public void Evaluate(EvalutationContext <ItemRanking> context)
{
if (!(context is ItemRankingEvaluationContext))
{
throw new Exception("Wrong evaluation context.");
}
var dataset = context.Dataset;
var model = (IPredictor <ItemRanking>)context.Model;
// make sure the model is trained
if (!model.IsTrained)
{
model.Train(dataset.TrainSamples);
}
var mapper = (IUserItemMapper)context.Model;
var testset = dataset.TestSamples.ToPosOnlyFeedback(mapper.UsersMap, mapper.ItemsMap);
var trainset = dataset.TrainSamples.ToPosOnlyFeedback(mapper.UsersMap, mapper.ItemsMap);
var results = _recommender.Evaluate(testset, trainset);
foreach (var item in results)
{
context[item.Key] = item.Value;
Console.WriteLine(string.Format("{0}: {1:0.0000}", item.Key, item.Value));
}
// calculate F1@5 and F1@10
var precAt5 = (float)context["prec@5"];
var precAt10 = (float)context["prec@5"];
var recallAt5 = (float)context["recall@5"];
var recallAt10 = (float)context["recall@10"];
var f1At5 = precAt5 * recallAt5 * 2 / (precAt5 + recallAt5);
var f1At10 = precAt10 * recallAt10 * 2 / (precAt10 + recallAt10);
Console.WriteLine(string.Format("F1@5: {0:0.0000}", f1At5));
Console.WriteLine(string.Format("F1@10: {0:0.0000}", f1At10));
}
public void Evaluate(EvalutationContext <PositiveFeedback> context)
{
var model = (IPredictor <PositiveFeedback>)context.Model;
var trainSet = context.Splitter.Train;
var tesSet = context.Splitter.Test;
// make sure the model is trained
if (!model.IsTrained)
{
model.Train(trainSet);
}
var mapper = (IUserItemMapper)context.Model;
var testset = tesSet.ToPosOnlyFeedback(mapper.UsersMap, mapper.ItemsMap);
var trainset = trainSet.ToPosOnlyFeedback(mapper.UsersMap, mapper.ItemsMap);
var results = _recommender.Evaluate(testset, trainset);
foreach (var item in results)
{
context[item.Key] = item.Value;
Console.WriteLine(string.Format("{0}: {1:0.0000}", item.Key, item.Value));
}
// calculate F1@5 and F1@10
var precAt5 = (float)context["prec@5"];
var precAt10 = (float)context["prec@5"];
var recallAt5 = (float)context["recall@5"];
var recallAt10 = (float)context["recall@10"];
var f1At5 = precAt5 * recallAt5 * 2 / (precAt5 + recallAt5);
var f1At10 = precAt10 * recallAt10 * 2 / (precAt10 + recallAt10);
Console.WriteLine(string.Format("F1@5: {0:0.0000}", f1At5));
Console.WriteLine(string.Format("F1@10: {0:0.0000}", f1At10));
}
