/// <summary>
/// Constructs an active learning instance with a specified data set and model instance.
/// </summary>
/// <param name="data">The data.</param>
/// <param name="model">The model instance.</param>
/// <param name="results">The results instance.</param>
/// <param name="numCommunities">The number of communities (only for CBCC).</param>
public ActiveLearning(IList <Datum> data, BCC model, Results results, int numCommunities)
{
this.bcc = model;
CommunityModel communityModel = model as CommunityModel;
IsCommunityModel = (communityModel != null);
ActiveLearningResults = results;
BatchResults = results;
WorkerIds = ActiveLearningResults.Mapping.WorkerIdToIndex.Keys.ToArray();
TaskIds = ActiveLearningResults.Mapping.TaskIdToIndex.Keys.ToArray();
/// Builds the full matrix of data from every task and worker
PredictionData = new List <Datum>();
foreach (var workerId in WorkerIds)
{
foreach (var task in TaskIds)
{
PredictionData.Add(new Datum
{
TaskId = task,
WorkerId = workerId,
WorkerLabel = 0,
GoldLabel = null
});
}
}
}
/// <summary>
/// Runs the BCC or CBCC model.
/// </summary>
/// <param name="modelName">The model name.</param>
/// <param name="data">The data that will be used for this run.</param>
/// <param name="fullData">The full data set of data.</param>
/// <param name="model">The model instance (BCC or CBCC).</param>
/// <param name="mode">The mode (for example training, prediction, etc.).</param>
/// <param name="calculateAccuracy">Whether to calculate accuracy.</param>
/// <param name="numCommunities">The number of communities (community model only).</param>
/// <param name="serialize">Whether to serialize all posteriors.</param>
/// <param name="serializeCommunityPosteriors">Whether to serialize community posteriors.</param>
public void RunBCC(string modelName, IList <Datum> data, IList <Datum> fullData, BCC model, RunMode mode, bool calculateAccuracy, int numCommunities = -1, bool serialize = false, bool serializeCommunityPosteriors = false)
{
CommunityModel communityModel = model as CommunityModel;
IsCommunityModel = communityModel != null;
if (this.Mapping == null)
{
this.Mapping = new DataMapping(fullData, numCommunities);
this.GoldLabels = this.Mapping.GetGoldLabelsPerTaskId();
}
/// A new model is created if the label count or the task count has changed
bool createModel = (Mapping.LabelCount != model.LabelCount) || (Mapping.TaskCount != model.TaskCount);
if (IsCommunityModel)
{
/// Creates a new CBCC model instance
CommunityCount = numCommunities;
createModel = createModel || (numCommunities != communityModel.CommunityCount);
if (createModel)
{
communityModel.CreateModel(Mapping.TaskCount, Mapping.LabelCount, numCommunities);
}
}
else if (createModel)
{
/// Creates a new BCC model instance
model.CreateModel(Mapping.TaskCount, Mapping.LabelCount);
}
/// Selects the prior according to the run mode
BCC.Posteriors priors = null;
switch (mode)
{
/// Use existing priors
case RunMode.OnlineTraining:
case RunMode.LookAheadExperiment:
case RunMode.Prediction:
priors = ToPriors();
break;
default:
/// Use default priors
ClearResults();
if (mode == RunMode.LoadAndUseCommunityPriors && IsCommunityModel)
{
priors = DeserializeCommunityPosteriors(modelName, numCommunities);
}
break;
}
/// Get data to observe
var labelsPerWorkerIndex = Mapping.GetLabelsPerWorkerIndex(data);
if (mode == RunMode.Prediction)
{
/// Signal prediction mode by setting all labels to null
labelsPerWorkerIndex = labelsPerWorkerIndex.Select(arr => (int[])null).ToArray();
}
/// Run model inference
BCC.Posteriors posteriors = model.Infer(
Mapping.GetTaskIndicesPerWorkerIndex(data),
labelsPerWorkerIndex, priors);
UpdateResults(posteriors, mode);
/// Compute accuracy
if (calculateAccuracy)
{
UpdateAccuracy();
}
/// Serialize parameters
if (serialize)
{
using (FileStream stream = new FileStream(modelName + ".xml", FileMode.Create))
{
var serializer = new System.Xml.Serialization.XmlSerializer(IsCommunityModel ? typeof(CommunityModel.Posteriors) : typeof(BCC.Posteriors));
serializer.Serialize(stream, posteriors);
}
}
if (serializeCommunityPosteriors && IsCommunityModel)
{
SerializeCommunityPosteriors(modelName);
}
}
