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Hw was due yesterday solutions posted todayHonorow
self grade due ii 3
25 handed un HN all should be able Gunll
Plan todaythen tutti EZ more generally as martingale
Aaaaa Heffding as generalization of Halfdryfor sum of non uhdependent variables
Proof of McDiarmid via Asama Hoeffding
HoeffdayguCZ In 2 Zi EZ where 2 i were E abgaussian RV
independent
z n EEDi
galt O IF Di O
Sg II DiSgt 7 Sg s Dg gigadding
randomness to Sj
S E gutt 0 S i add D
Gutt Sn E Di adding rammodomness sequentiallyi 4
Here all D are wedependent
Sj E gue l Zi ZjElsie I Zi 2jJ ELECgnEEIIZi.ituJ1Zi ZjJ ElgnEH4Z
if El Sj Is in for all j Sj is aSJ
martingale sequenceWrt Ziti adapted to filtration
Dj Sj Sj is a martingale
generated by Ziti
difference sequence
guta.EE Ez EDi PIC
guyEigula the
just by G is so subgaussian candirectly bound
by Hoeffday's inequality P yDie
Nof assume get is an arbitrary function ofindependent 2 i
eamare war 6 h eEt EEEIbe lcaiifl
tUgz Sn So E Sj Sj uFnateF n je
2 Djje
Dj Elgula l Z 2JI E Ign 17 Zji
additional randomness by conditioning on 2J
If Eelguellen Sjfa is a doob
Sig El Cgu It zj3martingale sequence
Edgell za aj J Sj EIS ka
in order to show concentration on Ig i
need some conditions on Di
Ele Ifp j e ei
FIEFfor almost allof Cemil Zizi 4244 9 1 eZ Zin
Di l ti Z 1almost surely bounded
the event where Di IZ 44 E Cai bird
for some aEbi has probability d
Azunaltoeffdingareguality
If martingale difference sequence i Fi Din
satisfies Di IZ Zia E Cai bid for almost
all ti Zit then
CEN Dist ee i aifProof
T.ff.ar.ir is c Cai bi then it s big subganssian
For Ele iz z eeMb4I
at ri
e
a
Eaa big
i
Not If ga Z IR satisfiesh
bounded difference condition then
o.si 9giEssiEe
If
McDianidine quattyFor any ma
c Z defu Ehby27g zj if jelle and oink 2 u
If gu E712 satisfies for any zit
cZ
and all he 4 n we have
1gCal GE'T I E oucbdiffmd.de
u n condition
then Ip Capiz Earth He
Eep
e EEif Z Za are
independent RV
Proof by showingt Azuma Heeffetug
Define the Ezio 2 a
E Cguthlzi I It Rguczi IT because of independerof 7 Zn
i iz'T zi'll IE Lgu Iai Zi Elgin l z't IIM LEE gulti ZiZiel Ezingulai Zazie
mGSEP E g Ei Ziel inzf
Ezii.guizihitiimete.tk'sdoesn'tget f E IgaCt't izZiti gnat a'it pthe tight McDiarmidboundCapitol Earth ee EEFiiq.lguczi gu.tt l Oi
U aw E eczift
Define Gutt µf pRCH Ralf and l is uniformly
atbonded by E
262P Cga
CH Eg.CZt ee
C.FI ftRf2RRtt7eeE go.cz E 272 be
µ E aEZi eczi.fihoax2e 5h leche la f t feel