pmf_ratio.py

# Copyright 2018 The Cornac Authors. All Rights Reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
# ============================================================================
"""Example to run Probabilistic Matrix Factorization (PMF) model with Ratio Split evaluation strategy"""

import cornac
from cornac.datasets import movielens
from cornac.eval_methods import RatioSplit
from cornac.models import PMF


# Load the MovieLens 100K dataset
ml_100k = movielens.load_feedback()

# Instantiate an evaluation method.
ratio_split = RatioSplit(
    data=ml_100k, test_size=0.2, rating_threshold=4.0, exclude_unknowns=False
)

# Instantiate a PMF recommender model.
pmf = PMF(k=10, max_iter=100, learning_rate=0.001, lambda_reg=0.001)

# Instantiate evaluation metrics.
mae = cornac.metrics.MAE()
rmse = cornac.metrics.RMSE()
rec_20 = cornac.metrics.Recall(k=20)
pre_20 = cornac.metrics.Precision(k=20)

# Instantiate and then run an experiment.
cornac.Experiment(
    eval_method=ratio_split,
    models=[pmf],
    metrics=[mae, rmse, rec_20, pre_20],
    user_based=True,
).run()