The document discusses major issues in data mining including mining methodology, user interaction, performance, and data types. Specifically, it outlines challenges of mining different types of knowledge, interactive mining at multiple levels of abstraction, incorporating background knowledge, visualization of results, handling noisy data, evaluating pattern interestingness, efficiency and scalability of algorithms, parallel and distributed mining, and handling relational and complex data types from heterogeneous databases.

1. Major Issues in Data Mining
V. Saranya
AP/CSE
Sri Vidya College of Engineering & Technology, Virudhunagar

3. • Issues
– Mining Methodology
– User interaction
– Performance
– Data types.

4. Mining Methodology & User
Interaction Issues
1. Mining different kinds of knowledge in
database.
 Different users-different knowledge-different way
(with same database)

5. 2. Interactive Mining of knowledge at multiple
levels of abstraction.
 Focus the search patterns.
 Different angles.

6. 4. Data mining query languages and ad hoc
data mining
 High level data mining query language
 Conditions and constraints.

7. 3. Incorporation of background knowledge.
 Background & Domain knowledge.

8. 5. Presentation and visualization of data mining
results.
 Use visual representations.
 Expressive forms like graph, chart, matrices,
curves, tables, etc…
6. Handling noisy or incomplete data.
 Confuse the process
 Over fit the data (apply any outlier analysis,
data cleaning methods)
7.Pattern evaluation- the interestingness
problem.
 Pattern may be uninteresting to the user.
 Solve by user specified constraints.

9. Performance Issues
• Efficiency and scalability of data mining algorithms.
Running time.
Should be opt for huge amount of data.
• Parallel, Distributed and incremental mining
algorithms.
Huge size of database
Wide distribution of data
High cost
Computational complexity
Data mining methods
Solve by; efficient algorithms.

10. Diversity of data Types Issues
• Handling of relational and complex types of
data.
One system-> to mine all kinds of data
Specific data mining system should be
constructed.
• Mining information from heterogeneous
databases and global information systems.
 Web mining uncover knowledge about web
contents, web structure, web usage and web
dynamics