Andrew Mccallum's Bow library (CMU) is a very robust toolkit. http://www.cs.cmu.edu/~mccallum/bow/ http://www.cs.cmu.edu/~mccallum/bow/ Very high quality. Mult

Andrew Mccallum's Bow library (CMU) is a very robust toolkit. http://www.cs.cmu.edu/~mccallum/bow/ http://www.cs.cmu.edu/~mccallum/bow/ Very high quality. Multiple people have used it for serious research.