class QueryReformulation:
def __init__(self, model_path=None, output_path=''):
self.model = None
self.model_name = None
self.model_output = output_path + '/qr_{name}_model_[e{epoch}]_[p{precision}]_' \
+ str(datetime.now().date()) + '.h5'
if model_path:
self.model = load_model(model_path)
self.model.summary()
def build_model(self, model_name, query_dim, terms_dim, output_dim,
word_embedding):
self.model_name = model_name
query_input = Input(shape=(query_dim, ), name='query_input')
terms_input = Input(shape=(terms_dim, ), name='terms_input')
if model_name == 'lstm':
embedding_feature_block = Sequential(layers=[
Embedding(word_embedding.vocabulary_size,
word_embedding.dimensions,
weights=[word_embedding.embedding_matrix],
trainable=True,
mask_zero=False),
BatchNormalization(),
LSTM(64, return_sequences=True)
])
elif model_name == 'bilstm':
embedding_feature_block = Sequential(layers=[
Embedding(word_embedding.vocabulary_size,
word_embedding.dimensions,
weights=[word_embedding.embedding_matrix],
trainable=True,
mask_zero=False),
BatchNormalization(),
Bidirectional(LSTM(64, return_sequences=True))
])
else: # default cnn
embedding_feature_block = Sequential(layers=[
Embedding(word_embedding.vocabulary_size,
word_embedding.dimensions,
weights=[word_embedding.embedding_matrix],
trainable=True,
mask_zero=False),
BatchNormalization(),
Conv1D(filters=64, kernel_size=3, strides=1),
MaxPooling1D(pool_size=3)
])
# Features
query_feature = embedding_feature_block(query_input)
terms_feature = embedding_feature_block(terms_input)
# Query-Terms alignment
attention = Dot(axes=-1)([query_feature, terms_feature])
softmax_attention = Lambda(lambda x: softmax(x, axis=1),
output_shape=unchanged_shape)(attention)
terms_aligned = Dot(axes=1)([softmax_attention, terms_feature])
# Aligned features
if model_name == 'lstm':
flatten_layer = LSTM(128, return_sequences=False)(terms_aligned)
elif model_name == 'bilstm':
flatten_layer = Bidirectional(LSTM(
128, return_sequences=False))(terms_aligned)
else: # default cnn
merged_cnn = Conv1D(filters=128, kernel_size=3,
strides=1)(terms_aligned)
merged_cnn = MaxPooling1D(pool_size=3)(merged_cnn)
flatten_layer = Flatten()(merged_cnn)
# Output
dense = BatchNormalization()(flatten_layer)
dense = Dense(64, activation='sigmoid')(dense)
out = Dense(output_dim, activation='linear')(dense)
self.model = Model(inputs=[query_input, terms_input], outputs=out)
self.model.compile(optimizer='adam', loss=losses.mean_squared_error)
self.model.summary()
def train_model(self,
query_objs,
query_sequence,
terms_sequence,
candidate_terms,
epochs=20,
batch_size=4):
best_precision = 0
pool = Pool(batch_size)
for e in range(epochs):
print('Epochs: %3d/%d' % (e + 1, epochs))
reward = np.zeros(shape=(len(query_objs)))
precision = np.zeros(shape=(len(query_objs)))
for i, query, q_seq, t_seq, terms in get_batch_data(
query_objs, query_sequence, terms_sequence,
candidate_terms, batch_size):
print(' [%4d-%-4d/%d]' % (i, i + batch_size, len(query_objs)))
weights = self.model.predict(x=[q_seq, t_seq])
batch_reward_precision = pool.map(evaluate_reward_precision,
zip(weights, terms, query))
batch_reward_precision = np.array(batch_reward_precision)
