----------------
Initial release.
2011-08-11 Naoaki Okazaki <okazaki at chokkan org>
* CRFsuite 0.12
- [CORE] Optimized the implementation for faster training; approximately 1.4-1.5 x speed up.
- [CORE] Faster routine for computing exp(x) using SSE2.
- [CORE] Restructured the source code to separate routines for CRF graphical models and training algorithms; this is an initial attempt for implementing CRFs with different feature types (e.g., 2nd-order CRF, 1st-order transition features conditioned on observations) and different training algorithms.
- [CORE] Implemented new training algorithms: Averaged Perceptron, Passive Aggressive, and Adaptive Regularization of Weights (AROW).
- [CORE] Removed automatic generation of BOS/EOS features; one can use these features by inserting attributes to the first/last items (e.g., "__BOS__" at the first item and "__EOS__" at the last item).
- [CORE] Fixed some memory-leak problems.
- [CORE] Reduced memory usage in training.
- [CORE] Fixed a crash problem when the model file does not exist in tagging.
- [FRONTEND:LEARN] Training and test sets are maintained by group numbers; specify the group number for hold-out evaluation with "-e" option.
- [FRONTEND:LEARN] Training algorithm is now specified by "-a" option instead of "-p algorithm=".
- [FRONTEND:LEARN] Renamed some training parameters; for example, an L2 regularization coefficient is specified by "c2" instead of "regularization.sigma" (c2 = 0.5 / sigma * sigma; c1 = 1.0 / sigma).
- [FRONTEND:LEARN] Show the list of parameters, default values, and descriptions with "-H" option.
- [FRONTEND:LEARN] Removed the support of comment lines for simplicity; one may forget to escape '' characters in a data set. CRFsuite now does not handle '' as a special character.
- [FRONTEND:TAGGER] Output probabilities of predicted sequences with "-p" option.
- [FRONTEND:TAGGER] Output marginal probabilities of predicted items with "-i" option.
- [API] Numerous changes in API for the enhancements.
- [API] Renamed the library name "libcrf" to "libcrfsuite".
- [API] Renamed the prefix "crf_" to "crfsuite_" in structure and function names.
- [API] Implemented a high-level and easy-to-use API for C++/SWIG (crfsuite.hpp and crfsuite_api.hpp).
- [API] Implemented the Python SWIG module and sample programs; writing a tagger is very easy with this module.
- [SAMPLE] Rewritten samples.
- [SAMPLE] A sample program (template.py) for using feature templates that are compatible with CRF++.
- [SAMPLE] New samples in example directory: Named Entity Recognition (ner.py) using the CoNLL2003 data set, and part-of-speech tagging (pos.py).
- [OTHER] Updated the MSVC solution file to MSVC 2010.
2010-07-16 Naoaki Okazaki <okazaki at chokkan org>
* CRFsuite 0.11
- Renamed crf.h into crfsuite.h to avoid possible conflects in include directories
- Install crfsuite.h to the include directory (suggested by Ingo Glöckner)
2010-01-29 Naoaki Okazaki <okazaki at chokkan org>
* CRFsuite 0.10
- A patch submitted by Hiroshi Manabe (at Kodensha Co., Ltd.) to fix memory leak problems in the tagger.
- Added a new option -r (--reference) for the tagger to output reference labels in parallel with predicted labels.
2009-09-24 Naoaki Okazaki <okazaki at chokkan org>
* CRFsuite 0.9
- Fixed a build problem with liblbfgs 1.8
2009-03-17 Naoaki Okazaki <okazaki at chokkan org>
* CRFsuite 0.8
- Improved the portability of model files across different machine architectures with different byte order; this fixes a crash problem in tagging on some machine architectures.
2009-03-10 Naoaki Okazaki <okazaki at chokkan org>
* CRFsuite 0.7
- Updated RumAVL library to 4.0.0; this fixes a crash problem occurring in feature generation on some machine architectures.
2009-03-07 Naoaki Okazaki <okazaki at chokkan org>
* CRFsuite 0.6
- A new training algorithm, Stochastic Gradient Descent (SGD).
- Updated the L-BFGS routine to liblbfgs 1.7.
- Reduced memory usage in training.
- Supported escape sequences in training/test data.
- Restructured the source code.
- Added a parameter to configure the number of trials for line search.
2008-11-19 Naoaki Okazaki <okazaki at chokkan org>
* CRFsuite 0.5
- Updated the L-BFGS routine to liblbfgs 1.6.
- New parameters lbfgs.stop, lbfgs.delta, lbfgs.linesearch were added.
- Fixed a bug in which the frontend tools could not parse "item:value" format correctly.
- Fixed a bug in computing the accuracy.
- Fixed a bug when the tagger receives an item with no feature.
2008-03-05 Naoaki Okazaki <okazaki at chokkan org>
* CRFsuite 0.4 (the first public release):
- Website and documentation for CRFsuite.
- Tutorial on the CoNLL 2000 chunking shared task.
- Performance comparison on the CoNLL 2000 chunking shared task.
- Bug fix in L2 regularization.
- A number of small improvements for the public release.
2007-12-12 Naoaki Okazaki <okazaki at chokkan org>
* CRFsuite 0.3 (internal release):
- Implemented scaling method for forward/backward algorithm.
- Removed the code for computing the forward/backward algorithm in logarithm domain.
2007-11-30 Naoaki Okazaki <okazaki at chokkan org>
* CRFsuite 0.2 (internal release):
- Orthant-Wise Limited-memory Quasi-Newton (OW-LQN) method for L1 regularization.
- Configurable L-BFGS parameters (number of limited memories, epsilon).
2007-10-29 Naoaki Okazaki <okazaki at chokkan org>
* CRFsuite 0.1 (internal release):
- Initial release.