public interface UserSimilarity extends Refreshable
Implementations of this interface define a notion of similarity between two users. Implementations should return values in the range -1.0 to 1.0, with 1.0 representing perfect similarity.
ItemSimilarity
Modifier and Type | Method and Description |
---|---|
void |
setPreferenceInferrer(PreferenceInferrer inferrer)
Attaches a
PreferenceInferrer to the UserSimilarity implementation. |
double |
userSimilarity(long userID1,
long userID2)
Returns the degree of similarity, of two users, based on the their preferences.
|
refresh
double userSimilarity(long userID1, long userID2) throws TasteException
Returns the degree of similarity, of two users, based on the their preferences.
userID1
- first user IDuserID2
- second user IDDouble.NaN
similarity is unknownNoSuchUserException
- if either user is known to be non-existent in the dataTasteException
- if an error occurs while accessing the datavoid setPreferenceInferrer(PreferenceInferrer inferrer)
Attaches a PreferenceInferrer
to the UserSimilarity
implementation.
inferrer
- PreferenceInferrer
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