/// <summary>
/// Predict the rating of the item by users
/// </summary>
private static void PredictRating(string[] args)
{
Console.WriteLine("Predicting ratings for Users...");
String outputFile = Path.Combine(args[2], outputFileForRatings);
testingFile = Path.Combine(args[1], testingFile);
testingFileModified = Path.Combine(args[2], testingFileModified);
ModifyTestingFileForRating(testingFile, testingFileModified);
float minRating = 1;
float maxRating = 5;
var userMapping = new Mapping();
var itemMapping = new Mapping();
var trainingData = StaticRatingData.Read(trainingCompactFileForRatings, userMapping, itemMapping, RatingType.FLOAT, TestRatingFileFormat.WITH_RATINGS, false);
var testUsers = trainingData.AllUsers; // users that will be taken into account in the evaluation
var candidate_items = trainingData.AllItems; // items that will be taken into account in the evaluation
var testData = StaticRatingData.Read(testingFileModified, userMapping, itemMapping, RatingType.FLOAT, TestRatingFileFormat.WITH_RATINGS, false);
var recommender = new BiasedMatrixFactorization();
recommender.MinRating = minRating;
recommender.MaxRating = maxRating;
recommender.Ratings = trainingData;
recommender.NumFactors = 30;
recommender.NumIter = 100;
recommender.RegI = 0.04F;
recommender.RegU = 0.04F;
//recommender.BiasReg = 0.09F;
recommender.FrequencyRegularization = true;
recommender.BoldDriver = true;
recommender.LearnRate = 0.07F;
Stopwatch timeKeeper = new Stopwatch();
timeKeeper.Start();
recommender.Train();
timeKeeper.Stop();
Console.WriteLine("time passed for training rating prediction model: " + timeKeeper.ElapsedMilliseconds);
// measure the accuracy on the test data set
timeKeeper = new Stopwatch();
timeKeeper.Start();
var results = recommender.Evaluate(testData);
timeKeeper.Stop();
Console.WriteLine("time passed for rating prediction: " + timeKeeper.ElapsedMilliseconds);
Console.WriteLine("RMSE={0}", results["RMSE"]);
recommender.WritePredictions(testData, outputFile, userMapping, itemMapping, "{0}-{1},{2}", "userID-itemID,rating");
}
public void TestRead()
{
var reader = new StringReader(@"5951,50,5,2001-01-01
5951,223,5,2001-01-01
5951,260,5,2001-01-01
5951,293,5,2001-01-01
5951,356,4,2001-01-01
5951,364,3,2001-01-01
5951,457,3,2001-01-01
");
IRatings data = StaticRatingData.Read(reader, 7);
Assert.AreEqual(7, data.Count);
}
public void TestReadIgnoreLine()
{
var reader = new StringReader(@"# first line
5951,50,5,2001-01-01 00:00:00
5951,223,5,2001-01-01 00:00:00
5951,260,5,2001-01-01 00:00:00
5951,293,5,2001-01-01 00:00:00
5951,356,4,2001-01-01 00:00:00
5951,364,3,2001-01-01 00:00:00
5951,457,3,2001-01-01 00:00:00
");
IRatings data = StaticRatingData.Read(reader, 7, null, null, RatingType.FLOAT, TestRatingFileFormat.WITH_RATINGS, true);
Assert.AreEqual(7, data.Count);
}
protected override void LoadData()
{
bool static_data = !online_eval;
TimeSpan loading_time = Wrap.MeasureTime(delegate() {
base.LoadData();
// read training data
if ((recommender is TimeAwareRatingPredictor || chronological_split != null) && file_format != RatingFileFormat.MOVIELENS_1M)
{
training_data = TimedRatingData.Read(training_file, user_mapping, item_mapping);
}
else
{
if (file_format == RatingFileFormat.DEFAULT)
{
training_data = static_data
? StaticRatingData.Read(training_file, user_mapping, item_mapping, rating_type)
: RatingData.Read(training_file, user_mapping, item_mapping);
}
else if (file_format == RatingFileFormat.IGNORE_FIRST_LINE)
{
training_data = static_data
? StaticRatingData.Read(training_file, user_mapping, item_mapping, rating_type, TestRatingFileFormat.WITH_RATINGS, true)
: RatingData.Read(training_file, user_mapping, item_mapping, true);
}
else if (file_format == RatingFileFormat.MOVIELENS_1M)
{
training_data = MovieLensRatingData.Read(training_file, user_mapping, item_mapping);
}
else if (file_format == RatingFileFormat.KDDCUP_2011)
{
training_data = MyMediaLite.IO.KDDCup2011.Ratings.Read(training_file);
}
}
recommender.Ratings = training_data;
// read test data
if (test_file != null)
{
TestRatingFileFormat test_format = test_no_ratings ? TestRatingFileFormat.WITHOUT_RATINGS : TestRatingFileFormat.WITH_RATINGS;
if (recommender is TimeAwareRatingPredictor && file_format != RatingFileFormat.MOVIELENS_1M)
{
test_data = TimedRatingData.Read(test_file, user_mapping, item_mapping, test_format);
}
else if (file_format == RatingFileFormat.MOVIELENS_1M)
{
test_data = MovieLensRatingData.Read(test_file, user_mapping, item_mapping, test_format);
}
else if (file_format == RatingFileFormat.KDDCUP_2011)
{
test_data = MyMediaLite.IO.KDDCup2011.Ratings.Read(test_file);
}
else
{
test_data = StaticRatingData.Read(test_file, user_mapping, item_mapping, rating_type, test_format, file_format == RatingFileFormat.IGNORE_FIRST_LINE);
}
if (recommender is ITransductiveRatingPredictor)
{
((ITransductiveRatingPredictor)recommender).AdditionalFeedback = test_data;
}
}
});
Console.Error.WriteLine(string.Format(CultureInfo.InvariantCulture, "loading_time {0:0.##}", loading_time.TotalSeconds));
Console.Error.WriteLine("memory {0}", Memory.Usage);
}