burlap.behavior.singleagent.learnfromdemo.mlirl

Class MLIRLRequest

java.lang.Object

burlap.behavior.singleagent.learnfromdemo.IRLRequest

burlap.behavior.singleagent.learnfromdemo.mlirl.MLIRLRequest

Direct Known Subclasses:

MultipleIntentionsMLIRLRequest

public class MLIRLRequest
extends IRLRequest

A request object for Maximum-Likelihood Inverse Reinforcement Learning (MLIRL). This request adds a set of optionally specified weights on the expert trajectories, the DifferentiableRF to use, and the Boltzmann beta parameter used for Differentiable planning. The larger the beta value, the more deterministic the expert trajectories are assumed to be.

If no expert trajectory weights are provided, then they will all be assumed to have a weight of 1. Calls to the getEpisodeWeights() method when weights have not been specified will result in a new double array being created and returned with the value 1.0 everywhere, so changes to the returned array will not change the weights actually used. Instead, modify the weights using the setEpisodeWeights(double[]) method.

Author:

James MacGlashan.

Field Summary

Fields

Modifier and Type	Field and Description
protected double	boltzmannBeta The parameter used in the boltzmann policy that affects how noisy the expert is assumed to be.
protected double[]	episodeWeights The weight assigned to each episode.
protected DifferentiableRF	rf The differentiable reward function model that will be estimated by MLRIL.

Fields inherited from class burlap.behavior.singleagent.learnfromdemo.IRLRequest

domain, expertEpisodes, gamma, planner

Constructor Summary

Constructors

Constructor and Description
MLIRLRequest(SADomain domain, java.util.List<Episode> expertEpisodes, DifferentiableRF rf, HashableStateFactory hashingFactory) Initializes without any expert trajectory weights (which will be assumed to have a value 1) and requests a default DifferentiableQFunction instance to be created using the HashableStateFactory provided.
MLIRLRequest(SADomain domain, Planner planner, java.util.List<Episode> expertEpisodes, DifferentiableRF rf) Initializes the request without any expert trajectory weights (which will be assumed to have a value 1).

Method Summary

Modifier and Type	Method and Description
double	getBoltzmannBeta()
double[]	getEpisodeWeights() Returns expert episodes weights.
DifferentiableRF	getRf()
boolean	isValid() Returns true if this request object has valid data members set; false otherwise.
void	setBoltzmannBeta(double boltzmannBeta)
void	setEpisodeWeights(double[] episodeWeights)
void	setPlanner(Planner p)
void	setRf(DifferentiableRF rf)

Methods inherited from class burlap.behavior.singleagent.learnfromdemo.IRLRequest

getDomain, getExpertEpisodes, getGamma, getPlanner, setDomain, setExpertEpisodes, setGamma

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

episodeWeights

protected double[] episodeWeights

The weight assigned to each episode. If null, all episodes will be assumed to have equal weight

boltzmannBeta

protected double boltzmannBeta

The parameter used in the boltzmann policy that affects how noisy the expert is assumed to be. The smaller the parameter, the more noisy the expert behavior is assumed; the larger the more correct.

rf

protected DifferentiableRF rf

The differentiable reward function model that will be estimated by MLRIL.

Constructor Detail

MLIRLRequest

public MLIRLRequest(SADomain domain,
                    Planner planner,
                    java.util.List<Episode> expertEpisodes,
                    DifferentiableRF rf)

Initializes the request without any expert trajectory weights (which will be assumed to have a value 1). If the provided valueFunction is not null and does not implement the DifferentiableQFunction interface, an exception will be thrown.

Parameters:

domain - the domain in which trajectories are provided.

planner - a valueFunction that implements the DifferentiableQFunction interface.

expertEpisodes - the expert episodes/trajectories to use for training.

rf - the DifferentiableRF model to use.

MLIRLRequest

public MLIRLRequest(SADomain domain,
                    java.util.List<Episode> expertEpisodes,
                    DifferentiableRF rf,
                    HashableStateFactory hashingFactory)

Initializes without any expert trajectory weights (which will be assumed to have a value 1) and requests a default DifferentiableQFunction instance to be created using the HashableStateFactory provided. The DifferentiableQFunction instance will be a DifferentiableVI that plans either until the maximum change is the value function is no greater than 0.01 or until 500 iterations have been performed. A default gamma (discount) value of 0.99 will be used for the valueFunction and no terminal states will be used.

Parameters:

domain - the domain in which trajectories are provided.

expertEpisodes - the expert episodes/trajectories to use for training.

rf - the DifferentiableRF model to use.

hashingFactory - the state hashing factory to use for the created valueFunction.

Method Detail

isValid

public boolean isValid()

Description copied from class: IRLRequest

Returns true if this request object has valid data members set; false otherwise.

Overrides:

isValid in class IRLRequest

Returns:

true if this request object has valid data members set; false otherwise.

setPlanner

public void setPlanner(Planner p)

Overrides:

setPlanner in class IRLRequest

getEpisodeWeights

public double[] getEpisodeWeights()

Returns expert episodes weights. If no specific weights have been set, a new double array the same length as the number of expert episodes with a constant value of 1 will be created and returned.

Returns:

expert episodes weights

getBoltzmannBeta

public double getBoltzmannBeta()

getRf

public DifferentiableRF getRf()

setEpisodeWeights

public void setEpisodeWeights(double[] episodeWeights)

setBoltzmannBeta

public void setBoltzmannBeta(double boltzmannBeta)

setRf

public void setRf(DifferentiableRF rf)