Bug Found In EM Code

I found a bug in my rewritten EM Code.

When I was updating u, the denominator was wrong. I shouldnt use num of features in it, as u is dependent on the position of feature. I should use the number of distinctive features on that position instead. so that the summation can be 1.

the retested using topic number = 20 on senseval2 is 62.2% (higher than the wrong 61.9%)

still need to turn on/off pos/word to see the effect.