edu.byu.nlp.al.EmpiricalAnnotationInstanceManager.java Source code

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Here is the source code for edu.byu.nlp.al.EmpiricalAnnotationInstanceManager.java

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/**
 * Copyright 2012 Brigham Young University
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package edu.byu.nlp.al;

import java.util.ArrayDeque;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Deque;
import java.util.List;
import java.util.concurrent.TimeUnit;

import org.apache.commons.math3.random.RandomGenerator;

import com.google.common.annotations.VisibleForTesting;
import com.google.common.collect.Lists;

import edu.byu.nlp.data.FlatInstance;
import edu.byu.nlp.data.measurements.ClassificationMeasurements.BasicClassificationLabelProportionMeasurement;
import edu.byu.nlp.data.types.Dataset;
import edu.byu.nlp.data.types.Measurement;
import edu.byu.nlp.data.types.SparseFeatureVector;
import edu.byu.nlp.data.util.EmpiricalAnnotations;
import edu.byu.nlp.dataset.Datasets;
import edu.byu.nlp.util.Deques;

/**
 * An InstanceProvider that reveals existing annotations based on their timestamps so 
 * that order they were collected is preserved. 
 * 
 * @author pfelt
 *
 */
public class EmpiricalAnnotationInstanceManager<D, L> extends AbstractInstanceManager<D, L>
        implements InstanceManager<D, L> {

    private List<FlatInstance<D, L>> queue;

    @VisibleForTesting
    EmpiricalAnnotationInstanceManager(Iterable<FlatInstance<D, L>> instances,
            EmpiricalAnnotations<D, L> annotations, AnnotationRecorder<D, L> annotationRecorder,
            int maxNumAnnotations, int maxNumMeasurements, boolean prioritizeLabelProportions,
            RandomGenerator rnd) {
        super(annotationRecorder);

        List<FlatInstance<D, L>> sortedAnnotations = Lists.newArrayList();
        for (FlatInstance<D, L> inst : instances) {
            // add each annotation associated with this item to the queue 
            sortedAnnotations.addAll(annotations.getAnnotationsFor(inst.getSource(), inst.getData()).values());
        }
        // sort the annotation queue based on annotation order
        Datasets.sortAnnotationsInPlace(sortedAnnotations);

        // interleave measurements and annotations
        Deque<FlatInstance<D, L>> measurementDeque = Deques.randomizedDeque(annotations.getMeasurements(), rnd);
        prioritizeMeasurements(measurementDeque, prioritizeLabelProportions);
        Deque<FlatInstance<D, L>> annotationDeque = new ArrayDeque<FlatInstance<D, L>>(sortedAnnotations);
        queue = Lists.newLinkedList(); // better queueing behavior

        // add measurements 
        int numMeasurements = 0;
        while (measurementDeque.size() > 0 && numMeasurements < maxNumMeasurements) {
            numMeasurements += 1;
            queue.add(measurementDeque.pop());
        }

        // add annotations 
        int numAnnotations = 0;
        while (annotationDeque.size() > 0 && numAnnotations < maxNumAnnotations) {
            numAnnotations += 1;
            queue.add(annotationDeque.pop());
        }
    }

    @Override
    public FlatInstance<D, L> instanceFor(int annotatorId, long timeout, TimeUnit timeUnit)
            throws InterruptedException {
        if (queue.size() > 0) {
            // get next most recent annotation in the queue
            FlatInstance<D, L> nextann = queue.get(0);

            // if it belongs to annotatorId, return it
            if (nextann.getAnnotator() == annotatorId) {
                queue.remove(nextann);
                return nextann;
            }
        }

        // return null if annotatorId is not the next one who historically 
        // gave an annotation.
        // This strategy of try+fail will incur a time cost,
        // but the learning curve driver class grabs random 
        // annotators as quickly as it can and there aren't usually too many, 
        // so the penalty won't be too severe
        return null;
    }

    @Override
    public Collection<FlatInstance<D, L>> getAllInstances() {
        return queue;
    }

    /** {@inheritDoc} */
    @Override
    public boolean isDone() {
        return queue.size() == 0;
    }

    public static EmpiricalAnnotationInstanceManager<SparseFeatureVector, Integer> newManager(Dataset dataset,
            EmpiricalAnnotations<SparseFeatureVector, Integer> annotations, int maxNumAnnotations,
            int maxNumMeasurements, boolean prioritizeLabelProportions, RandomGenerator rnd) {

        List<FlatInstance<SparseFeatureVector, Integer>> instances = Datasets.instancesIn(dataset);
        return new EmpiricalAnnotationInstanceManager<SparseFeatureVector, Integer>(instances, annotations,
                new DatasetAnnotationRecorder(dataset), maxNumAnnotations, maxNumMeasurements,
                prioritizeLabelProportions, rnd);
    }

    private void prioritizeMeasurements(Deque<FlatInstance<D, L>> measurementDeque,
            boolean prioritizeLabelProportions) {
        if (prioritizeLabelProportions) {
            // get a list of all the labeled proportion measurements 
            ArrayList<FlatInstance<D, L>> proportions = Lists.newArrayList();
            for (FlatInstance<D, L> inst : measurementDeque) {
                Measurement meas = inst.getMeasurement();
                if (meas instanceof BasicClassificationLabelProportionMeasurement) {
                    proportions.add(inst);
                }
            }
            // move them to the front of the line
            measurementDeque.removeAll(proportions);
            for (FlatInstance<D, L> prop : proportions) {
                measurementDeque.push(prop);
            }
        }
    }

}