While the index search often provides a reliable candidate, implicit features such as coherence, conceptmention probability and topic similarity are only partially graspable by Wiki and may induce a SVM re-ranking.
the nil prediction c 0 for Taiwan is not counted as a false positive, since we already observe History of China as a false positive, with two true positives from People's Rep. of China and Jiangsu resulting in P = 0.66.