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Pro<strong>of</strong> <strong>of</strong> Lemma 7.1. We show that<br />
ESk` = ek + `m c1t(k )+o((m=n) )+O(m ;1 ml(log m) k;1 )<br />
+O(m ;1 l log k m)1fk 2g k =0 1::: (7.6)<br />
which implies (7.3). (7.4) follows from (7.6) and Assumption l. To prove (7.6) note that (4.4) and<br />
assumption (a) or Lemma 2.2 or Lemma 2.1 imply<br />
E[ 0<br />
j I( j)] = 1 + (c1=c0) j + rj(1) (7.7)<br />
E[ 0<br />
3j I( 3j)] = 1 + (c1=c0) 3j + rj(3) (7.8)<br />
where rj(1) = o((j=n) )+O(j ;2 ) (without tapering), and rj(3) = o((j=n) )+O(j ;1 log j) (with<br />
tapering). Setting<br />
we can write<br />
Note that<br />
and<br />
tm(k )=m ;1<br />
mX<br />
j=l<br />
k<br />
j (j=m) Rm(k ` )=m ;1<br />
mX<br />
j=l<br />
k<br />
j rj(`) (7.9)<br />
ESk` = tm(k 0) + (c1=c0) `m tm(k )+Rm(k ` ): (7.10)<br />
tm(k )=t(k )+O(l log k m=m) k 0 0 (7.11)<br />
Rm(k ` )=o((m=n) )+O(m ;1 ml(log m) k;1 ) k 0: (7.12)<br />
(7.10)-(7.12) and tm(1 0) = 0 imply (7.6).<br />
To prove (7.11) note that Pm j=1 log j = m log m ; m + O(log m) implies<br />
and therefore<br />
tm(k ) = m ;1<br />
j =log(j=m)+1+O(l log m=m) (7.13)<br />
mX<br />
j=l<br />
(log(j=m)+1) k (j=m) + O(l log k m=m)<br />
= t(k )+o(m ;1=2 ) k 0 0<br />
under Assumption l. To show (7.12) note that (7.13) and (7.11) imply<br />
Therefore<br />
j jj C log m<br />
mX<br />
j=l<br />
j k j j m1=2 (<br />
jRm(k ` )j o((m=n) )m ;1<br />
mX<br />
j=l<br />
mX<br />
j=l<br />
2k<br />
j ) 1=2 Cm k 1: (7.14)<br />
j k j j + Cm;1 log k m<br />
mX<br />
j=l<br />
jrj(`)j<br />
= o((m=n) )+O(m ;1 ml(log m) k;1 ) k 1: