The Problem of Peer Node Recognition
- 1. FivaTech ： Schema & Template Discovery Reporter ： Che-Min Liao
- 2. Introduction FivaTech is a page-level data extraction system which deduces the data schema and templates for the input pages generated from a CGI program. Tree Merging Schema Detection
- 5. The FivaTech Approach The proposed approach FivaTech contains two modules ： Tree merging Schema detection
- 6. Peer Node Recognition As each tag/node is actually denoted a tree, we can use 2-tree matching algorithm for computing whether two nodes with the same tag are similar. We adopt Yang’s algorithm A more serious problem is score normalization. A typical way to compute a normalized score is the ratio between the numbers of parts in the mapping over the maximum size of the two trees.
- 7. Tree Merging Score Algorithm
- 8. Example
- 10. Pattern Mining
- 11. Optional Node Merging After the mining step, we are able to detect optional nodes based the ocurence vectors .
- 12. The Example of Pattern Tree
- 13. Identifying the Schema Recognize tuple type Recognize order of the set type and optional data.
- 14. Defining the Template Templates can be obtained by segmenting the pattern tree at reference nodes defined below ：
- 15. The Example of Schema
- 16. The Example of Template T( τ 1 ) = (T 1 , (T 2 , Φ ), 0) T( τ 2 ) = ( Φ , (T 3 , Φ ), 0) T( τ 3 ) = ( Φ , (T 4 , T 5 , T 21 ), (0,0)) T( τ 4 ) = ( Φ , (T 6 , T 7 , Φ ), (0,0)) … T( τ 13 ) = ( Φ , (T 20 , Φ ), 2)