def test_movielens_accuracy_sample_weights_grad_accumulation():
# Set weights to zero for all even-numbered users
# and check that they have not accumulated any
# gradient updates.
weights = train.copy()
weights.data = np.ones(train.getnnz(),
dtype=np.float32)
even_users = weights.row % 2 == 0
weights.data *= even_users
even_idx = np.arange(train.shape[0]) % 2 == 0
odd_idx = np.arange(train.shape[0]) % 2 != 0
for loss in ('logistic', 'bpr', 'warp'):
model = LightFM(loss=loss, random_state=SEED)
model.fit_partial(train,
sample_weight=weights,
epochs=1)
assert np.allclose(model.user_embedding_gradients[odd_idx], 1.0)
assert np.allclose(model.user_bias_gradients[odd_idx], 1.0)
assert not np.allclose(model.user_embedding_gradients[even_idx], 1.0)
assert not np.allclose(model.user_bias_gradients[even_idx], 1.0)
def test_predict_ranks():
no_users, no_items = (10, 100)
train = sp.coo_matrix((no_users,
no_items),
dtype=np.float32)
model = LightFM()
model.fit_partial(train)
# Compute ranks for all items
rank_input = sp.csr_matrix(np.ones((no_users, no_items)))
ranks = model.predict_rank(rank_input, num_threads=2).todense()
assert np.all(ranks.min(axis=1) == 0)
assert np.all(ranks.max(axis=1) == no_items - 1)
for row in range(no_users):
assert np.all(np.sort(ranks[row]) == np.arange(no_items))
# Make sure this is true also when there are ties
model.user_embeddings = np.zeros_like(model.user_embeddings)
model.item_embeddings = np.zeros_like(model.item_embeddings)
model.user_biases = np.zeros_like(model.user_biases)
model.item_biases = np.zeros_like(model.item_biases)
ranks = model.predict_rank(rank_input, num_threads=2).todense()
assert np.all(ranks.min(axis=1) == 0)
assert np.all(ranks.max(axis=1) == 0)
# Wrong input dimensions
with pytest.raises(ValueError):
model.predict_rank(sp.csr_matrix((5, 5)), num_threads=2)
def test_warp_kos_precision():
# Remove all negative examples
training = train.copy()
training.data[training.data < 1] = 0
training = training.tocsr()
training.eliminate_zeros()
model = LightFM(learning_rate=0.05, k=5,
loss='warp-kos')
model.fit_partial(training,
epochs=10)
train_precision = precision_at_k(model,
training,
10)
test_precision = precision_at_k(model,
test,
10)
full_train_auc = full_auc(model, training)
full_test_auc = full_auc(model, test)
assert train_precision > 0.44
assert test_precision > 0.06
assert full_train_auc > 0.9
assert full_test_auc > 0.87
def test_input_dtypes():
dtypes = (np.int32,
np.int64,
np.float32,
np.float64)
no_users, no_items = (10, 100)
no_features = 20
for dtype in dtypes:
train = sp.coo_matrix((no_users,
no_items),
dtype=dtype)
user_features = sp.coo_matrix((no_users,
no_features),
dtype=dtype)
item_features = sp.coo_matrix((no_items,
no_features),
dtype=dtype)
model = LightFM()
model.fit_partial(train,
user_features=user_features,
item_features=item_features)
model.predict(np.random.randint(0, no_users, 10).astype(np.int32),
np.random.randint(0, no_items, 10).astype(np.int32),
user_features=user_features,
item_features=item_features)
def test_warp_kos_precision():
# Remove all negative examples
training = train.copy()
training.data[training.data < 1] = 0
training = training.tocsr()
training.eliminate_zeros()
model = LightFM(learning_rate=0.05, k=5,
loss='warp-kos',
random_state=SEED)
model.fit_partial(training,
epochs=10)
(train_precision,
test_precision,
full_train_auc,
full_test_auc) = _get_metrics(model,
train,
test)
assert train_precision > 0.44
assert test_precision > 0.06
assert full_train_auc > 0.9
assert full_test_auc > 0.87
def test_movielens_accuracy_sample_weights():
