vita::dss Class Reference

Dynamic training Subset Selection. More...

#include <dss.h>

Inherits vita::validation_strategy.

Public Member Functions
void	close (unsigned) override
	Moves all the example in the validation set. More...
	dss (src_problem &, cached_evaluator &, cached_evaluator &)
	Sets up a DSS validator. More...
void	init (unsigned) override
	Available examples are randomly partitioned into two independent sets according to a given percentage. More...
bool	shake (unsigned) override
	Changes the training environment. More...
virtual void	close (unsigned)
	De-initializes the data structures needed for the validation strategy. More...
virtual void	init (unsigned)=0
	Initializes the data structures needed for the validation strategy. More...
virtual bool	shake (unsigned)
	Changes the training environment. More...

Detailed Description

Dynamic training Subset Selection.

When using GP on a difficult problem, with a large set of training data, a large population size is needed and a very large number of evaluations must be carried out. DSS is a subset selection method which uses the available information to select:

• firstly 'difficult' cases;
• secondly cases which have not been looked at for several generations.

See also

• https://github.com/morinim/vita/wiki/bibliography#5
• https://github.com/morinim/vita/wiki/validation#dss

Definition at line 37 of file dss.h.

Constructor & Destructor Documentation

dss()

vita::dss::dss	(	src_problem &	prob,
		cached_evaluator &	eva_t,
		cached_evaluator &	eva_v
	)

Sets up a DSS validator.

Parameters

[in]	prob	current problem
[in]	eva_t	active training evaluator
[in]	eva_v	active validation evaluator

Note

References to the evaluator are required since (possible) cached values must be cleared when changing the training / validation set.

Definition at line 41 of file dss.cc.

Member Function Documentation

close()

void vita::dss::close ( unsigned  )

overridevirtual

Moves all the example in the validation set.

Reimplemented from vita::validation_strategy.

Definition at line 207 of file dss.cc.

init()

void vita::dss::init ( unsigned  )

overridevirtual

Available examples are randomly partitioned into two independent sets according to a given percentage.

Attention

The procedure changes the current training / validation sets.

Implements vita::validation_strategy.

Definition at line 104 of file dss.cc.

shake()

bool vita::dss::shake ( unsigned  )

overridevirtual

Changes the training environment.

Returns

true if the training environment has changed

By default does nothing, signalling that nothing is changed.

Note

Called at the beginning of every generation (multiple times per run).

Reimplemented from vita::validation_strategy.

Definition at line 174 of file dss.cc.

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

• dss.h
• dss.cc