shark::RegularizationNetworkTrainer< InputType > Class Template Reference

Training of a regularization network. More...

#include <shark/Algorithms/Trainers/RegularizationNetworkTrainer.h>

+ Inheritance diagram for shark::RegularizationNetworkTrainer< InputType >:

Public Types

typedef AbstractModel< InputType, RealVector > ModelType
 
typedef AbstractKernelFunction< InputTypeKernelType
 
- Public Types inherited from shark::AbstractSvmTrainer< InputType, RealVector, KernelExpansion< InputType > >
typedef AbstractKernelFunction< InputTypeKernelType
 
- Public Types inherited from shark::AbstractTrainer< Model, LabelTypeT >
typedef Model ModelType
 
typedef ModelType::InputType InputType
 
typedef LabelTypeT LabelType
 
typedef LabeledData< InputType, LabelTypeDatasetType
 
- Public Types inherited from shark::IParameterizable<>
typedef RealVector ParameterVectorType
 

Public Member Functions

 RegularizationNetworkTrainer (KernelType *kernel, double betaInv, bool unconstrained=false)
 
std::string name () const
 From INameable: return the class name. More...
 
double noiseVariance () const
 Returns the assumed noise variance (i.e., 1/C) More...
 
void setNoiseVariance (double betaInv)
 Sets the assumed noise variance (i.e., 1/C) More...
 
double precision () const
 Returns the precision (i.e., C), the inverse of the assumed noise variance. More...
 
void setPrecision (double beta)
 Sets the precision (i.e., C), the inverse of the assumed noise variance. More...
 
void train (KernelExpansion< InputType > &svm, const LabeledData< InputType, RealVector > &dataset)
 
- Public Member Functions inherited from shark::AbstractSvmTrainer< InputType, RealVector, KernelExpansion< InputType > >
 AbstractSvmTrainer (KernelType *kernel, double C, bool offset, bool unconstrained=false)
 
 AbstractSvmTrainer (KernelType *kernel, double negativeC, double positiveC, bool offset, bool unconstrained=false)
 
double C () const
 Return the value of the regularization parameter C. More...
 
void setC (double C)
 Set the value of the regularization parameter C. More...
 
RealVector const & regularizationParameters () const
 
void setRegularizationParameters (RealVector const &regularizers)
 Set the value of the regularization parameter C. More...
 
KernelTypekernel ()
 
KernelType const * kernel () const
 
void setKernel (KernelType *kernel)
 
bool isUnconstrained () const
 
bool trainOffset () const
 
std::size_t cacheSize () const
 
void setCacheSize (std::size_t size)
 
RealVector parameterVector () const
 get the hyper-parameter vector More...
 
void setParameterVector (RealVector const &newParameters)
 set the vector of hyper-parameters More...
 
size_t numberOfParameters () const
 return the number of hyper-parameters More...
 
- Public Member Functions inherited from shark::AbstractTrainer< Model, LabelTypeT >
virtual void train (ModelType &model, DatasetType const &dataset)=0
 Core of the Trainer interface. More...
 
- Public Member Functions inherited from shark::INameable
virtual ~INameable ()
 
- Public Member Functions inherited from shark::ISerializable
virtual ~ISerializable ()
 Virtual d'tor. More...
 
virtual void read (InArchive &archive)
 Read the component from the supplied archive. More...
 
virtual void write (OutArchive &archive) const
 Write the component to the supplied archive. More...
 
void load (InArchive &archive, unsigned int version)
 Versioned loading of components, calls read(...). More...
 
void save (OutArchive &archive, unsigned int version) const
 Versioned storing of components, calls write(...). More...
 
 BOOST_SERIALIZATION_SPLIT_MEMBER ()
 
- Public Member Functions inherited from shark::QpConfig
 QpConfig (bool precomputedFlag=false, bool sparsifyFlag=true)
 Constructor. More...
 
QpStoppingConditionstoppingCondition ()
 Read/write access to the stopping condition. More...
 
QpStoppingCondition const & stoppingCondition () const
 Read access to the stopping condition. More...
 
QpSolutionPropertiessolutionProperties ()
 Access to the solution properties. More...
 
bool & precomputeKernel ()
 Flag for using a precomputed kernel matrix. More...
 
bool const & precomputeKernel () const
 Flag for using a precomputed kernel matrix. More...
 
bool & sparsify ()
 Flag for sparsifying the model after training. More...
 
bool const & sparsify () const
 Flag for sparsifying the model after training. More...
 
bool & shrinking ()
 Flag for shrinking in the decomposition solver. More...
 
bool const & shrinking () const
 Flag for shrinking in the decomposition solver. More...
 
bool & s2do ()
 Flag for S2DO (instead of SMO) More...
 
bool const & s2do () const
 Flag for S2DO (instead of SMO) More...
 
unsigned int & verbosity ()
 Verbosity level of the solver. More...
 
unsigned int const & verbosity () const
 Verbosity level of the solver. More...
 
unsigned long long const & accessCount () const
 Number of kernel accesses. More...
 
void setMinAccuracy (double a)
 
void setMaxIterations (unsigned long long i)
 
void setTargetValue (double v)
 
void setMaxSeconds (double s)
 
- Public Member Functions inherited from shark::IParameterizable<>
virtual ~IParameterizable ()
 

Additional Inherited Members

- Protected Attributes inherited from shark::AbstractSvmTrainer< InputType, RealVector, KernelExpansion< InputType > >
KernelTypem_kernel
 
RealVector m_regularizers
 Vector of regularization parameters. More...
 
bool m_trainOffset
 
bool m_unconstrained
 Is log(C) stored internally as a parameter instead of C? If yes, then we get rid of the constraint C > 0 on the level of the parameter interface. More...
 
std::size_t m_cacheSize
 Number of values in the kernel cache. The size of the cache in bytes is the size of one entry (4 for float, 8 for double) times this number. More...
 