# Scaling weights down and learning rate up
# by the same amount should result in
# roughly the same accuracy
scale = 1e-01
weights = train.copy()
weights.data = np.ones(train.getnnz(),
dtype=np.float32) * scale
for (loss, exp_score) in (('logistic', 0.74),
('bpr', 0.84),
('warp', 0.89)):
model = LightFM(loss=loss, random_state=SEED)
model.learning_rate * 1.0 / scale
model.fit_partial(train,
sample_weight=weights,
epochs=10)
(train_precision,
test_precision,
full_train_auc,
full_test_auc) = _get_metrics(model,
train,
test)
assert full_train_auc > exp_score
def test_feature_inference_fails():
# On predict if we try to use feature inference and supply
# higher ids than the number of features that were supplied to fit
# we should complain
no_users, no_items = (10, 100)
no_features = 20
train = sp.coo_matrix((no_users,
no_items),
dtype=np.int32)
user_features = sp.csr_matrix((no_users,
no_features),
dtype=np.int32)
item_features = sp.csr_matrix((no_items,
no_features),
dtype=np.int32)
model = LightFM()
model.fit_partial(train,
user_features=user_features,
item_features=item_features)
with pytest.raises(AssertionError):
model.predict(np.array([no_features], dtype=np.int32),
np.array([no_features], dtype=np.int32))
def test_auc_score():
no_users, no_items = (10, 100)
train, test = _generate_data(no_users, no_items)
model = LightFM(loss='bpr')
model.fit_partial(train)
auc = evaluation.auc_score(model,
test,
num_threads=2)
expected_auc = np.array(_auc(model,
test))
assert auc.shape == expected_auc.shape
assert np.abs(auc.mean() - expected_auc.mean()) < 0.01
assert len(auc) == (test.getnnz(axis=1) > 0).sum()
assert len(evaluation.auc_score(model,
train,
preserve_rows=True)) == test.shape[0]
# With omitting train interactions
auc = evaluation.auc_score(model,
test,
train_interactions=train,
num_threads=2)
expected_auc = np.array(_auc(model,
test,
train))
assert np.abs(auc.mean() - expected_auc.mean()) < 0.01
def test_matrix_types():
mattypes = (sp.coo_matrix, sp.lil_matrix, sp.csr_matrix, sp.csc_matrix)
dtypes = (np.int32, np.int64, np.float32, np.float64)
no_users, no_items = (10, 100)
no_features = 20
for mattype in mattypes:
for dtype in dtypes:
train = mattype((no_users, no_items), dtype=dtype)
user_features = mattype((no_users, no_features), dtype=dtype)
item_features = mattype((no_items, no_features), dtype=dtype)
model = LightFM()
model.fit_partial(train, user_features=user_features, item_features=item_features)
model.predict(
np.random.randint(0, no_users, 10).astype(np.int32),
np.random.randint(0, no_items, 10).astype(np.int32),
user_features=user_features,
item_features=item_features,
)
def test_warp_precision_adadelta_multithreaded():
model = LightFM(learning_schedule='adadelta',
rho=0.95,
epsilon=0.000001,
loss='warp')
model.fit_partial(train,
epochs=10,
num_threads=4)
train_precision = precision_at_k(model,
train,
10)
test_precision = precision_at_k(model,
test,
10)
full_train_auc = full_auc(model, train)
full_test_auc = full_auc(model, test)
assert train_precision > 0.45
assert test_precision > 0.07
assert full_train_auc > 0.94
assert full_test_auc > 0.9
def test_predict(num_threads=2):
no_users, no_items = (10, 100)
train = sp.coo_matrix((no_users,
no_items),
dtype=np.int32)
model = LightFM()
model.fit_partial(train)
for uid in range(no_users):
scores_arr = model.predict(np.repeat(uid, no_items),
np.arange(no_items))
scores_int = model.predict(uid,
np.arange(no_items))
assert np.allclose(scores_arr, scores_int)
scores_parallel = model.predict(np.repeat(uid, no_items),
np.arange(no_items),
num_threads=num_threads)
