Hi,
I'm using a version of mahout prior to MAHOUT_150, since the changes after
that version were too big.
I'm having a problem with an evaluation class
(GenericRecommenderIRStatsEvaluator): it always returns precision and recall
as NaN values. I'm using a c# port of mahout so I can't run a detailed debug
and understand what is wrong, but from some experiments I understood it
never calls my recommender (it obtains data of each user, calculate their
neighborhood and that's all).
Here is some code I'm using:
GenericRecommenderIRStatsEvaluator evaluator = new
GenericRecommenderIRStatsEvaluator();
MyDataSource source = new MyDataSource(); //a jdbc data source
ConnectionPoolDataSource poolSource = new ConnectionPoolDataSource(source);
DataModel model = new MyDataModel(poolSource, "iscrizioni", "studentID",
"ofalID", "score");
//builder is a RecommenderBuilder that returns my
UserRecommender
IRStatistics statistics = evaluator.evaluate(builder, model, null, 5,
Double.NegativeInfinity, 0.5);
string results = "Precision:" + statistics.getPrecision() + " Recall" +
statistics.getRecall();
Console.WriteLine("results:" + results);
My recommender has always worked, so I don't think it's its fault.
Thanks in advance
