org.lenskit.transform.normalize

Class BiasItemVectorNormalizer

java.lang.Object

org.lenskit.transform.normalize.AbstractItemVectorNormalizer

org.lenskit.transform.normalize.BiasItemVectorNormalizer

All Implemented Interfaces:

ItemVectorNormalizer

public class BiasItemVectorNormalizer
extends AbstractItemVectorNormalizer

Item vector normalizer that subtracts user-item biases.

Constructor Summary

Constructors

Constructor and Description
BiasItemVectorNormalizer(BiasModel bias) Construct a new normalizer.

Method Summary

Modifier and Type	Method and Description
InvertibleFunction<Long2DoubleMap,Long2DoubleMap>	makeTransformation(long itemId, Long2DoubleMap vector) Make a vector transformation for a item.
VectorTransformation	makeTransformation(long itemId, SparseVector vector) Make a vector transformation for an item.

Methods inherited from class org.lenskit.transform.normalize.AbstractItemVectorNormalizer

normalize

Methods inherited from class java.lang.Object

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

Constructor Detail

BiasItemVectorNormalizer

@Inject
public BiasItemVectorNormalizer(BiasModel bias)

Construct a new normalizer.

Parameters:

bias - The bias model to subtract from item vector values.

Method Detail

makeTransformation

public VectorTransformation makeTransformation(long itemId,
                                               SparseVector vector)

Description copied from interface: ItemVectorNormalizer

Make a vector transformation for an item. The resulting transformation will be applied to item vectors to normalize and denormalize them.

Parameters:

itemId - The item id to normalize for.

vector - The item’s vector to use as the reference vector.

Returns:

The vector transformaition normalizing for this item.

makeTransformation

public InvertibleFunction<Long2DoubleMap,Long2DoubleMap> makeTransformation(long itemId,
                                                                            Long2DoubleMap vector)

Description copied from interface: ItemVectorNormalizer

Make a vector transformation for a item. The resulting transformation will be applied to item vectors to normalize and denormalize them.

Parameters:

itemId - The item ID to normalize for.

vector - The item’s vector to use as the reference vector.

Returns:

The vector transformation normalizing for this item.