assert np.allclose(scores_parallel, scores_arr)
scores_no_prec = model.predict(np.repeat(uid, no_items),
np.arange(no_items),
num_threads=num_threads,
precompute_representations=False)
assert np.allclose(scores_parallel, scores_no_prec)
scores_no_prec_serial = model.predict(np.repeat(uid, no_items),
np.arange(no_items),
num_threads=1,
precompute_representations=False)
assert np.allclose(scores_parallel, scores_no_prec_serial)
def test_empty_matrix():
no_users, no_items = (10, 100)
train = sp.coo_matrix((no_users, no_items), dtype=np.int32)
model = LightFM()
model.fit_partial(train)
def fit_lightfm_model():
""" Fit the lightFM model
returns d_user_pred, list_user, list_coupon
list_coupon = list of test coupons
list_user = list of user ID
d_user_pred : key = user, value = predicted ranking of coupons in list_coupon
"""
#Load data
Mui_train = spi.mmread("../Data/Data_translated/biclass_user_item_train_mtrx.mtx")
uf = spi.mmread("../Data/Data_translated/user_feat_mtrx.mtx")
itrf = spi.mmread("../Data/Data_translated/train_item_feat_mtrx.mtx")
itef = spi.mmread("../Data/Data_translated/test_item_feat_mtrx.mtx")
#Print shapes as a check
print "user_features shape: %s,\nitem train features shape: %s,\nitem test features shape: %s" % (uf.shape, itrf.shape, itef.shape)
#Load test coupon and user lists
cplte = pd.read_csv("../Data/Data_translated/coupon_list_test_translated.csv")
ulist = pd.read_csv("../Data/Data_translated/user_list_translated.csv")
list_coupon = cplte["COUPON_ID_hash"].values
list_user = ulist["USER_ID_hash"].values
#Build model
no_comp, lr, ep = 10, 0.01, 5
model = LightFM(no_components=no_comp, learning_rate=lr, loss='warp')
model.fit_partial(Mui_train, user_features = uf, item_features = itrf, epochs = ep, num_threads = 4, verbose = True)
test = sps.csr_matrix((len(list_user), len(list_coupon)), dtype = np.int32)
no_users, no_items = test.shape
pid_array = np.arange(no_items, dtype=np.int32)
#Create and initialise dict to store predictions
d_user_pred = {}
for user in list_user :
d_user_pred[user] = []
# Loop over users and compute predictions
for user_id, row in enumerate(test):
sys.stdout.write("\rProcessing user " + str(user_id)+"/ "+str(len(list_user)))
sys.stdout.flush()
uid_array = np.empty(no_items, dtype=np.int32)
uid_array.fill(user_id)
predictions = model.predict(uid_array, pid_array,user_features = uf, item_features = itef, num_threads=4)
user = str(list_user[user_id])
# apply MinMaxScaler for blending later on
MMS = MinMaxScaler()
pred = MMS.fit_transform(np.ravel(predictions))
d_user_pred[user] = pred
# Pickle the predictions for future_use
d_pred = {"list_coupon" : list_coupon.tolist(), "d_user_pred" : d_user_pred}
with open("../Data/Data_translated/d_pred_lightfm.pickle", "w") as f:
pickle.dump(d_pred, f, protocol = pickle.HIGHEST_PROTOCOL)
return d_user_pred, list_user, list_coupon
def test_random_state_fixing():
model = LightFM(learning_rate=0.05, loss='warp', random_state=SEED)
model.fit_partial(train, epochs=2)
model_2 = LightFM(learning_rate=0.05, loss='warp', random_state=SEED)
model_2.fit_partial(train, epochs=2)
assert np.all(model.user_embeddings == model_2.user_embeddings)
assert np.all(model.item_embeddings == model_2.item_embeddings)
def test_movielens_accuracy_resume():
model = LightFM(random_state=SEED)
for _ in range(10):
model.fit_partial(train, epochs=1)
train_predictions = model.predict(train.row, train.col)
test_predictions = model.predict(test.row, test.col)
assert roc_auc_score(train.data, train_predictions) > 0.84
assert roc_auc_score(test.data, test_predictions) > 0.76
