA隨機(jī)變量序列的H-R型不等式,并應(yīng)用此不等式得到了AANA隨機(jī)變量序列的部分和收斂定理、強(qiáng)大數(shù)定律和上確界可積性定理.
為了證明本文的主要結(jié)論,需要給出以下引理.
引理 1[8]令{Xn,n≥1}是一列均值為零的AANA隨機(jī)變量序列,其混合系數(shù)為{q(n),n≥1},且p∈(3·2k-1,4·2k-1],整數(shù)k≥1.若<∞,則存在一個只依賴于p的非負(fù)常數(shù)Dp,使得對所有n≥1有
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