what-when-how
In Depth Tutorials and Information
service effectiveness and recommendation accuracy, also plays an important role
in these two models. Besides, when the coefficient
α
decreases, malicious nodes
can be detected and punished quickly and the amount of successful transactions
increases stably.
11.4.4 Information Theoretic Trust
he information theoretic trust scheme [30,31] can be used to compute the trust
values. Every interaction node
i
updates the direct trust value of node
j
in the case
that node
i
is connected with node
j
directly as below:
−
≤
≤
⎨
1
h p
(
)
0 5
.
p
1
b
Trust
=
i j
,
h p
(
)
−
1 0
≤
p
≤
0 5
.
⎩
b
+
=
s
N
1
2
=
+
=
=
=
p
pr v n
( (
1
)
1
|
n N
(
)
s
)
= −
∑
h p
(
)
p x
( ) log ( )
p x
p
x
⎩
1
node i
,
j interact successfully in th
e m transaction
th
=
V m
(
)
0
otherwise
∑
1
N
n N
(
)
=
V m
(
)
m
Node
i
computes the indirect trust value of the node
j
if node
j
is not included in
the neighborhood of node
i
as follows:
∑
Trust
=
w Trust Trust
i j
,
k
i k
,
k j
,
k N
∈
Trust
Trust
i k
,
w
=
∑
k
i k
,
k N
∈
where
N
is the set of the neighbors of node
i
with
Trust
i,k
>
0. A threshold trust
value
Trust H
=
is set statically.
(
'
)
H
i j
,