batch_reward = 0.8 * np.asarray(
batch_reward_precision[:,
0]) + 0.2 * reward[i:i + batch_size]
self.model.train_on_batch(x=[q_seq, t_seq],
y=weights,
sample_weight=batch_reward)
reward[i:i + batch_size] = batch_reward_precision[:, 0]
precision[i:i + batch_size] = batch_reward_precision[:, 1]
# Save model
avg_precision = precision.mean()
print(' Average precision %.5f on epoch %d, best precision %.5f' %
(avg_precision, e + 1, best_precision))
if avg_precision > best_precision:
best_precision = avg_precision
self.model.save(filepath=self.model_output.format(
name=self.model_name,
epoch=e + 1,
precision=round(avg_precision, 4)))
pool.close()
pool.join()
def test_model(self,
query_objs,
query_sequence,
terms_sequence,
candidate_terms,
batch_size=4):
pool = Pool(batch_size)
precision_recall = np.zeros(shape=(len(query_objs), 2))
for i, query, q_seq, t_seq, terms in get_batch_data(
query_objs, query_sequence, terms_sequence, candidate_terms,
batch_size):
print('[%4d-%-4d/%d]' % (i, i + batch_size, len(query_objs)))
weights = self.model.predict(x=[q_seq, t_seq])
batch_precision_recall = pool.map(evaluate_precision_recall,
zip(weights, terms, query))
precision_recall[i:i +
batch_size] = np.array(batch_precision_recall)
pool.close()
pool.join()
return precision_recall.mean(axis=0)
def reformulate_query(self,
query_sequence,
terms_sequence,
candidate_terms,
threshold=0.5):
weights = self.model.predict(x=[[query_sequence], [terms_sequence]])
reformulated_query = recreate_query(terms=candidate_terms,
weights=weights[0],
threshold=threshold)
return reformulated_query
def construct_keras_api_model(embedding_weights):
# input_no_time_no_repeat = Input(shape=max_len, dtype='int32')
# embedded_no_time_no_repeat = Embedding(
# creative_id_window,embedding_size,weights=[embedding_weights],trainable=False
# )(input_no_time_no_repeat)
# ==================================================================================
Input_fix_creative_id = Input(shape=(math.ceil(time_id_max / period_days) *
period_length),
dtype='int32',
name='input_fix_creative_id')
Embedded_fix_creative_id = Embedding(
creative_id_window,
embedding_size,
weights=[embedding_weights],
trainable=False)(Input_fix_creative_id)
# ==================================================================================
# input_no_time_with_repeat = Input(shape=max_len, dtype='int32')
# embedded_no_time_with_repeat = Embedding(creative_id_window,embedding_size,weights=[embedding_weights],trainable=False)(input_no_time_with_repeat)
# ----------------------------------------------------------------------
GM_x = keras.layers.GlobalMaxPooling1D()(Embedded_fix_creative_id)
GM_x = Dropout(0.5)(GM_x)
GM_x = Dense(embedding_size // 2, kernel_regularizer=l2(0.001))(GM_x)
GM_x = BatchNormalization()(GM_x)
GM_x = Activation('relu')(GM_x)
GM_x = Dropout(0.5)(GM_x)
GM_x = Dense(embedding_size // 4, kernel_regularizer=l2(0.001))(GM_x)
GM_x = BatchNormalization()(GM_x)
GM_x = Activation('relu')(GM_x)
GM_x = Dense(1, 'sigmoid')(GM_x)
# ----------------------------------------------------------------------
GA_x = GlobalAveragePooling1D()(Embedded_fix_creative_id)
GA_x = Dropout(0.5)(GA_x)
