is prohibited.
PerfLocal.(S,Q,D):.Data source performance of source S for data D in query Q
Prii: Data, quality, and aggregations priorities, for data D in query Q
Reli: Degree of fulfillment of data source S for query Q and data element D
The global data source performance is computed as:
PerfGlobal(F,Q) = ??‘ ?? HierGlobal(Qj) * PerfLocal(S,Q ,D)
For all queries Qj involving data element D, and given a set F.of a data source and
a set of queries Q. HierGlobal (Qj): Global priority of query Qj.
Example.6:.For the table in Example 5, the local performance for data
source A and query Q1 is computed as 5 * 1 + 5 * 1 + 5 * 1 + 5 * 1 + 4 *
1 + 3 * 1 + 5 * 1 + 5 * 1 + 5 * 1 = 42. The global performance for source
A is: 135 * 42 + 31 * 144 = 10134.
??? Data.source.selection: Although the final source selection is beyond the scope
of the methodology, a document is generated, with a ranking of data sources
for each data. This document will be used in the final data source selection
process. For our case study, the ranking is 1: data source B (global performance
48,468), 2: data source C (global performance 27,702), and 3: data source A
(global performance 10,134).
Phase.V:.Document.Generation
With the information collected on Phases I to IV, a set of requirements documents
is produced. These documents are reviewed by the referent, data producer, and data
consumer users, in order to reach a final agreement for closing the requirements
elicitation phase.
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