当前位置: X-MOL 学术Stat. Probab. Lett. › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Moments of the first descending epoch for a random walk with negative drift
Statistics & Probability Letters ( IF 0.8 ) Pub Date : 2022-06-01 , DOI: 10.1016/j.spl.2022.109547
Sergey Foss , Timofei Prasolov

We consider the first descending ladder epoch τ=min{n1:Sn0} of a random walk Sn=1nξi,n1 with i.d.d. summands having a negative drift Eξ=a<0. Let ξ+=max(0,ξ1). It is well-known that, for any α>1, the finiteness of E(ξ+)α implies the finiteness of Eτα and, for any λ>0, the finiteness of Eexp(λξ+) implies that of Eexp(cτ) where c>0 is, in general, another constant that depends on the distribution of ξ1. We consider the intermediate case, assuming that Eexp(g(ξ+))< for a positive increasing function g such that lim infxg(x)/logx= and lim supxg(x)/x=0, and that Eexp(λξ+)=, for all λ>0. Assuming a few further technical assumptions, we show that then Eexp((1ɛ)g((1δ)aτ))<, for any ɛ,δ(0,1).



中文翻译:

负漂移随机游走的第一个下降纪元的时刻

我们考虑第一个下降阶梯时期τ=分钟{n1小号n0}随机游走小号n=1nξ一世,n1具有负漂移的 idd 和数ξ=-一个<0. 让ξ+=最大限度(0,ξ1). 众所周知,对于任何α>1, 的有限性(ξ+)α意味着有限性τα并且,对于任何λ>0, 的有限性经验(λξ+)意味着经验(Cτ)在哪里C>0是,一般来说,另一个常数,取决于分布ξ1. 我们考虑中间情况,假设经验(G(ξ+))<为正增函数G这样林infXG(X)/日志X=林燮XG(X)/X=0, 然后经验(λξ+)=, 对所有人λ>0. 假设一些进一步的技术假设,我们证明了经验((1-ε)G((1-δ)一个τ))<, 对于任何ε,δ(0,1).

更新日期:2022-06-01
down
wechat
bug