Database Reference
In-Depth Information
where LT
(
o
,{
o
},X D ( o , A ) , σ )
is the local simple typicality of o in its representing
region D
(
o
,
A
)
and N
=
D
(
o
,
A
)
D
( {
o
}, σ )
is the
σ
-neighborhood region of o in
its representing region D
(
o
,
A
)
.
Definition 4.6 (Local representative typicality). Given an uncertain object O ,a
neighborhood threshold
be the random
vector generating the samples O , the local representative typicality of an object
o
σ
and a reported answer set A
O , let
X
(
)
(
,
,X , σ)=
(
∪{
},X , σ )
(
,X , σ )
O
A
is LRT
o
A
LGT
A
o
LGT
A
.
For any instance o
A , let N
(
o
,
A
,
O
)= {
x
|
x
O
D
(
o
,
A
) }
be the set of in-
stances in O that lie in D
(
o
,
A
)
, then LN
( {
o
},
N
(
o
,
A
,
O
) , σ )
is the
σ
-neighborhood
of o in N
(
o
,
A
,
O
)
. The local group typicality LGT
(
A
,X , σ )
can be estimated using
) , σ ) · | LN ( { o }, N ( o , A , O ) , σ ) |
|
LGT
(
A
,
O
, σ)= o A LT
(
o
,{
o
},
N
(
o
,
A
,
O
. Hence, the lo-
O
|
cal representative typicality is estimated by LRT
(
o
,
A
,
O
, σ)=
LGT
(
A
∪{
o
},
O
, σ )
LGT
.
Local representative typicality can approximate representative typicality with
good quality, as shown below.
(
A
,
O
, σ )
Theorem 4.7 (Local representative typicality approximation). Given an uncer-
tain object O, a neighborhood threshold
σ
, and an answer set A
O, let
o
=
arg max o 1 ( O A ) {
LRT
(
o 1 ,
A
,
O
, σ ) }
be the instance in
(
O
A
)
having the largest
local representative typicality value, and o
=
arg max o 2 ( O A ) {
RT
(
o
,
A
,
O
) }
be the
instance in
(
O
A
)
having the largest representative typicality value. Then,
2
h 2
e σ 2
RT
(
o
,
A
,
O
)
RT
(
o
,
A
,
O
) <
(4.13)
2 h 2
π
(
)
Moreover, for any x
O
A
,
1
h 2
e σ 2
|
RT
(
x
,
A
,
O
)
LRT
(
x
,
A
,
O
, σ ) |<
(4.14)
2 h 2
π
Proof. To prove Theorem 4.7, we need the following lemma.
Lemma 4.1 (Local group typicality score approximation). Given an uncertain
object O, a neighborhood threshold
σ
and a reported answer set A
O.
1
h 2
e σ 2
GT
(
A
,
O
)
LGT
(
A
,
O
, σ ) <
(4.15)
2 h 2
π
Proof. For each instance o
A , let N
(
o
,
A
,
O
)
be the set of instances in O that lie in
(
,
)
D
o
A
, according to Equation 4.1, we have
) × | N ( o , O , A ) |
|
1
T
(
o
,
N
(
o
,
O
,
A
)) ·
Pr
(
N
(
o
,
O
,
A
)) =
h | N ( o , O , A ) | x N ( o , O , A ) G h (
x
,
o
O
|
1
h | O |
=
G h (
x
,
o
)
x
N
(
o
,
O
,
A
)
Let N
=
LN
( {
o
},
N
(
o
,
A
,
O
) , σ )
be the
σ
-neighborhood of o in N
(
o
,
A
,
O
)
, then
 
Search WWH ::




Custom Search