[mlpack-svn] [MLPACK] #337: Normalization for Collaborative Filtering

[MLPACK Trac]

#337: Normalization for Collaborative Filtering
---------------------------+------------------------------------------------
 Reporter:  sumedhghaisas  |        Owner:                                        
     Type:  defect         |       Status:  new                                   
 Priority:  major          |    Milestone:  mlpack 1.0.9                          
Component:  mlpack         |     Keywords:  Normalization, Collaborative Filtering
 Blocking:                 |   Blocked By:                                        
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 Option added for collaborative filtering model to perform normalization
 before applying ALS. The normalizations replaces all the missing entries
 with column averages and then subtracts row averages from all the entries.
 Laplace's Smoothing is added for smoothening the sparse rating matrix.

 Files Included:
 1) cf.cpp : Added default constructor parameter normalize. CleanData is
 modified to
             apply laplace's smoothing and compute comulmnAverages and
 rowAverages.
             Sparse matrix is not modified at this stage. The normalization
 will be
             while actually performing ALS (through NMF).
 2) als_normalized_update_rule : WNormalizedAlternatingLeastSqureRule and
                                  HNormalizedAlternatingLeastSquareRule
 2) nmf.hpp : Added template specialized class to handle the added update
 rules
 3) nmf_impl.hpp : Implementation of new Apply method which takes column
 average and  row average matrices

-- 
Ticket URL: <http://trac.research.cc.gatech.edu/fastlab/ticket/337>
MLPACK <www.fast-lab.org>
MLPACK is an intuitive, fast, and scalable C++ machine learning library developed at Georgia Tech.