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PureMathematicsnØêÆ,2021,11(12),2023-2030
PublishedOnlineDecember2021inHans.http://www.hanspub.org/journal/pm
https://doi.org/10.12677/pm.2021.1112226
@ÏÊŽ½n3‘ÅiÄ¥A^
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®é܌Ƨên†‰ÆïÄ§®
ÂvFϵ2021c117F¶¹^Fϵ2021c128F¶uÙFϵ2021c1215F
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‘Åiħ@ÏÊŽ½n§r²-éó§‘Å››§‘ÅüN
TheApplicationoftheEarlyStopping
TheoreminRandomWalk
PanZhao
InstituteofFundamentalandInterdisciplinarySciences,BeijingUnionUniversity,Beijing
Received:Nov.7
th
,2021;accepted:Dec.8
th
,2021;published:Dec.15
th
,2021
Abstract
Byusingtheearlystoppingtheorem,DiaconisandFillmadeamistakewhendealing
withtheconvergencetostationarityforarandomwalk.Inthepaper,wenotonly
©ÙÚ^:ë.@ÏÊŽ½n3‘ÅiÄ¥A^[J].nØêÆ,2021,11(12):2023-2030.
DOI:10.12677/pm.2021.1112226
ë
correctthemistake,butalsogivethespeedestimationofconvergencetostationarity
fortherandomwalk,byusingtheMarkovinequationandtheearlystoppingtheorem.
Keywords
RandomWalk,TheEarlyStoppingTheorem,StrongStationaryDuality,
StochasticallyDominate,StochasticallyMonotone
Copyright
c
2021byauthor(s)andHansPublishersInc.
This work is licensed undertheCreative Commons Attribution InternationalLicense (CCBY4.0).
http://creativecommons.org/licenses/by/4.0/
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DOI:10.12677/pm.2021.11122262024nØêÆ
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DOI:10.12677/pm.2021.11122262025nØêÆ
ë
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DOI:10.12677/pm.2021.11122262026nØêÆ
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DOI:10.12677/pm.2021.11122262027nØêÆ
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k=i
ep
(k)
n
e
F
(i)
k
,n>i≥0.
DOI:10.12677/pm.2021.11122262028nØêÆ
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d[[7],½n2]•,
e
P´~ˆ…=
P
∞
n=0
e
F
(0)
n
=∞.N´¦,é?¿n≥0,k
e
F
(0)
n
=
1,
P
∞
n=0
e
F
(0)
n
= ∞.Ïd,
e
P´~ˆ.Ï•
e
PØŒ,š±Ï,~ˆ,d[[7],½n5]•,
E
0
eσ
x
∗
=
x
∗
−1
X
k=0
ev
k
.
Ù¥,ev
k
=
P
k
j=0
e
F
(j)
k
ep
j,j+1
,eσ
x
∗
= inf{n≥1 :
e
X
n
= x
∗
}.
5¿
e
T=eσ
x
∗
,ÏdE
e
T= E eσ
x
∗
.Ï•
e
F
(i)
i
= 1,¤±,
e
F
(i)
i+1
=
1
ep
i+1,i+2
i
X
k=i
ep
(k)
i+1
e
F
(i)
k
=
1
ep
i+1,i+2
ep
i+1,i
e
F
(i)
i
= 1.
Ón,Œ¦:
e
F
(i)
i+2
= 1.Ïd,8BŒ,
e
F
(i)
n
= 1,1 ≤i≤n.
E
0
eσ
x
∗
=
x
∗
−1
X
k=0
ev
k
=
x
∗
−1
X
k=0
k
X
j=0
e
F
(j)
k
ep
j,j+1
=
x
∗
−1
X
k=0
2(k+1) = (x
∗
)
2
+x
∗
.
Ïd,E
0
e
T= E
0
eσ
x
∗
= (x
∗
)
2
+x
∗
.Àx
∗
= db/e−1,1−H(x
∗
) ≤e
−b
.Àn= dc/
2
e,k
kπ
n
−πk≤1−H(x
∗
)+H(x
∗
)P
0
(T
∗
>n)
≤e
−b
+
E
0
e
T
n
≤e
−b
+
(x
∗
)
2
+x
∗
n
=e
−b
+
(d
b

e)
2
−d
b

e
d
c

2
e
≤e
−b
+
b
2
+b
c
.
XJc>1,ÏLÀb=
1
2
lnc,·‚
kπ
n
−πk≤
1
c

√
c+
1
4
(lnc)
2
−
1
2
lnc

.
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ZB10202001.
ë•©z
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AnnalsofProbability,18,1483-1522.https://doi.org/10.1214/aop/1176990628
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[2]Diaconis, P. andMiclo, L. (2009)On Timesto Quasi-Stationarity for Birthand DeathProcess-
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[7]x¬¬,oÜ,Ü{Ÿ,ë.lÑžmü)L§OOK[J].®“‰ŒÆÆ(g ,‰Æ
‡),2015,51(3):227-235.
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