GenericItemBasedRecommender ClassNReco.Recommender Class Library

A simple IRecommender which uses a given IDataModel and IItemSimilarity to produce recommendations. This class represents Taste's support for item-based recommenders.

The IItemSimilarity is the most important point to discuss here. Item-based recommenders are useful because they can take advantage of something to be very fast: they base their computations on item similarity, not user similarity, and item similarity is relatively static. It can be precomputed, instead of re-computed in real time.

Thus it's strongly recommended that you use GenericItemSimilarity with pre-computed similarities if you're going to use this class. You can use PearsonCorrelationSimilarity too, which computes similarities in real-time, but will probably find this painfully slow for large amounts of data.

Inheritance Hierarchy

System Object
  NReco.CF.Taste.Impl.Recommender AbstractRecommender
    NReco.CF.Taste.Impl.Recommender GenericItemBasedRecommender
      NReco.CF.Taste.Impl.Recommender GenericBooleanPrefItemBasedRecommender

Namespace: NReco.CF.Taste.Impl.Recommender
Assembly: NReco.Recommender (in NReco.Recommender.dll) Version: (

public class GenericItemBasedRecommender : AbstractRecommender, 
	IItemBasedRecommender, IRecommender, IRefreshable

The GenericItemBasedRecommender type exposes the following members.


Public methodGenericItemBasedRecommender(IDataModel, IItemSimilarity)
Initializes a new instance of the GenericItemBasedRecommender class
Public methodGenericItemBasedRecommender(IDataModel, IItemSimilarity, ICandidateItemsStrategy, IMostSimilarItemsCandidateItemsStrategy)
Initializes a new instance of the GenericItemBasedRecommender class

Protected methoddoEstimatePreference
Public methodEquals
Determines whether the specified Object is equal to the current Object.
(Inherited from Object.)
Public methodEstimatePreference (Overrides AbstractRecommender EstimatePreference(Int64, Int64).)
Protected methodFinalize
Allows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection.
(Inherited from Object.)
Protected methodGetAllOtherItems (Inherited from AbstractRecommender.)
Public methodGetDataModel (Inherited from AbstractRecommender.)
Protected methodStatic membergetDefaultMostSimilarItemsCandidateItemsStrategy
Public methodGetHashCode
Serves as a hash function for a particular type.
(Inherited from Object.)
Public methodgetSimilarity
Public methodGetType
Gets the Type of the current instance.
(Inherited from Object.)
Protected methodMemberwiseClone
Creates a shallow copy of the current Object.
(Inherited from Object.)
Public methodMostSimilarItems(Int64, Int32)
Public methodMostSimilarItems( Int64 , Int32)
Public methodMostSimilarItems(Int64, Int32, IRescorer Tuple Int64, Int64  )
Public methodMostSimilarItems( Int64 , Int32, IRescorer Tuple Int64, Int64  )
Public methodMostSimilarItems( Int64 , Int32, Boolean)
Public methodMostSimilarItems( Int64 , Int32, IRescorer Tuple Int64, Int64  , Boolean)
Public methodRecommend(Int64, Int32) (Inherited from AbstractRecommender.)
Public methodRecommend(Int64, Int32, IDRescorer) (Overrides AbstractRecommender Recommend(Int64, Int32, IDRescorer).)
Public methodRecommendedBecause
Public methodRefresh (Overrides AbstractRecommender Refresh(IList IRefreshable ).)
Public methodRemovePreference (Inherited from AbstractRecommender.)
Public methodSetPreference (Inherited from AbstractRecommender.)
Public methodToString (Overrides Object ToString .)
See Also