1. 6/17/20151 Table Structure Understanding by Sibling Page Comparison Cui Tao Data Extraction Group Department of Computer Science Brigham Young University Supported by NSF

2. 6/17/20152 Table Structure Understanding Motivation Many documents contain tables Data extraction Data integration Ontology evolution Solution Locate tables Locate table labels Locate table values Find label/value associations

3. 6/17/20153 Table Structure Understanding

4. 6/17/20154 Table Structure Understanding 1 2 (Gene Model, 1) = F 1 8H 3.5a (Gene Model, 2) = F 1 8H 3.5b :

5. 6/17/20155

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7. 7 Sibling Pages Generated output pages user query results in predefined page structure Same web site ~ same structure

8. 6/17/20158 Problems Data rich area --- discard the irrelevant parts Find table correspondences Find mappings between table cells Find structure patterns

9. 6/17/20159 HTML Table Components

10. 6/17/201510 Data Rich Area

11. 6/17/201511 Table Unnesting

12. 6/17/201512 DOM Tree

13. 6/17/201513 Simple Tree Matching Simple Tree Matching (STM) Yang91 Maximum matching pairs of nodes O(mn) label Value

14. 6/17/201514 Table Structure Pattern

15. 6/17/201515 Table Structure Pattern

16. 6/17/201516 Experimental Results Initial Test General pattern extraction Molecular biology: 95.6% Car ad: 100% Dynamic adjustment Unseen structure Structure variations