Information Technology Reference
In-Depth Information
Table 8.1
Overview of the myExperiment Work
ow Dataset
Metrics
Value
Taverna workflows with at least one Web service
347
Unique services
241
Operations
283
Average services per workflow
2.05
Average workflows per service
2.96
Average collaborators per service
4.40
The largest component of service-service network
47%
workflows, that is,
m
¼
347, and
n
is the number of services, that is,
n
¼
241:
Q
¼½
q
ij
,0
i
m
,0
j
n
, where
q
ij
¼
1 if workflow
i
contains service
j
.
We derive two more relations,
W
and
S
, from
Q
as follows:
W
Q
T
¼
Q
¼½
w
ij
,0
i
;
j
m
, where
w
ij
¼
the number of services shared by workflows
i
and
j
and
w
ii
¼
the number of services in workflow
i
; and
Q
T
S
¼
Q
¼½
s
ij
,0
i
;
j
n
, where
s
ij
the number of workflows where both services
i
and
j
are
invoked and
s
ii
¼
¼
the number of workflows where service
i
is
invoked.
Relation Q
Q
represents the 347 workflows that contain services. In the visualiza-
tion of
Q
shown in Figure 8.6, diamonds represent workflows, circles
represent services, and an edge between a diamond and a circle
indicates that the workflow calls the service. We have performed the
statistical analysis of
Q
, with the results summarized in Figure 8.7. Most
workflows contain few services (more than 200 out of 347 workflows
invoked only one service); and only a few workflows contain more than
