org.grouplens.lenskit.baseline

Class ConstantPredictor

java.lang.Object

org.grouplens.lenskit.baseline.AbstractBaselinePredictor

org.grouplens.lenskit.baseline.ConstantPredictor

All Implemented Interfaces:

Serializable, BaselinePredictor

Direct Known Subclasses:

GlobalMeanPredictor

@Shareable
@Singleton
public class ConstantPredictor
extends AbstractBaselinePredictor

Rating scorer that predicts a constant rating for all items.

Author:

GroupLens Research

See Also:

Serialized Form

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static interface	ConstantPredictor.Value Parameter: the value used by the constant scorer.

Constructor Summary

Constructors

Constructor and Description
ConstantPredictor(double val) Construct a new constant scorer.

Method Summary

Methods

Modifier and Type	Method and Description
void	predict(long user, MutableSparseVector output, boolean predictSet) Predict method that scores into an existing mutable sparse vector.
String	toString()

Methods inherited from class org.grouplens.lenskit.baseline.AbstractBaselinePredictor

predict, predict, predict, predict, predict

Methods inherited from class java.lang.Object

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

Constructor Detail

ConstantPredictor

@Inject
public ConstantPredictor(@ConstantPredictor.Value
                        double val)

Construct a new constant scorer. This is exposed so other code can use it as a fallback.

Parameters:

val - The value to use.

Method Detail

predict

public void predict(long user,
           MutableSparseVector output,
           boolean predictSet)

Description copied from interface: BaselinePredictor

Predict method that scores into an existing mutable sparse vector.

Parameters:

user - The user ID.

output - The output vector. All items in the key domain are scored

predictSet - If true, predict all items; otherwise, only predict items that are not set..

See Also:

RatingPredictor.score(UserHistory, MutableSparseVector)

toString

public String toString()

Overrides:

toString in class Object