org.apache.spark.mllib.tree.loss
Class SquaredError

Object
  extended by org.apache.spark.mllib.tree.loss.SquaredError
All Implemented Interfaces:
java.io.Serializable, Loss

public class SquaredError
extends Object
implements Loss

:: DeveloperApi :: Class for squared error loss calculation.

The squared (L2) error is defined as: (y - F(x))**2 where y is the label and F(x) is the model prediction for features x.

See Also:
Serialized Form

Constructor Summary
SquaredError()
           
 
Method Summary
static double gradient(double prediction, double label)
          Method to calculate the gradients for the gradient boosting calculation for least squares error calculation.
 
Methods inherited from class Object
equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 
Methods inherited from interface org.apache.spark.mllib.tree.loss.Loss
computeError, computeError, gradient
 

Constructor Detail

SquaredError

public SquaredError()
Method Detail

gradient

public static double gradient(double prediction,
                              double label)
Method to calculate the gradients for the gradient boosting calculation for least squares error calculation. The gradient with respect to F(x) is: - 2 (y - F(x))

Parameters:
prediction - Predicted label.
label - True label.
Returns:
Loss gradient