Exemplarily, looking at both ends of the continuum, see Table 3, within the unknown words present as Wikipedia titles (UW) of the unknown nouns therefrom (N), the Stanford Tagger mistagged only few nouns (SMT).
uW contained some non-nouns (NN), the majority of which led to redirects, disambiguation pages or deleted pages leaving some errors through the method (WE) but excluding relatively many assignments.