 <p>Two quick thoughts:</p> <ol> <li><p>You can give some threshold for the confidence value you want. For example, mallet is saying that Page 1 belongs to Class A with 90% confidence, accept it. If it is saying that Page 2 belongs to Class C, with 60% confidence, and that is the best value, may be, reject that suggestion. You can get the scores of classification through the function-getClassificationScores (<a href="http://mallet.cs.umass.edu/api/cc/mallet/classify/MaxEnt.html#getClassificationScores(cc.mallet.types.Instance,%20double[])" rel="nofollow">documentation: </a><a href="http://mallet.cs.umass.edu/api/cc/mallet/classify/MaxEnt.html#getClassificationScores(cc.mallet.types.Instance" rel="nofollow">http://mallet.cs.umass.edu/api/cc/mallet/classify/MaxEnt.html#getClassificationScores(cc.mallet.types.Instance</a>, double[])</p></li> <li><p>You can you scikit-learn in python. I have heard that if it doesn't know which class your page belongs to, it will tell <code>NA</code>. </p></li> </ol>