示例#1
0
    static void DoTrack1()
    {
        var rating_predictor_validate = recommender as RatingPredictor;
        var rating_predictor_final    = rating_predictor_validate.Clone() as RatingPredictor;

        rating_predictor_final.Ratings = complete_ratings;

        Console.WriteLine("Validation split:");
        Utils.DisplayDataStats(training_ratings, validation_ratings, rating_predictor_validate);
        Console.WriteLine("Test split:");
        Utils.DisplayDataStats(complete_ratings, test_data, rating_predictor_final);

        if (find_iter != 0)
        {
            if (!(recommender is IIterativeModel))
            {
                Usage("Only iterative recommenders support find_iter.");
            }
            IIterativeModel iterative_recommender_validate = (MatrixFactorization)rating_predictor_validate;
            IIterativeModel iterative_recommender_final    = (MatrixFactorization)rating_predictor_final;
            Console.WriteLine(recommender.ToString() + " ");

            if (load_model_file == string.Empty)
            {
                iterative_recommender_validate.Train();
                iterative_recommender_final.Train();
            }
            else
            {
                Recommender.LoadModel(rating_predictor_final, "final-" + load_model_file);
            }

            if (compute_fit)
            {
                Console.Write(string.Format(CultureInfo.InvariantCulture, "fit {0:0.#####} ", iterative_recommender_validate.ComputeFit()));
            }

            MyMediaLite.Eval.Ratings.DisplayResults(MyMediaLite.Eval.Ratings.Evaluate(rating_predictor_validate, validation_ratings));
            Console.WriteLine(" " + iterative_recommender_validate.NumIter);

            for (int i = (int)iterative_recommender_validate.NumIter + 1; i <= max_iter; i++)
            {
                TimeSpan time = Utils.MeasureTime(delegate() {
                    iterative_recommender_validate.Iterate();

                    iterative_recommender_final.Iterate();                     // TODO parallelize this
                });
                training_time_stats.Add(time.TotalSeconds);


                if (i % find_iter == 0)
                {
                    if (compute_fit)
                    {
                        double fit = 0;
                        time = Utils.MeasureTime(delegate() {
                            fit = iterative_recommender_validate.ComputeFit();
                        });
                        fit_time_stats.Add(time.TotalSeconds);
                        Console.Write(string.Format(CultureInfo.InvariantCulture, "fit {0:0.#####} ", fit));
                    }

                    // evaluate and save stats
                    // TODO parallelize
                    Dictionary <string, double> results = null;
                    time = Utils.MeasureTime(delegate() {
                        results = MyMediaLite.Eval.Ratings.Evaluate(rating_predictor_validate, validation_ratings);
                        MyMediaLite.Eval.Ratings.DisplayResults(results);
                        rmse_eval_stats.Add(results["RMSE"]);
                        Console.WriteLine(" " + i);
                    });
                    eval_time_stats.Add(time.TotalSeconds);


                    // write out model files and predictions
                    if (save_model_file != string.Empty)
                    {
                        Recommender.SaveModel(rating_predictor_validate, save_model_file + "-validate", i);
                        Recommender.SaveModel(rating_predictor_final, save_model_file, i);
                    }
                    if (prediction_file != string.Empty)
                    {
                        if (track2)
                        {
                            KDDCup.PredictRatingsDouble(rating_predictor_validate, validation_candidates, prediction_file + "-validate-it-" + i);
                            KDDCup.PredictRatingsDouble(rating_predictor_final, test_data, prediction_file + "-it-" + i);
                        }
                        else
                        {
                            KDDCup.PredictRatings(rating_predictor_validate, validation_ratings, prediction_file + "-validate-it-" + i);
                            KDDCup.PredictRatings(rating_predictor_final, test_data, prediction_file + "-it-" + i);
                        }
                    }

                    // check whether we should abort
                    if (epsilon > 0 && results["RMSE"] > rmse_eval_stats.Min() + epsilon)
                    {
                        Console.Error.WriteLine(string.Format(CultureInfo.InvariantCulture, "{0} >> {1}", results["RMSE"], rmse_eval_stats.Min()));
                        Console.Error.WriteLine("Reached convergence on training/validation data after {0} iterations.", i);
                        break;
                    }
                    if (results["RMSE"] > rmse_cutoff || results["MAE"] > mae_cutoff)
                    {
                        Console.Error.WriteLine("Reached cutoff after {0} iterations.", i);
                        break;
                    }
                }
            }             // for

            DisplayIterationStats();
            Recommender.SaveModel(recommender, save_model_file);
        }
        else
        {
            TimeSpan seconds;

            if (!no_eval)
            {
                if (load_model_file == string.Empty)
                {
                    Console.Write(recommender.ToString());
                    if (cross_validation > 0)                     // TODO cross-validation could also be performed on the complete dataset
                    {                                             // TODO support track2
                        Console.WriteLine();
                        var split   = new RatingCrossValidationSplit(training_ratings, cross_validation);
                        var results = MyMediaLite.Eval.Ratings.EvaluateOnSplit(rating_predictor_validate, split);
                        MyMediaLite.Eval.Ratings.DisplayResults(results);
                        no_eval = true;
                        rating_predictor_validate.Ratings = training_ratings;
                    }
                    else
                    {
                        seconds = Utils.MeasureTime(delegate() { recommender.Train(); });
                        Console.Write(" training_time " + seconds + " ");
                        Recommender.SaveModel(recommender, save_model_file);
                    }
                }

                Console.Write(recommender.ToString() + " ");

                seconds = Utils.MeasureTime(
                    delegate() { MyMediaLite.Eval.Ratings.DisplayResults(MyMediaLite.Eval.Ratings.Evaluate(rating_predictor_validate, validation_ratings)); }
                    );
                Console.Write(" testing_time " + seconds);
            }

            Console.WriteLine();

            if (prediction_file != string.Empty)
            {
                Console.WriteLine("Prediction for KDD Cup Track 1:");
                seconds = Utils.MeasureTime(delegate() { rating_predictor_final.Train(); });
                Console.Write(" training_time " + seconds + " ");
                if (save_model_file != string.Empty)
                {
                    Recommender.SaveModel(rating_predictor_validate, save_model_file + "-validate");
                    Recommender.SaveModel(rating_predictor_final, save_model_file);
                }

                Console.WriteLine();
                seconds = Utils.MeasureTime(delegate() {
                    KDDCup.PredictRatingsDouble(rating_predictor_final, test_data, prediction_file);

                    if (track2)
                    {
                        KDDCup.PredictRatingsDouble(rating_predictor_validate, validation_candidates, prediction_file + "-validate");
                    }
                    else
                    {
                        KDDCup.PredictRatings(rating_predictor_validate, validation_ratings, prediction_file + "-validate");
                    }
                });
                Console.Error.WriteLine("predicting_time " + seconds);
            }
        }
    }