def test_not_enough_features_fails():
no_users, no_items = (10, 100)
no_features = 20
train = sp.coo_matrix((no_users, no_items), dtype=np.int32)
user_features = sp.csr_matrix((no_users - 1, no_features), dtype=np.int32)
item_features = sp.csr_matrix((no_items - 1, no_features), dtype=np.int32)
model = LightFM()
with pytest.raises(Exception):
model.fit_partial(train, user_features=user_features, item_features=item_features)
def test_predict():
no_users, no_items = (10, 100)
train = sp.coo_matrix((no_users, no_items), dtype=np.int32)
model = LightFM()
model.fit_partial(train)
for uid in range(no_users):
scores_arr = model.predict(np.repeat(uid, no_items), np.arange(no_items))
scores_int = model.predict(uid, np.arange(no_items))
assert np.allclose(scores_arr, scores_int)
def test_warp_stability():
learning_rates = (0.05, 0.1, 0.5)
for lrate in learning_rates:
model = LightFM(learning_rate=lrate,
loss='warp')
model.fit_partial(train,
epochs=10)
assert not np.isnan(model.user_embeddings).any()
assert not np.isnan(model.item_embeddings).any()
def test_movielens_accuracy():
model = LightFM()
model.fit_partial(train,
epochs=10)
train_predictions = model.predict(train.row,
train.col)
test_predictions = model.predict(test.row,
test.col)
assert roc_auc_score(train.data, train_predictions) > 0.84
assert roc_auc_score(test.data, test_predictions) > 0.76
def test_overfitting():
# Let's massivly overfit
model = LightFM(no_components=50, random_state=SEED)
model.fit_partial(train, epochs=30)
train_predictions = model.predict(train.row, train.col)
test_predictions = model.predict(test.row, test.col)
overfit_train = roc_auc_score(train.data, train_predictions)
overfit_test = roc_auc_score(test.data, test_predictions)
assert overfit_train > 0.99
assert overfit_test < 0.75
def test_logistic_precision():
model = LightFM(random_state=SEED)
model.fit_partial(train, epochs=10)
(train_precision, test_precision, full_train_auc,
full_test_auc) = _get_metrics(model, train, test)
assert train_precision > 0.3
assert test_precision > 0.03
assert full_train_auc > 0.79
assert full_test_auc > 0.73
def test_zeros_negative_accuracy():
# Should get the same accuracy when zeros are used to
# denote negative interactions
train.data[train.data == -1] = 0
model = LightFM(random_state=SEED)
model.fit_partial(train, epochs=10)
train_predictions = model.predict(train.row, train.col)
test_predictions = model.predict(test.row, test.col)
assert roc_auc_score(train.data, train_predictions) > 0.84
assert roc_auc_score(test.data, test_predictions) > 0.76
def test_predict_ranks():
no_users, no_items = (10, 100)
train = sp.coo_matrix((no_users,
no_items),
dtype=np.float32)
train = sp.rand(no_users, no_items, format='csr', random_state=42)
model = LightFM()
model.fit_partial(train)
# Compute ranks for all items
rank_input = sp.csr_matrix(np.ones((no_users, no_items)))
ranks = model.predict_rank(rank_input, num_threads=2).todense()
assert np.all(ranks.min(axis=1) == 0)
assert np.all(ranks.max(axis=1) == no_items - 1)
for row in range(no_users):
assert np.all(np.sort(ranks[row]) == np.arange(no_items))
# Train set exclusions. All ranks should be zero
# if train interactions is dense.
ranks = model.predict_rank(rank_input,
train_interactions=rank_input).todense()
assert np.all(ranks == 0)
# Max rank should be num_items - 1 - number of positives
# in train in that row
ranks = model.predict_rank(rank_input,
train_interactions=train).todense()
assert np.all(np.squeeze(np.array(ranks.max(axis=1))) ==
no_items - 1 - np.squeeze(np.array(train.getnnz(axis=1))))
