recommender economy


recommender model



  U = user
  I = item
  B = behavior
  R = recommendation
  F = feature
  

  B = [ time = 20sec, rating = r ]
  F = [ artist = rembrandt, topic = portrait ]
  R = [ artist(rembrandt) = r, topic(portrait) = r ]
  

  A = [  p_{1}, p_2 , ... ]
  where p_{k} = [ f_1 = v_1, f_2 = v_2, ... ]
  
with as an example

   A_{nightwatch} = [ artist=rembrandt, topic=group ]
   A_{guernica} = [ artist=picasso, topic=group ]
  

...


users, artworks and properties

distance metric



       d(x,y) = d(y,x)
       d(x,y) <= d(x,z) + d(z,y)
       d(x,x) = 0
  

dimension(s)


interpretation(s)