title: information retrieval probabilistic model
body: <p>Do you know where I can find source code(any language) to program an information retrieval system based on the probabilistic model?</p>
  
  <p>I tried to search it on the web and found an algorithm named bm25 or bmf25, but I don't know if it is useful.</p>
  
  <p>Basically I´m trying to compare the performance of 3 IR algorithms: Vector space model, boolean model and the probabilistic model. Right now I have found the vector space and the boolean models. Depending on the results we need to use the best of them to develop a question-answering system</p>
  
  <p>Thanks in advance</p>