Most-popular item recommender More...

Inheritance diagram for MostPopular:

Public Member Functions
override void	AddFeedback (ICollection< Tuple< int, int >> feedback)
	Add positive feedback events and perform incremental training More...

virtual bool	CanPredict (int user_id, int item_id)
	Check whether a useful prediction (i.e. not using a fallback/default answer) can be made for a given user-item combination More...

Object	Clone ()
	create a shallow copy of the object More...

override void	LoadModel (string filename)
	Get the model parameters from a file More...

	MostPopular ()
	Default constructor More...

override float	Predict (int user_id, int item_id)
	Predict rating or score for a given user-item combination More...

IList< Tuple< int, float > >	Recommend (int user_id, int n=-1, ICollection< int > ignore_items=null, ICollection< int > candidate_items=null)
	Recommend items for a given user More...

virtual System.Collections.Generic.IList< Tuple< int, float > >	Recommend (int user_id, int n=-1, System.Collections.Generic.ICollection< int > ignore_items=null, System.Collections.Generic.ICollection< int > candidate_items=null)

override void	RemoveFeedback (ICollection< Tuple< int, int >> feedback)
	Remove all feedback events by the given user-item combinations More...

override void	RemoveItem (int item_id)
	Remove all feedback by one item More...

override void	RemoveUser (int user_id)
	Remove all feedback by one user More...

override void	SaveModel (string filename)
	Save the model parameters to a file More...

override string	ToString ()
	Return a string representation of the recommender More...

override void	Train ()
	Learn the model parameters of the recommender from the training data More...

Protected Member Functions
override void	AddItem (int item_id)

virtual void	AddUser (int user_id)

Properties
bool	ByUser `[get, set]`
	If true, the popularity of an item is measured by the number of unique users that have accessed it. If false, the popularity is measured by the number of accesses to the item. More...

virtual IPosOnlyFeedback	Feedback `[get, set]`
	the feedback data to be used for training More...

int	MaxItemID `[get, set]`
	Maximum item ID More...

int	MaxUserID `[get, set]`
	Maximum user ID More...

bool	UpdateItems `[get, set]`

bool	UpdateUsers `[get, set]`

Detailed Description

Most-popular item recommender

Items are weighted by how often they have been seen in the past.

This method is not personalized.

This recommender supports incremental updates.

Constructor & Destructor Documentation

MostPopular ( )

inline

Default constructor

Member Function Documentation

override void AddFeedback ( ICollection< Tuple< int, int >> feedback )

inlinevirtual

Add positive feedback events and perform incremental training

Parameters

feedback collection of user id - item id tuples

Reimplemented from IncrementalItemRecommender.

virtual bool CanPredict	(	int	user_id,
		int	item_id
	)

inlinevirtualinherited

Check whether a useful prediction (i.e. not using a fallback/default answer) can be made for a given user-item combination

It is up to the recommender implementor to decide when a prediction is useful, and to document it accordingly.

Parameters

user_id	the user ID
item_id	the item ID

Returns: true if a useful prediction can be made, false otherwise

Implements IRecommender.

Reimplemented in ExternalItemRecommender, ExternalRatingPredictor, BiPolarSlopeOne, SlopeOne, Constant, GlobalAverage, UserAverage, ItemAverage, and Random.

Object Clone ( )

inlineinherited

create a shallow copy of the object

override void LoadModel ( string filename )

inlinevirtual

Get the model parameters from a file

Parameters

filename the name of the file to read from

Reimplemented from Recommender.

override float Predict	(	int	user_id,
		int	item_id
	)

inlinevirtual

Predict rating or score for a given user-item combination

Parameters

user_id	the user ID
item_id	the item ID

Returns: the predicted score/rating for the given user-item combination

Implements Recommender.

IList<Tuple<int, float> > Recommend	(	int	user_id,
		int	n = `-1`,
		ICollection< int >	ignore_items = `null`,
		ICollection< int >	candidate_items = `null`
	)

inherited

Recommend items for a given user

Parameters

user_id	the user ID
n	the number of items to recommend, -1 for as many as possible
ignore_items	collection if items that should not be returned; if null, use empty collection
candidate_items	the candidate items to choose from; if null, use all items

Returns: a sorted list of (item_id, score) tuples

Implemented in WeightedEnsemble, and Ensemble.

override void RemoveFeedback ( ICollection< Tuple< int, int >> feedback )

inlinevirtual

Remove all feedback events by the given user-item combinations

Parameters

feedback collection of user id - item id tuples

Reimplemented from IncrementalItemRecommender.

override void RemoveItem ( int item_id )

inlinevirtual

Remove all feedback by one item

Parameters

item_id the item ID

Reimplemented from IncrementalItemRecommender.

override void RemoveUser ( int user_id )

inlinevirtual

Remove all feedback by one user

Parameters

user_id the user ID

Reimplemented from IncrementalItemRecommender.

override void SaveModel ( string filename )

inlinevirtual

Save the model parameters to a file

Parameters

filename the name of the file to write to

Reimplemented from Recommender.

override string ToString ( )

inline

Return a string representation of the recommender

The ToString() method of recommenders should list the class name and all hyperparameters, separated by space characters.

Implements IRecommender.

override void Train ( )

inlinevirtual

Learn the model parameters of the recommender from the training data

Implements Recommender.

Property Documentation

bool ByUser

getset

If true, the popularity of an item is measured by the number of unique users that have accessed it. If false, the popularity is measured by the number of accesses to the item.

virtual IPosOnlyFeedback Feedback

getsetinherited

the feedback data to be used for training

int MaxItemID

getsetinherited

Maximum item ID

int MaxUserID

getsetinherited

Maximum user ID

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

MostPopular.cs

Public Member Functions

Protected Member Functions

Properties

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation

Property Documentation