classic_squaredloss Class Reference

Inheritance diagram for classic_squaredloss:

Public Member Functions
std::string	getType ()
float	getLoss (shared_data *, float prediction, float label)
float	getUpdate (float prediction, float label, float update_scale, float)
float	getUnsafeUpdate (float prediction, float label, float update_scale)
float	getRevertingWeight (shared_data *sd, float prediction, float eta_t)
float	getSquareGrad (float prediction, float label)
float	first_derivative (shared_data *, float prediction, float label)
float	second_derivative (shared_data *, float, float)
Public Member Functions inherited from loss_function
virtual	~loss_function ()

Detailed Description

Definition at line 83 of file loss_functions.cc.

Member Function Documentation

first_derivative()

float classic_squaredloss::first_derivative ( shared_data *  , float  prediction, float  label  )

inlinevirtual

Implements loss_function.

Definition at line 112 of file loss_functions.cc.

{ return 2.f * (prediction - label); }

getLoss()

float classic_squaredloss::getLoss ( shared_data *  , float  prediction, float  label  )

inlinevirtual

Implements loss_function.

Definition at line 88 of file loss_functions.cc.

  {
    float example_loss = (prediction - label) * (prediction - label);
    return example_loss;
  }

getRevertingWeight()

float classic_squaredloss::getRevertingWeight ( shared_data *  sd, float  prediction, float  eta_t  )

inlinevirtual

Implements loss_function.

Definition at line 104 of file loss_functions.cc.

References shared_data::max_label, and shared_data::min_label.

  {
    float t = 0.5f * (sd->min_label + sd->max_label);
    float alternative = (prediction > t) ? sd->min_label : sd->max_label;
    return (t - prediction) / ((alternative - prediction) * eta_t);
  }

getSquareGrad()

float classic_squaredloss::getSquareGrad ( float  prediction, float  label  )

inlinevirtual

Implements loss_function.

Definition at line 111 of file loss_functions.cc.

{ return 4.f * (prediction - label) * (prediction - label); }

getType()

std::string classic_squaredloss::getType ( )

inlinevirtual

Implements loss_function.

Definition at line 86 of file loss_functions.cc.

{ return "classic"; }

getUnsafeUpdate()

float classic_squaredloss::getUnsafeUpdate ( float  prediction, float  label, float  update_scale  )

inlinevirtual

Implements loss_function.

Definition at line 99 of file loss_functions.cc.

  {
    return 2.f * (label - prediction) * update_scale;
  }

getUpdate()

float classic_squaredloss::getUpdate ( float  prediction, float  label, float  update_scale, float    )

inlinevirtual

Implements loss_function.

Definition at line 94 of file loss_functions.cc.

  {
    return 2.f * (label - prediction) * update_scale;
  }

second_derivative()

float classic_squaredloss::second_derivative ( shared_data *  , float  , float    )

inlinevirtual

Implements loss_function.

Definition at line 113 of file loss_functions.cc.

{ return 2.; }

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The documentation for this class was generated from the following file:

• /mnt/c/w/linux/vowpal_wabbit/vowpalwabbit/loss_functions.cc