# Make sure ranks are computed pessimistically when
# there are ties (that is, equal predictions for every
# item will assign maximum rank to each).
model.user_embeddings = np.zeros_like(model.user_embeddings)
model.item_embeddings = np.zeros_like(model.item_embeddings)
model.user_biases = np.zeros_like(model.user_biases)
model.item_biases = np.zeros_like(model.item_biases)
ranks = model.predict_rank(rank_input, num_threads=2).todense()
assert np.all(ranks.min(axis=1) == 99)
assert np.all(ranks.max(axis=1) == 99)
# Wrong input dimensions
with pytest.raises(ValueError):
model.predict_rank(sp.csr_matrix((5, 5)), num_threads=2)
def test_movielens_excessive_regularization():
# Should perform poorly with high regularization
model = LightFM(no_components=10,
item_alpha=1.0,
user_alpha=1.0,
random_state=SEED)
model.fit_partial(train, epochs=10)
train_predictions = model.predict(train.row, train.col)
test_predictions = model.predict(test.row, test.col)
assert roc_auc_score(train.data, train_predictions) < 0.6
assert roc_auc_score(test.data, test_predictions) < 0.6
def test_predict():
no_users, no_items = (10, 100)
train = sp.coo_matrix((no_users, no_items), dtype=np.int32)
model = LightFM()
model.fit_partial(train)
for uid in range(no_users):
scores_arr = model.predict(np.repeat(uid, no_items),
np.arange(no_items))
scores_int = model.predict(uid, np.arange(no_items))
assert np.allclose(scores_arr, scores_int)
def test_regularization():
# Let's regularize
model = LightFM(no_components=50,
item_alpha=0.0001,
user_alpha=0.0001,
random_state=SEED)
model.fit_partial(train, epochs=30)
train_predictions = model.predict(train.row, train.col)
test_predictions = model.predict(test.row, test.col)
assert roc_auc_score(train.data, train_predictions) > 0.80
assert roc_auc_score(test.data, test_predictions) > 0.75
def test_warp_precision_multithreaded():
model = LightFM(learning_rate=0.05, loss='warp', random_state=SEED)
model.fit_partial(train, epochs=10, num_threads=4)
(train_precision, test_precision, full_train_auc,
full_test_auc) = _get_metrics(model, train, test)
assert train_precision > 0.45
assert test_precision > 0.07
assert full_train_auc > 0.94
assert full_test_auc > 0.9
def test_not_enough_features_fails():
no_users, no_items = (10, 100)
no_features = 20
train = sp.coo_matrix((no_users, no_items), dtype=np.int32)
user_features = sp.csr_matrix((no_users - 1, no_features), dtype=np.int32)
item_features = sp.csr_matrix((no_items - 1, no_features), dtype=np.int32)
model = LightFM()
with pytest.raises(Exception):
model.fit_partial(train,
user_features=user_features,
item_features=item_features)
def test_bpr_precision():
model = LightFM(learning_rate=0.05, loss='bpr', random_state=SEED)
model.fit_partial(train, epochs=10)
(train_precision, test_precision, full_train_auc,
full_test_auc) = _get_metrics(model, train, test)
assert train_precision > 0.31
assert test_precision > 0.04
assert full_train_auc > 0.86
assert full_test_auc > 0.84
def test_random_state_advanced():
# Check that using the random state
# to seed rand_r in Cython advances
# the random generator state.
model = LightFM(learning_rate=0.05, loss='warp', random_state=SEED)
model.fit_partial(train, epochs=1)
rng_state = model.rng.get_state()[1].copy()
model.fit_partial(train, epochs=1)
assert not np.all(rng_state == model.rng.get_state()[1])
def test_predict_ranks():
no_users, no_items = (10, 100)
train = sp.coo_matrix((no_users,
no_items),
dtype=np.float32)
train = sp.rand(no_users, no_items, format='csr')
model = LightFM()
model.fit_partial(train)
# Compute ranks for all items
rank_input = sp.csr_matrix(np.ones((no_users, no_items)))
ranks = model.predict_rank(rank_input, num_threads=2).todense()
assert np.all(ranks.min(axis=1) == 0)
assert np.all(ranks.max(axis=1) == no_items - 1)
for row in range(no_users):
assert np.all(np.sort(ranks[row]) == np.arange(no_items))
# Train set exclusions. All ranks should be zero
# if train interactions is dense.
ranks = model.predict_rank(rank_input,
train_interactions=rank_input).todense()
assert np.all(ranks == 0)
# Max rank should be num_items - 1 - number of positives
# in train in that row
ranks = model.predict_rank(rank_input,
train_interactions=train).todense()
assert np.all(np.squeeze(np.array(ranks.max(axis=1))) ==
no_items - 1 - np.squeeze(np.array(train.getnnz(axis=1))))
# Make sure invariants hold when there are ties
model.user_embeddings = np.zeros_like(model.user_embeddings)
model.item_embeddings = np.zeros_like(model.item_embeddings)