GA_x = Dense(embedding_size // 2, kernel_regularizer=l2(0.001))(GA_x)
GA_x = BatchNormalization()(GA_x)
GA_x = Activation('relu')(GA_x)
GA_x = Dropout(0.5)(GA_x)
GA_x = Dense(embedding_size // 4, kernel_regularizer=l2(0.001))(GA_x)
GA_x = BatchNormalization()(GA_x)
GA_x = Activation('relu')(GA_x)
GA_x = Dense(1, 'sigmoid')(GA_x)
# ==================================================================================
Conv_creative_id = Conv1D(embedding_size, 15, 5,
activation='relu')(Embedded_fix_creative_id)
# ----------------------------------------------------------------------
Conv_GM_x = MaxPooling1D(7)(Conv_creative_id)
Conv_GM_x = Conv1D(embedding_size, 2, 1, activation='relu')(Conv_GM_x)
Conv_GM_x = GlobalMaxPooling1D()(Conv_GM_x)
Conv_GM_x = Dropout(0.5)(Conv_GM_x)
Conv_GM_x = Dense(embedding_size // 2,
kernel_regularizer=l2(0.001))(Conv_GM_x)
Conv_GM_x = BatchNormalization()(Conv_GM_x)
Conv_GM_x = Activation('relu')(Conv_GM_x)
Conv_GM_x = Dropout(0.5)(Conv_GM_x)
Conv_GM_x = Dense(embedding_size // 4,
kernel_regularizer=l2(0.001))(Conv_GM_x)
Conv_GM_x = BatchNormalization()(Conv_GM_x)
Conv_GM_x = Activation('relu')(Conv_GM_x)
Conv_GM_x = Dense(1, 'sigmoid')(Conv_GM_x)
# ----------------------------------------------------------------------
Conv_GA_x = AveragePooling1D(7)(Conv_creative_id)
Conv_GA_x = Conv1D(embedding_size, 2, 1, activation='relu')(Conv_GA_x)
Conv_GA_x = GlobalAveragePooling1D()(Conv_GA_x)
Conv_GA_x = Dropout(0.5)(Conv_GA_x)
Conv_GA_x = Dense(embedding_size // 2,
kernel_regularizer=l2(0.001))(Conv_GA_x)
Conv_GA_x = BatchNormalization()(Conv_GA_x)
Conv_GA_x = Activation('relu')(Conv_GA_x)
Conv_GA_x = Dropout(0.5)(Conv_GA_x)
Conv_GA_x = Dense(embedding_size // 4,
kernel_regularizer=l2(0.001))(Conv_GA_x)
Conv_GA_x = BatchNormalization()(Conv_GA_x)
Conv_GA_x = Activation('relu')(Conv_GA_x)
Conv_GA_x = Dense(1, 'sigmoid')(Conv_GA_x)
# ----------------------------------------------------------------------
LSTM_x = Conv1D(embedding_size, 14, 7, activation='relu')(Conv_creative_id)
LSTM_x = LSTM(embedding_size, return_sequences=True)(LSTM_x)
LSTM_x = LSTM(embedding_size, return_sequences=True)(LSTM_x)
LSTM_x = LSTM(embedding_size)(LSTM_x)
LSTM_x = Dropout(0.5)(LSTM_x)
LSTM_x = Dense(embedding_size // 2, kernel_regularizer=l2(0.001))(LSTM_x)
LSTM_x = BatchNormalization()(LSTM_x)
LSTM_x = Activation('relu')(LSTM_x)
LSTM_x = Dropout(0.5)(LSTM_x)
LSTM_x = Dense(embedding_size // 4, kernel_regularizer=l2(0.001))(LSTM_x)
LSTM_x = BatchNormalization()(LSTM_x)
LSTM_x = Activation('relu')(LSTM_x)
LSTM_x = Dense(1, 'sigmoid')(LSTM_x)
# ----------------------------------------------------------------------
concatenated = concatenate([
GM_x,
GA_x,
Conv_GM_x,
Conv_GA_x,
LSTM_x,
],
axis=-1)
output_tensor = Dense(1, 'sigmoid')(concatenated)
keras_api_model = Model(
[
# input_no_time_no_repeat,
Input_fix_creative_id,
# input_no_time_with_repeat,
],
output_tensor)
keras_api_model.summary()
plot_model(keras_api_model, to_file='model/keras_api_word2vec_model.png')
print('-' * 5 + ' ' * 3 + "编译模型" + ' ' * 3 + '-' * 5)
keras_api_model.compile(optimizer=optimizers.RMSprop(lr=RMSProp_lr),
loss=losses.binary_crossentropy,
metrics=[metrics.binary_accuracy])
return keras_api_model