org.mymedialite.ratingprediction
Class ItemKNNCosine

java.lang.Object
  extended by org.mymedialite.ratingprediction.RatingPredictor
      extended by org.mymedialite.ratingprediction.IncrementalRatingPredictor
          extended by org.mymedialite.ratingprediction.KNN
              extended by org.mymedialite.ratingprediction.ItemKNN
                  extended by org.mymedialite.ratingprediction.ItemKNNCosine
All Implemented Interfaces:
java.lang.Cloneable, IItemSimilarityProvider, IRecommender, IIncrementalRatingPredictor, IRatingPredictor

public class ItemKNNCosine
extends ItemKNN

Weighted item-based kNN with cosine similarity. This recommender supports incremental updates.


Field Summary
 
Fields inherited from class org.mymedialite.ratingprediction.ItemKNN
data_item, memoizer
 
Fields inherited from class org.mymedialite.ratingprediction.KNN
baseline_predictor, correlation, k
 
Fields inherited from class org.mymedialite.ratingprediction.IncrementalRatingPredictor
updateItems, updateUsers
 
Fields inherited from class org.mymedialite.ratingprediction.RatingPredictor
maxItemID, maxRating, maxUserID, minRating, ratings
 
Constructor Summary
ItemKNNCosine()
           
 
Method Summary
 void loadModel(java.lang.String filename)
          Get the model parameters from a file
protected  void retrainItem(int item_id)
          Retrain model for a given item.
 java.lang.String toString()
          Return a string representation of the recommender
 void train()
          Learn the model parameters of the recommender from the training data
 
Methods inherited from class org.mymedialite.ratingprediction.ItemKNN
addItem, addRating, getItemSimilarity, getMostSimilarItems, predict, removeRating, setRatings, updateRating
 
Methods inherited from class org.mymedialite.ratingprediction.KNN
getRegI, getRegU, saveModel, setRegI, setRegU
 
Methods inherited from class org.mymedialite.ratingprediction.IncrementalRatingPredictor
addUser, getUpdateItems, getUpdateUsers, removeItem, removeUser, setUpdateItems, setUpdateUsers
 
Methods inherited from class org.mymedialite.ratingprediction.RatingPredictor
canPredict, clone, getMaxRating, getMinRating, getRatings, setMaxRating, setMinRating
 
Methods inherited from class java.lang.Object
equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait
 
Methods inherited from interface org.mymedialite.ratingprediction.IRatingPredictor
getMaxRating, getMinRating, setMaxRating, setMinRating
 
Methods inherited from interface org.mymedialite.IRecommender
canPredict
 

Constructor Detail

ItemKNNCosine

public ItemKNNCosine()
Method Detail

train

public void train()
Description copied from interface: IRecommender
Learn the model parameters of the recommender from the training data

Specified by:
train in interface IRecommender
Specified by:
train in class RatingPredictor

retrainItem

protected void retrainItem(int item_id)
Description copied from class: ItemKNN
Retrain model for a given item.

Specified by:
retrainItem in class ItemKNN
Parameters:
item_id - the item ID

loadModel

public void loadModel(java.lang.String filename)
               throws java.io.IOException
Description copied from interface: IRecommender
Get the model parameters from a file

Specified by:
loadModel in interface IRecommender
Overrides:
loadModel in class KNN
Parameters:
filename - the file to read from
Throws:
java.io.IOException

toString

public java.lang.String toString()
Description copied from interface: IRecommender
Return a string representation of the recommender

Specified by:
toString in interface IRecommender
Overrides:
toString in class RatingPredictor
Returns:
the class name and all hyperparameters, separated by space characters.