model.user_biases = np.zeros_like(model.user_biases)
model.item_biases = np.zeros_like(model.item_biases)
ranks = model.predict_rank(rank_input, num_threads=2).todense()
assert np.all(ranks.min(axis=1) == 0)
assert np.all(ranks.max(axis=1) == 0)
# Wrong input dimensions
with pytest.raises(ValueError):
model.predict_rank(sp.csr_matrix((5, 5)), num_threads=2)
def test_training_schedules():
model = LightFM(no_components=10,
learning_schedule='adagrad',
random_state=SEED)
model.fit_partial(train,
epochs=0)
assert (model.item_embedding_gradients == 1).all()
assert (model.item_embedding_momentum == 0).all()
assert (model.item_bias_gradients == 1).all()
assert (model.item_bias_momentum == 0).all()
assert (model.user_embedding_gradients == 1).all()
assert (model.user_embedding_momentum == 0).all()
assert (model.user_bias_gradients == 1).all()
assert (model.user_bias_momentum == 0).all()
model.fit_partial(train,
epochs=1)
assert (model.item_embedding_gradients > 1).any()
assert (model.item_embedding_momentum == 0).all()
assert (model.item_bias_gradients > 1).any()
assert (model.item_bias_momentum == 0).all()
assert (model.user_embedding_gradients > 1).any()
assert (model.user_embedding_momentum == 0).all()
assert (model.user_bias_gradients > 1).any()
assert (model.user_bias_momentum == 0).all()
model = LightFM(no_components=10,
learning_schedule='adadelta',
random_state=SEED)
model.fit_partial(train,
epochs=0)
assert (model.item_embedding_gradients == 0).all()
assert (model.item_embedding_momentum == 0).all()
assert (model.item_bias_gradients == 0).all()
assert (model.item_bias_momentum == 0).all()
assert (model.user_embedding_gradients == 0).all()
assert (model.user_embedding_momentum == 0).all()
assert (model.user_bias_gradients == 0).all()
assert (model.user_bias_momentum == 0).all()
model.fit_partial(train,
epochs=1)
assert (model.item_embedding_gradients > 0).any()
assert (model.item_embedding_momentum > 0).any()
assert (model.item_bias_gradients > 0).any()
assert (model.item_bias_momentum > 0).any()
assert (model.user_embedding_gradients > 0).any()
assert (model.user_embedding_momentum > 0).any()
assert (model.user_bias_gradients > 0).any()
assert (model.user_bias_momentum > 0).any()
def test_movielens_accuracy_resume():
model = LightFM(random_state=SEED)
for _ in range(10):
model.fit_partial(train,
epochs=1)
train_predictions = model.predict(train.row,
train.col)
test_predictions = model.predict(test.row,
test.col)
assert roc_auc_score(train.data, train_predictions) > 0.84
assert roc_auc_score(test.data, test_predictions) > 0.76
def test_warp_precision_max_sampled():
model = LightFM(learning_rate=0.05, max_sampled=1, loss='warp')
# This is equivalent to a no-op pass
# over the training data
model.max_sampled = 0
model.fit_partial(train, epochs=1)
full_train_auc = full_auc(model, train)
full_test_auc = full_auc(model, test)
# The AUC should be no better than random
assert full_train_auc < 0.55
assert full_test_auc < 0.55
def test_regularization():
# Let's regularize
model = LightFM(no_components=50,
item_alpha=0.0001,
user_alpha=0.0001)
model.fit_partial(train,
epochs=30)
train_predictions = model.predict(train.row,
train.col)
test_predictions = model.predict(test.row,
test.col)
assert roc_auc_score(train.data, train_predictions) > 0.80
assert roc_auc_score(test.data, test_predictions) > 0.75
def test_overfitting():
# Let's massivly overfit
model = LightFM(no_components=50)
model.fit_partial(train,
epochs=30)
train_predictions = model.predict(train.row,
train.col)
test_predictions = model.predict(test.row,
test.col)
overfit_train = roc_auc_score(train.data, train_predictions)
overfit_test = roc_auc_score(test.data, test_predictions)
assert overfit_train > 0.99
assert overfit_test < 0.75
def test_auc_score():
no_users, no_items = (10, 100)
train = sp.rand(no_users, no_items, format='coo')
train.data = np.ones_like(train.data)
model = LightFM(loss='bpr')
model.fit_partial(train)
auc = evaluation.auc_score(model, train,
num_threads=2)[train.getnnz(axis=1) > 0]
expected_auc = np.array(_auc(model, train))
assert auc.shape == expected_auc.shape
assert np.abs(auc.mean() - expected_auc.mean()) < 0.01
def test_zeros_negative_accuracy():
# Should get the same accuracy when zeros are used to
# denote negative interactions
train.data[train.data == -1] = 0
model = LightFM()
model.fit_partial(train,
epochs=10)
train_predictions = model.predict(train.row,
train.col)
test_predictions = model.predict(test.row,
test.col)
assert roc_auc_score(train.data, train_predictions) > 0.84
