On-Line Analytic Processing (OLAP)
Analyze (summarize, consolidate, view, process) along multiple levels of abstraction and from different angles
- Data in databases are often expressed at primitive levels.
- Knowledge is usually expressed at high levels.
- Data may imply concepts at multiple levels:
Tom Jackson Î CS grad Ì student Ì person.
Mining knowledge just at single abstraction level?
- Too low level? -- Raw data or weak rules.
- Too high level? -- Not novel, common sense?
Mining knowledge at multiple levels:
- Provides different views and different abstractions.
- Progressively focuses on "interesting" spots