  A technique for reducing a tagset used for n-gram part-of-speech
disambiguation is introduced and evaluated in an experiment. The technique
ensures that all information that is provided by the original tagset can be
restored from the reduced one. This is crucial, since we are interested in the
linguistically motivated tags for part-of-speech disambiguation. The reduced
tagset needs fewer parameters for its statistical model and allows more
accurate parameter estimation. Additionally, there is a slight but not
significant improvement of tagging accuracy.