assert roc_auc_score(test.data, test_predictions) > 0.76
def test_logistic_precision():
model = LightFM()
model.fit_partial(train, epochs=10)
train_precision = precision_at_k(model, train, 10)
test_precision = precision_at_k(model, test, 10)
full_train_auc = full_auc(model, train)
full_test_auc = full_auc(model, test)
assert train_precision > 0.3
assert test_precision > 0.03
assert full_train_auc > 0.79
assert full_test_auc > 0.74
def test_movielens_excessive_regularization():
# Should perform poorly with high regularization
model = LightFM(no_components=10,
item_alpha=1.0,
user_alpha=1.0)
model.fit_partial(train,
epochs=10)
train_predictions = model.predict(train.row,
train.col)
test_predictions = model.predict(test.row,
test.col)
assert roc_auc_score(train.data, train_predictions) < 0.6
assert roc_auc_score(test.data, test_predictions) < 0.6
def test_warp_precision():
model = LightFM(learning_rate=0.05, loss='warp')
model.fit_partial(train, epochs=10)
train_precision = precision_at_k(model, train, 10)
test_precision = precision_at_k(model, test, 10)
full_train_auc = full_auc(model, train)
full_test_auc = full_auc(model, test)
assert train_precision > 0.45
assert test_precision > 0.07
assert full_train_auc > 0.94
assert full_test_auc > 0.9
def test_bpr_precision_high_interaction_values():
model = LightFM(learning_rate=0.05, loss='bpr', random_state=SEED)
_train = train.copy()
_train.data = _train.data * 5
model.fit_partial(_train, epochs=10)
(train_precision, test_precision, full_train_auc,
full_test_auc) = _get_metrics(model, _train, test)
assert train_precision > 0.31
assert test_precision > 0.04
assert full_train_auc > 0.86
assert full_test_auc > 0.84
def test_precision_at_k():
no_users, no_items = (10, 100)
train = sp.rand(no_users, no_items, format='coo')
train.data = np.ones_like(train.data)
model = LightFM(loss='bpr')
model.fit_partial(train)
k = 10
mean_precision = evaluation.precision_at_k(
model, train, k=k)[train.getnnz(axis=1) > 0].mean()
expected_mean_precision = _precision_at_k(model, train, k)
assert np.allclose(mean_precision, expected_mean_precision)
def test_zero_weights_accuracy():
# When very small weights are used
# accuracy should be no better than
# random.
weights = train.copy()
weights.data = np.zeros(train.getnnz(), dtype=np.float32)
for loss in ('logistic', 'bpr', 'warp'):
model = LightFM(loss=loss, random_state=SEED)
model.fit_partial(train, sample_weight=weights, epochs=10)
train_predictions = model.predict(train.row, train.col)
test_predictions = model.predict(test.row, test.col)
assert 0.45 < roc_auc_score(train.data, train_predictions) < 0.55
assert 0.45 < roc_auc_score(test.data, test_predictions) < 0.55
def test_hogwild_accuracy():
# Should get comparable accuracy with 2 threads
model = LightFM()
model.fit_partial(train,
epochs=10,
num_threads=2)
train_predictions = model.predict(train.row,
train.col,
num_threads=2)
test_predictions = model.predict(test.row,
test.col,
num_threads=2)
assert roc_auc_score(train.data, train_predictions) > 0.84
assert roc_auc_score(test.data, test_predictions) > 0.76
def test_bpr_precision_multithreaded():
model = LightFM(learning_rate=0.05, loss='bpr')
model.fit_partial(train, epochs=10, num_threads=4)
train_precision = precision_at_k(model, train, 10)
test_precision = precision_at_k(model, test, 10)
full_train_auc = full_auc(model, train)
full_test_auc = full_auc(model, test)
assert train_precision > 0.31
assert test_precision > 0.04
assert full_train_auc > 0.86
assert full_test_auc > 0.84
def test_return_self():
no_users, no_items = (10, 100)
train = sp.coo_matrix((no_users, no_items), dtype=np.int32)
model = LightFM()
assert model.fit_partial(train) is model
assert model.fit(train) is model
def test_warp_precision_adadelta():
model = LightFM(learning_schedule='adadelta',
rho=0.95,
epsilon=0.000001,
loss='warp',
random_state=SEED)
model.fit_partial(train, epochs=10, num_threads=1)
(train_precision, test_precision, full_train_auc,
full_test_auc) = _get_metrics(model, train, test)
assert train_precision > 0.45
assert test_precision > 0.07
assert full_train_auc > 0.94
assert full_test_auc > 0.9
def test_random_state_fixing():
model = LightFM(learning_rate=0.05,
loss='warp',
random_state=SEED)
model.fit_partial(train,
epochs=2)
model_2 = LightFM(learning_rate=0.05,
loss='warp',
random_state=SEED)
model_2.fit_partial(train,
epochs=2)
assert np.all(model.user_embeddings == model_2.user_embeddings)
assert np.all(model.item_embeddings == model_2.item_embeddings)
def test_random_state_advanced():
