prea.recommender.baseline
Class Random

java.lang.Object
  extended by prea.recommender.baseline.BaselineRecommender
      extended by prea.recommender.baseline.Random
All Implemented Interfaces:
Recommender

public class Random
extends BaselineRecommender

The class implementing a baseline, predicting uniformly randomly from the score range.

Since:
2012. 4. 20
Version:
1.1
Author:
Joonseok Lee

Field Summary
 
Fields inherited from class prea.recommender.baseline.BaselineRecommender
itemCount, maxValue, minValue, rateMatrix, userCount
 
Constructor Summary
Random(int uc, int ic, double max, double min)
          Construct a constant model with the given data.
 
Method Summary
 double predict(int userId, int itemId)
          Predict a rating for the given user and item.
 
Methods inherited from class prea.recommender.baseline.BaselineRecommender
buildModel, evaluate
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

Random

public Random(int uc,
              int ic,
              double max,
              double min)
Construct a constant model with the given data.

Parameters:
uc - The number of users in the dataset.
ic - The number of items in the dataset.
max - The maximum rating value in the dataset.
min - The minimum rating value in the dataset.
Method Detail

predict

public double predict(int userId,
                      int itemId)
Predict a rating for the given user and item.

Specified by:
predict in class BaselineRecommender
Parameters:
userId - The target user.
itemId - The target item.
Returns:
predicted rating.