- Protected Attributes inherited from shark::QpConfig
QpStoppingCondition m_stoppingcondition
 conditions for when to stop the QP solver More...
 
QpSolutionProperties m_solutionproperties
 properties of the approximate solution found by the solver More...
 
bool m_precomputedKernelMatrix
 should the solver use a precomputed kernel matrix? More...
 
bool m_sparsify
 should the trainer sparsify the model after training? More...
 
bool m_shrinking
 should shrinking be used? More...
 
bool m_s2do
 should S2DO be used instead of SMO? More...
 
unsigned int m_verbosity
 verbosity level (currently unused) More...
 
unsigned long long m_accessCount
 kernel access count More...
 

Detailed Description

template<class InputType>
class shark::RegularizationNetworkTrainer< InputType >

Training of a regularization network.

A regularization network is a kernel-based model for regression problems. Given are data tuples \( (x_i, y_i) \) with x-component denoting input and y-component denoting a real-valued label (see the tutorial on label conventions; the implementation uses RealVector), a kernel function k(x, x') and a regularization constant \( C > 0\). Let H denote the kernel induced reproducing kernel Hilbert space of k, and let \( \phi \) denote the corresponding feature map. Then the SVM regression function is of the form

\[ f(x) = \langle w, \phi(x) \rangle + b \]

with coefficients w and b given by the (primal) optimization problem

\[ \min \frac{1}{2} \|w\|^2 + C \sum_i L(y_i, f(x_i)), \]

where the simple quadratic loss is employed:

\[ L(y, f(x)) = (y - f(x))^2 \]

Regularization networks can be interpreted as a special type of support vector machine (for regression, with squared loss, and thus with non-sparse weights).

Training a regularization network is identical to training a Gaussian process for regression. The parameter \( C \) then corresponds precision of the noise (denoted by \( \beta \) in Bishop's textbook). The precision is the inverse of the variance of the noise. The variance of the noise is denoted by \( \sigma_n^2 \) in the textbook by Rasmussen and Williams. Accordingly, \( C = 1/\sigma_n^2 \).

Definition at line 86 of file RegularizationNetworkTrainer.h.

Member Typedef Documentation

◆ KernelType

◆ ModelType

template<class InputType>
typedef AbstractModel<InputType, RealVector> shark::RegularizationNetworkTrainer< InputType >::ModelType

Definition at line 89 of file RegularizationNetworkTrainer.h.

Constructor & Destructor Documentation

◆ RegularizationNetworkTrainer()

template<class InputType>
shark::RegularizationNetworkTrainer< InputType >::RegularizationNetworkTrainer ( KernelType kernel,
double  betaInv,
bool  unconstrained = false 
)
inline
Parameters
kernelKernel
betaInvInverse precision, equal to assumed noise variance, equal to inverse regularization parameter C
unconstrainedIndicates exponential encoding of the regularization parameter

Definition at line 96 of file RegularizationNetworkTrainer.h.

Member Function Documentation

◆ name()

template<class InputType>
std::string shark::RegularizationNetworkTrainer< InputType >::name ( ) const
inlinevirtual

From INameable: return the class name.

Reimplemented from shark::INameable.

Definition at line 101 of file RegularizationNetworkTrainer.h.

◆ noiseVariance()

template<class InputType>
double shark::RegularizationNetworkTrainer< InputType >::noiseVariance ( ) const
inline

◆ precision()

template<class InputType>
double shark::RegularizationNetworkTrainer< InputType >::precision ( ) const
inline

Returns the precision (i.e., C), the inverse of the assumed noise variance.

Definition at line 112 of file RegularizationNetworkTrainer.h.

References shark::AbstractSvmTrainer< InputType, RealVector, KernelExpansion< InputType > >::C().

◆ setNoiseVariance()

template<class InputType>
void shark::RegularizationNetworkTrainer< InputType >::setNoiseVariance ( double  betaInv)
inline

Sets the assumed noise variance (i.e., 1/C)

Definition at line 108 of file RegularizationNetworkTrainer.h.

References shark::AbstractSvmTrainer< InputType, RealVector, KernelExpansion< InputType > >::C().

◆ setPrecision()

template<class InputType>
void shark::RegularizationNetworkTrainer< InputType >::setPrecision ( double  beta)
inline

Sets the precision (i.e., C), the inverse of the assumed noise variance.

Definition at line 115 of file RegularizationNetworkTrainer.h.

References beta, and shark::AbstractSvmTrainer< InputType, RealVector, KernelExpansion< InputType > >::C().

◆ train()


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