Tree-SVM: Tool for SVM optimization on tree data structures

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OVERVIEW:

Tree-SVM implements SMO decomposition algorithm from Fan et al JMLR 2005.

Tree-SVM supports only binary classification by now. 
Input trees must be encoded in the bracket notation, e.g., "(A (B (C) (D)) (E (F)))" represents the following tree:

     A
    / \
   B   E
  / \   \
 C   D   F 

where "A", "B", "C", "D", "E", "F" are corresponding node labels.

Example of input file:
+1 (beats (clarity (on (#CAMERA))) (out) (easily) (clarity (on (#CAMERA))))
-1 (#CAMERA (is (2.5 (same (as (that (on (#CAMERA))))) (wide))))

Available kernels:
- Intersection kernel (counts the number of common labels for both input trees)
- Subtree kernel (Vishwanathan and Smola, 2001)
- Subset tree kernel (Collins and Duffy, 2002)
- Partial tree kernel (Moschitti, 2006)
- Skip-node kernel (Tkachenko and Lauw, 2015)
- Linear Skip-node kernel (Tkachenko and Lauw, 2015)
- Lookahead Skip-node kernel (Tkachenko and Lauw, 2015)

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HOW TO CITE:

If you use Tree-SVM in your research, please cite the following paper:

Maksim Tkachenko and Hady W. Lauw. A Convolution Kernel Approach to Identifying Comparisons in Text, ACL 2015.

The bibtex format is

@inproceedings{tkachenko-lauw:2015,
  author    = {Maksim Tkachenko and Hady W. Lauw},
  title     = {A Convolution Kernel Approach to Identifying Comparisons in Text},
  booktitle = {Proceedings of the 53rd Annual Meeting of the Association for Computational Linguistics},
  year      = {2015},
  publisher = {Association for Computational Linguistics},
}

If you use Subtree kernel, Subset tree kernel, or Partial tree kernel, please cite the corresponding papers.

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BIBLIOGRAPHY:

@article{fan:2005,
 author = {Fan, Rong-En and Chen, Pai-Hsuen and Lin, Chih-Jen},
 title = {Working Set Selection Using Second Order Information for Training Support Vector Machines},
 journal = {J. Mach. Learn. Res.},
 issue_date = {12/1/2005},
 volume = {6},
 month = dec,
 year = {2005},
 issn = {1532-4435},
 pages = {1889--1918},
 numpages = {30},
 url = {http://dl.acm.org/citation.cfm?id=1046920.1194907},
 acmid = {1194907},
 publisher = {JMLR.org},
} 

@inproceedings{collins-duffy:2002,
 author = {Michael Collins and Nigel Duffy},
 title = {New Ranking Algorithms for Parsing and Tagging: Kernels over Discrete Structures, and the Voted Perceptron},
 booktitle = {Proceedings of 40th Annual Meeting of the Association for Computational Linguistics},
 month = {July},
 year = {2002},
 address = {Philadelphia, Pennsylvania, USA},
 publisher = {Association for Computational Linguistics},
 pages = {263--270},
 url = {http://www.aclweb.org/anthology/P02-1034},
 doi = {10.3115/1073083.1073128}
}

@incollection{smola-vishwanathan:2003,
 title = {Fast Kernels for String and Tree Matching},
 author = {Alex J. Smola and S.v.n. Vishwanathan},
 booktitle = {Advances in Neural Information Processing Systems 15},
 editor = {S. Becker and S. Thrun and K. Obermayer},
 pages = {585--592},
 year = {2003},
 publisher = {MIT Press},
 url = {http://papers.nips.cc/paper/2272-fast-kernels-for-string-and-tree-matching.pdf}
}

@incollection{moschitti:2006,
 year={2006},
 isbn={978-3-540-45375-8},
 booktitle={Machine Learning: ECML 2006},
 volume={4212},
 series={Lecture Notes in Computer Science},
 editor={Fürnkranz, Johannes and Scheffer, Tobias and Spiliopoulou, Myra},
 doi={10.1007/11871842_32},
 title={Efficient Convolution Kernels for Dependency and Constituent Syntactic Trees},
 url={http://dx.doi.org/10.1007/11871842_32},
 publisher={Springer Berlin Heidelberg},
 author={Moschitti, Alessandro},
 pages={318-329},
 language={English}
}