# Check that using the random state
# to seed rand_r in Cython advances
# the random generator state.
model = LightFM(learning_rate=0.05,
loss='warp',
random_state=SEED)
model.fit_partial(train,
epochs=1)
rng_state = model.random_state.get_state()[1].copy()
model.fit_partial(train,
epochs=1)
assert not np.all(rng_state == model.random_state.get_state()[1])
def test_auc_score():
no_users, no_items = (10, 100)
train = sp.rand(no_users, no_items, format='coo')
train.data = np.ones_like(train.data)
model = LightFM(loss='bpr')
model.fit_partial(train)
auc = evaluation.auc_score(model,
train,
num_threads=2)[train.getnnz(axis=1) > 0]
expected_auc = np.array(_auc(model,
train))
assert auc.shape == expected_auc.shape
assert np.abs(auc.mean() - expected_auc.mean()) < 0.01
def test_logistic_precision():
model = LightFM(random_state=SEED)
model.fit_partial(train,
epochs=10)
(train_precision,
test_precision,
full_train_auc,
full_test_auc) = _get_metrics(model,
train,
test)
assert train_precision > 0.3
assert test_precision > 0.03
assert full_train_auc > 0.79
assert full_test_auc > 0.73
def update(self,
mat_interaction,
mat_user_feature,
mat_item_feature,
epoch=3,
threads=8):
model = LightFM(loss=self.loss,
learning_rate=self.learning_rate,
item_alpha=self.item_alpha,
user_alpha=self.user_alpha)
model.fit_partial(mat_interaction,
user_features=mat_user_feature,
item_features=mat_item_feature,
epochs=epoch,
num_threads=threads,
verbose=False)
return model
def test_return_self():
no_users, no_items = (10, 100)
train = sp.coo_matrix((no_users, no_items), dtype=np.int32)
model = LightFM()
assert model.fit_partial(train) is model
assert model.fit(train) is model
class LightFMRecommender(object):
def __init__(self,
n_comp=30,
loss='warp-kos',
learning='adagrad',
alpha=1e-3):
alpha = 1e-3
self.model = LightFM(no_components=30,
loss='warp-kos',
learning_schedule='adagrad',
user_alpha=alpha,
item_alpha=alpha)
# self.model = LightFM(no_components=n_comp,
# loss=loss,
# learning_schedule= learning,
# user_alpha=alpha, item_alpha=alpha)
def fit(self, urm, epochs=100):
self.urm = urm
self.n_tracks = urm.shape[1]
for epoch in range(epochs):
self.model.fit_partial(urm.getCSR(), epochs=1)
def get_pred_row(self, user_id):
return self.model.predict(user_id, np.arange(self.n_tracks))
def s_recommend(self, user_id, nRec=10):
scores = self.model.predict(user_id, np.arange(self.n_tracks))
top_items = np.argsort(-scores)
recommended_items = self._filter_seen(user_id, top_items)
return recommended_items[0:nRec]
def _filter_seen(self, user_id, ranking):
seen = self.urm.extractTracksFromPlaylist(user_id)
unseen_mask = np.in1d(ranking, seen, assume_unique=True, invert=True)
return ranking[unseen_mask]
def m_recommend(self, target_ids, nRec=10):
results = []
for tid in target_ids:
results.append(self.s_recommend(tid, nRec))
return results
def test_user_supplied_features_accuracy():
model = LightFM()
model.fit_partial(train,
user_features=train_user_features,
item_features=train_item_features,
epochs=10)
train_predictions = model.predict(train.row,
train.col,
user_features=train_user_features,
item_features=train_item_features)
test_predictions = model.predict(test.row,
test.col,
user_features=test_user_features,
item_features=test_item_features)
assert roc_auc_score(train.data, train_predictions) > 0.84
assert roc_auc_score(test.data, test_predictions) > 0.76