title: How to smooth unigrams
body: <p>I have a unigram language model and  i want to smooth the counts. Is add one smoothing the only way or can i use some other smoothing also. I dont think we can use knesser nay as that is for Ngrams with N>=2. Any other smoothing method you know?</p>
  
  <p>How about witten bell?</p>