Package org.tribuo.common.nearest

Class KNNModel<T extends Output<T>>

java.lang.Object
org.tribuo.Model<T>
org.tribuo.common.nearest.KNNModel<T>
All Implemented Interfaces:
com.oracle.labs.mlrg.olcut.provenance.Provenancable<ModelProvenance>, Serializable
public class KNNModel<T extends Output<T>> extends Model<T>
A k-nearest neighbours model.

Note multi-threaded prediction uses a ForkJoinPool which requires that the Tribuo codebase is given the "modifyThread" and "modifyThreadGroup" privileges when running under a SecurityManager.

See Also:

  • Method Details

    • predict

      public Prediction<T> predict(Example<T> example)
      Description copied from class: Model
      Uses the model to predict the output for a single example.

      predict does not mutate the example.

      Throws IllegalArgumentException if the example has no features or no feature overlap with the model.

      Specified by:
      predict in class Model<T extends Output<T>>
      Parameters:
      example - the example to predict.
      Returns:
      the result of the prediction.

    • innerPredict

      protected List<Prediction<T>> innerPredict(Iterable<Example<T>> examples)
      Uses the model to predict the output for multiple examples.
      Overrides:
      innerPredict in class Model<T extends Output<T>>
      Parameters:
      examples - the examples to predict.
      Returns:
      the results of the prediction, in the same order as the examples.

    • getTopFeatures

      public Map<String,List<com.oracle.labs.mlrg.olcut.util.Pair<String,Double>>> getTopFeatures(int n)
      Description copied from class: Model
      Gets the top n features associated with this model.

      If the model does not produce per output feature lists, it returns a map with a single element with key Model.ALL_OUTPUTS.

      If the model cannot describe it's top features then it returns Collections.emptyMap().

      Specified by:
      getTopFeatures in class Model<T extends Output<T>>
      Parameters:
      n - the number of features to return. If this value is less than 0, all features should be returned for each class, unless the model cannot score it's features.
      Returns:
      a map from string outputs to an ordered list of pairs of feature names and weights associated with that feature in the model

    • getExcuse

      public Optional<Excuse<T>> getExcuse(Example<T> example)
      Description copied from class: Model
      Generates an excuse for an example.

      This attempts to explain a classification result. Generating an excuse may be quite an expensive operation.

      This excuse either contains per class information or an entry with key Model.ALL_OUTPUTS.

      The optional is empty if the model does not provide excuses.

      Specified by:
      getExcuse in class Model<T extends Output<T>>
      Parameters:
      example - The input example.
      Returns:
      An optional excuse object. The optional is empty if this model does not provide excuses.

    • copy

      protected KNNModel<T> copy(String newName, ModelProvenance newProvenance)
      Description copied from class: Model
      Copies a model, replacing its provenance and name with the supplied values.

      Used to provide the provenance removal functionality.

      Specified by:
      copy in class Model<T extends Output<T>>
      Parameters:
      newName - The new name.
      newProvenance - The new provenance.
      Returns:
      A copy of the model.