prea.util
Class Loss
java.lang.Object
prea.util.Loss
public class Loss
- extends java.lang.Object
This is a class implementing loss functions generally
used in collaborative filtering algorithms.
- Since:
- 2012. 4. 20
- Version:
- 1.1
- Author:
- Joonseok Lee, Mingxuan Sun
Constructor Summary |
Loss()
|
Method Summary |
static double |
asymmetricLoss(double realRate,
double predictedRate,
double minValue,
double maxValue)
Asymmetric loss matrix/function. |
private static int |
bound(double value,
double minValue,
double maxValue)
Return the rounded index for a rating in a given range |
Methods inherited from class java.lang.Object |
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait |
Loss
public Loss()
asymmetricLoss
public static double asymmetricLoss(double realRate,
double predictedRate,
double minValue,
double maxValue)
- Asymmetric loss matrix/function.
Note that this should be used only for discrete ratings.
- Parameters:
realRate
- Target real rating.predictedRate
- Target predicted rating.minValue
- Possible minimum value of the domain.maxValue
- Possible maximum value of the domain.
- Returns:
- Asymmetric loss for the given target rating.
bound
private static int bound(double value,
double minValue,
double maxValue)
- Return the rounded index for a rating in a given range
- Parameters:
value
- The target rating to bound.minValue
- The minimum of given range.maxValue
- The maximum of given range.
- Returns:
- the bounded index.