2. Advance Information Retrieval Topics Hassan Bashiri

3. Information Filtering

4. Agenda Information filtering Automatic profile learning Social filtering Training Strategies

5. Information Access Problems Collection Information Need Stable Different Each Time Data Mining Retrieval Filtering Different Each Time

6. Indexing and Complexity

7. Agenda Inverted indexes Computational complexity

8. An Example quick brown fox over lazy dog back now time all good men come jump aid their party 0 0 1 1 0 0 0 0 0 1 0 0 1 0 1 1 0 0 1 0 0 1 0 0 1 0 0 1 1 0 0 0 0 1 Term Doc 1Doc 2 0 0 1 1 0 1 1 0 1 1 0 0 1 0 1 0 0 1 1 0 0 1 0 0 1 0 0 1 0 0 0 0 0 1 Doc 3 Doc 4 0 0 0 1 0 1 1 0 0 1 0 0 1 0 0 1 0 0 1 0 0 1 0 0 1 0 0 0 1 0 1 0 0 1 Doc 5Doc 6 0 0 1 1 0 0 1 0 0 1 0 0 1 0 0 1 0 1 0 0 0 1 0 0 1 0 0 1 1 1 1 0 0 0 Doc 7Doc 8 A B C F D G J L M N O P Q T AI AL BA BR TH TI 4, 8 2, 4, 6 1, 3, 7 1, 3, 5, 7 2, 4, 6, 8 3, 5 3, 5, 7 2, 4, 6, 8 3 1, 3, 5, 7 2, 4, 8 2, 6, 8 1, 3, 5, 7, 8 6, 8 1, 3 1, 5, 7 2, 4, 6 Postings Inverted File

9. The Finished Product quick brown fox over lazy dog back now time all good men come jump aid their party Term A B C F D G J L M N O P Q T AI AL BA BR TH TI 4, 8 2, 4, 6 1, 3, 7 1, 3, 5, 7 2, 4, 6, 8 3, 5 3, 5, 7 2, 4, 6, 8 3 1, 3, 5, 7 2, 4, 8 2, 6, 8 1, 3, 5, 7, 8 6, 8 1, 3 1, 5, 7 2, 4, 6 PostingsInverted File

10. Cross-Language Information Retrieval

11. Agenda Cross-language IR –Controlled vocabulary Automatic indexing –Free text –Evaluation –User interface design

12. 11 What is CLIR? Users enter their query in one language and the search engine retrieves relevant documents in other languages. Retrieval System English QueryFrench Documents

13. 11 Term-aligned Sentence-aligned Document-aligned Unaligned Parallel Comparable Knowledge-based Corpus-based Controlled Vocabulary Free Text Cross-Language Text Retrieval Query Translation Document Translation Text Translation Vector Translation Ontology-based Dictionary-based Thesaurus-based

14. Agenda Retrieval of still images Audio indexing

15. Retrieval System Interfaces

16. Agenda Query interface Selection interface Examination interface Document delivery

17. Retrieval System Model Query Formulation Detection Delivery Selection Examination Index Docs User Indexing

18. Query Formulation Query Formulation Detection User Index

19. Starfield

20. Search Engine Organization

21. NLP in IR

22. The Different Levels of Language Analysis 1-Phonetic or Phonological Level 2-Morphological Level 3-Syntactic Level 4-Semantic Level 5-Discourse Level

23. How Information Retrieval Works Step 1: Document Processing Step 2: Query Processing Step 3: Query Matching Step 4: Ranking & Sorting

24. Intelligent Information Retrieval or Knowledge Based IR

25. What Is Different From IR? IR is more concerned with words and concepts. IIR or KBIR is more concerned about relations. Most of IR models assume term independence. IIR or KBIR acknowledges existence of relationships. IR more suitable for large scale and general retrieval IIR or KBIR more suitable for domain specific tasks.

26. Knowledge Based IR

27. IIR-KBIR Expectation or Interaction With User Objects KB Relation Between the objects Reasoning Learning Relation Extraction

28. Experiments in Farsi Retrieval

29. Retrieval Models Investigated Fuzzy Logic –MMM, Paice Vector Space Probabilistic, BM25 N-Grams Combinational