(a) "The data warehouse is a structured repository of integrated, subject-oriented, enterprise-wide, historical, and time-variant data.

(a) "The data warehouse is a structured repository of integrated, subject-oriented, enterprise-wide, historical, and time-variant data. " - Explain the term integrated in the following data warehouse definition. [2 marks] 

(b) Elaborate, using examples, on how Data Mining is used in the following sectors: 

(i) Brokerage and Securities Trading 

(ii) Insurance 

[2 x 2 marks] 

(c) A mobile company wants to evaluate its customers' usage of Value Added Services (VAS) to devise a new marketing campaign. Your have been requested to propose an OLAP cube to keep track of the number of customers using the different VAS over time. Examples of VAS are SMS, MMS, RingBackTone, MissCallAlerts.  

(i) Explain the term OLAP. 

[2 marks] 

(ii) Identify three dimensions and their hierarchies to be used in the OLAP cube. 

[3 marks] 

(iii) Illustrate your OLAP cube using a diagram. You should also show a dice and a slice of the cube. [2 + 1+ 1 marks] 

(d) List FIVE aspects that need to be considered when evaluating the quality of data [5 *1 marks]