单一样本
i
i
i的轮廓系数：
s
(
i
)
=
b
(
i
)
?
a
(
i
)
max
?
{
a
(
i
)
,
b
(
i
)
}
s(i)=\frac{b(i)-a(i)}{\max\{a(i),b(i)\}}
s(i)=max{a(i),b(i)}b(i)?a(i)?
其中
a
(
i
)
a(i)
a(i):
i
i
i所属簇内其它样本的平均距离，若簇内仅
i
i
i一个样本，则令
s
(
i
)
=
0
s(i)=0
s(i)=0
i
∈
A
,
a
(
i
)
=
a
v
e
r
a
g
e
j
∈
A
,
j
≠
i
(
d
i
s
t
(
i
,
j
)
)
i \in A,a(i)=average_{j \in A,j \neq i}(dist(i,j))
i∈A,a(i)=averagej∈A,j?=i?(dist(i,j))
b
(
i
)
b(i)
b(i):
i
i
i与其它簇的样本平均距离的最小值
i
∈
A
,
C
≠
A
,
d
i
s
t
(
i
,
C
)
=
a
v
e
r
a
g
e
j
∈
C
(
d
i
s
t
(
i
,
j
)
)
i \in A,C \neq A,dist(i,C)=average_{j \in C}(dist(i,j))
i∈A,C?=A,dist(i,C)=averagej∈C?(dist(i,j))
b
(
i
)
=
m
i
n
C
≠
A
d
i
s
t
(
i
,
C
)
b(i)=min_{C \neq A} dist(i,C)
b(i)=minC?=A?dist(i,C)