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−
η
which holds true with probability at least 1
simultaneously
for all
functions in the
set, since it holds for the worst. Hence, in particular it holds true for the function
ω
I
.
And one gets the bound (13).
For the theorems to follow, we denote the right-hand-side in the Vapnik bound by
V
=
R
emp
(
I
)+
(
ln
N
ω
−
ln
η
)
/
(
2
I
)
.
Theorem 1.
Let
}
ω
j
∈
Ω
,j
=
1
,
2
,...,
N, be a finite set of indicator functions
(classification task) of size N. Then, for any
{
Q
(
z
,
ω
j
)
η
>
0
, arbitrarily small, there is a small
number
n
k
(
n
k
=
1
1
)
k
(
2
)
k
,
α
(
η
,
n
)=
η
−
−
η
(14)
and the number
,
I
,
N
,
n
)=
2
n
n
1
+
1
ln
N
−
ln
η
ε
(
η
−
2
I
+
√
n
+
n
n
−
ln
η
,
(15)
−
1
2
I
such that:
P
|
V
−
C
|≤
ε
(
η
,
I
,
N
,
n
)
≥
1
−
α
(
η
,
n
)
.
(16)
Before we prove theorem 1, the following two remarks should be clear.
Remark 1.
The value of
α
(
η
,
n
)
is monotonous with
η
. I.e. the smaller
η
we choose,
the smaller
α
(
η
,
n
)
becomes as well. Therefore the minimum probability measure 1
−
(
,
n
)
is suitably large.
α
η
η
−
)
k
n
k
(
n
k
=
1
1
)
k
(
2
−
lim
η
→
η
0
+
η
)
k
n
k
(
n
k
=
0
1
)
k
(
2
=
lim
η
→
+
1
−
−
η
0
+
⎛
⎞
⎝
η
)
n
→
1
⎠
=
0
.
=
lim
η
→
0
+
+
1
−
(
1
−
2
η
Remark 2.
For the fixed values of
η
,
N
,
n
,thevalueof
ε
(
η
,
I
,
N
,
n
)
converges to zero as
thesamplesize
I
grows large.