public override void Test()
{
var recommender = (TRecommender)Activator.CreateInstance(typeof(TRecommender), new object[] { Sim, Rg, K });
TestName = string.Format("Knn-K{0}-{1}-{2}-{3}-T{4}", K, Sim, Rg, recommender, NumberOfTests);
writeFrequency = (int)Math.Ceiling(NumberOfTests / 100d);
base.Test();
try
{
Write(string.Format("Test {0} ({1})", TestName, DateTime.Now));
Write("------------------------------------------------------", false);
rs = new SimpleKnnRecommendationSystem(Trainer, recommender);
Timer.Restart();
MaeBiasAndVariance[] mbvsByRatings;
var mbv = TestRecommendationSystem(out mbvsByRatings);
Timer.Stop();
Write("------------------------------------------------------", false);
for (var i = 0; i < mbvsByRatings.Length; i++)
{
Write(string.Format(CultureInfo.InvariantCulture, "{0}\t->\tRating:{1}\t{2}.", TestName, i + 1, mbvsByRatings[i]));
}
Write(string.Format(CultureInfo.InvariantCulture, "{0}\t->\tAll ratings\t{1}\t({2}).", TestName, mbv, TimeSpan.FromMilliseconds(Timer.ElapsedMilliseconds)));
}
catch (Exception e)
{
Write(string.Format(CultureInfo.InvariantCulture, "{0}{1}{1}{2}", e, Environment.NewLine, e.Message));
}
FileWriter.Close();
}
private MaeAndBias TestRecommendationSystem <TModel, TUser>(IRecommendationSystem <TModel, TUser, ITrainer <TModel>, IRecommender <TModel> > rs, IEnumerable <TUser> testUsers, TModel model, List <IArtist> artists)
where TModel : IModel
where TUser : IUser
{
var maeList = new List <float>();
var biasList = new List <float>();
foreach (var user in TestUsers)
{
lock (user)
{
var originalRatings = user.Ratings;
foreach (var rating in user.Ratings)
{
user.Ratings = originalRatings.Where(r => r != rating).ToList();
var predictedRating = rs.Recommender.PredictRatingForArtist(user, model, artists, rating.ArtistIndex);
var error = predictedRating - rating.Value;
biasList.Add(error);
maeList.Add((float)Math.Sqrt(error * error));
}
user.Ratings = originalRatings;
}
}
return(new MaeAndBias(maeList, biasList));
}
public SvdTester(string testName, IRecommendationSystem <TSvdModel, IUser, ISvdTrainer <TSvdModel>, ISvdRecommender <TSvdModel> > recommendationSystem, TSvdModel model, List <IUser> testUsers, List <IRating> testRatings, List <IArtist> artists)
{
RecommendationSystem = recommendationSystem;
Model = model;
TestUsers = testUsers;
TestRatings = testRatings;
Artists = artists;
TestName = testName;
}
