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#@title 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
#
# https://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.
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#@test {"skip": true}
!pip install tensorflow-lattice pydot
Importing required packages:
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import tensorflow as tf
import collections
import logging
import numpy as np
import pandas as pd
import sys
import tensorflow_lattice as tfl
logging.disable(sys.maxsize)
Downloading the Puzzles dataset:
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train_dataframe = pd.read_csv(
'https://raw.githubusercontent.com/wbakst/puzzles_data/master/train.csv')
train_dataframe.head()
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test_dataframe = pd.read_csv(
'https://raw.githubusercontent.com/wbakst/puzzles_data/master/test.csv')
test_dataframe.head()
Extract and convert features and labels
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# Features:
# - star_rating rating out of 5 stars (1-5)
# - word_count number of words in the review
# - is_amazon 1 = reviewed on amazon; 0 = reviewed on artifact website
# - includes_photo if the review includes a photo of the puzzle
# - num_helpful number of people that found this review helpful
# - num_reviews total number of reviews for this puzzle (we construct)
#
# This ordering of feature names will be the exact same order that we construct
# our model to expect.
feature_names = [
'star_rating', 'word_count', 'is_amazon', 'includes_photo', 'num_helpful',
'num_reviews'
]
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def extract_features(dataframe, label_name):
# First we extract flattened features.
flattened_features = {
feature_name: dataframe[feature_name].values.astype(float)
for feature_name in feature_names[:-1]
}
# Construct mapping from puzzle name to feature.
star_rating = collections.defaultdict(list)
word_count = collections.defaultdict(list)
is_amazon = collections.defaultdict(list)
includes_photo = collections.defaultdict(list)
num_helpful = collections.defaultdict(list)
labels = {}
# Extract each review.
for i in range(len(dataframe)):
row = dataframe.iloc[i]
puzzle_name = row['puzzle_name']
star_rating[puzzle_name].append(float(row['star_rating']))
word_count[puzzle_name].append(float(row['word_count']))
is_amazon[puzzle_name].append(float(row['is_amazon']))
includes_photo[puzzle_name].append(float(row['includes_photo']))
num_helpful[puzzle_name].append(float(row['num_helpful']))
labels[puzzle_name] = float(row[label_name])
# Organize data into list of list of features.
names = list(star_rating.keys())
star_rating = [star_rating[name] for name in names]
word_count = [word_count[name] for name in names]
is_amazon = [is_amazon[name] for name in names]
includes_photo = [includes_photo[name] for name in names]
num_helpful = [num_helpful[name] for name in names]
num_reviews = [[len(ratings)] * len(ratings) for ratings in star_rating]
labels = [labels[name] for name in names]
# Flatten num_reviews
flattened_features['num_reviews'] = [len(reviews) for reviews in num_reviews]
# Convert data into ragged tensors.
star_rating = tf.ragged.constant(star_rating)
word_count = tf.ragged.constant(word_count)
is_amazon = tf.ragged.constant(is_amazon)
includes_photo = tf.ragged.constant(includes_photo)
num_helpful = tf.ragged.constant(num_helpful)
num_reviews = tf.ragged.constant(num_reviews)
labels = tf.constant(labels)
# Now we can return our extracted data.
return (star_rating, word_count, is_amazon, includes_photo, num_helpful,
num_reviews), labels, flattened_features
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train_xs, train_ys, flattened_features = extract_features(train_dataframe, 'Sales12-18MonthsAgo')
test_xs, test_ys, _ = extract_features(test_dataframe, 'SalesLastSixMonths')
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# Let's define our label minimum and maximum.
min_label, max_label = float(np.min(train_ys)), float(np.max(train_ys))
min_label, max_label = float(np.min(train_ys)), float(np.max(train_ys))
Setting the default values used for training in this guide:
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LEARNING_RATE = 0.1
BATCH_SIZE = 128
NUM_EPOCHS = 500
MIDDLE_DIM = 3
MIDDLE_LATTICE_SIZE = 2
MIDDLE_KEYPOINTS = 16
OUTPUT_KEYPOINTS = 8
Feature calibration and per-feature configurations are set using tfl.configs.FeatureConfig. Feature configurations include monotonicity constraints, per-feature regularization (see tfl.configs.RegularizerConfig), and lattice sizes for lattice models.
Note that we must fully specify the feature config for any feature that we want our model to recognize. Otherwise the model will have no way of knowing that such a feature exists. For aggregation models, these features will automaticaly be considered and properly handled as ragged.
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def compute_quantiles(features,
num_keypoints=10,
clip_min=None,
clip_max=None,
missing_value=None):
# Clip min and max if desired.
if clip_min is not None:
features = np.maximum(features, clip_min)
features = np.append(features, clip_min)
if clip_max is not None:
features = np.minimum(features, clip_max)
features = np.append(features, clip_max)
# Make features unique.
unique_features = np.unique(features)
# Remove missing values if specified.
if missing_value is not None:
unique_features = np.delete(unique_features,
np.where(unique_features == missing_value))
# Compute and return quantiles over unique non-missing feature values.
return np.quantile(
unique_features,
np.linspace(0., 1., num=num_keypoints),
interpolation='nearest').astype(float)
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# Feature configs are used to specify how each feature is calibrated and used.
feature_configs = [
tfl.configs.FeatureConfig(
name='star_rating',
lattice_size=2,
monotonicity='increasing',
pwl_calibration_num_keypoints=5,
pwl_calibration_input_keypoints=compute_quantiles(
flattened_features['star_rating'], num_keypoints=5),
),
tfl.configs.FeatureConfig(
name='word_count',
lattice_size=2,
monotonicity='increasing',
pwl_calibration_num_keypoints=5,
pwl_calibration_input_keypoints=compute_quantiles(
flattened_features['word_count'], num_keypoints=5),
),
tfl.configs.FeatureConfig(
name='is_amazon',
lattice_size=2,
num_buckets=2,
),
tfl.configs.FeatureConfig(
name='includes_photo',
lattice_size=2,
num_buckets=2,
),
tfl.configs.FeatureConfig(
name='num_helpful',
lattice_size=2,
monotonicity='increasing',
pwl_calibration_num_keypoints=5,
pwl_calibration_input_keypoints=compute_quantiles(
flattened_features['num_helpful'], num_keypoints=5),
# Larger num_helpful indicating more trust in star_rating.
reflects_trust_in=[
tfl.configs.TrustConfig(
feature_name="star_rating", trust_type="trapezoid"),
],
),
tfl.configs.FeatureConfig(
name='num_reviews',
lattice_size=2,
monotonicity='increasing',
pwl_calibration_num_keypoints=5,
pwl_calibration_input_keypoints=compute_quantiles(
flattened_features['num_reviews'], num_keypoints=5),
)
]
To construct a TFL premade model, first construct a model configuration from tfl.configs. An aggregate function model is constructed using the tfl.configs.AggregateFunctionConfig. It applies piecewise-linear and categorical calibration, followed by a lattice model on each dimension of the ragged input. It then applies an aggregation layer over the output for each dimension. This is then followed by an optional output piecewise-lienar calibration.
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# Model config defines the model structure for the aggregate function model.
aggregate_function_model_config = tfl.configs.AggregateFunctionConfig(
feature_configs=feature_configs,
middle_dimension=MIDDLE_DIM,
middle_lattice_size=MIDDLE_LATTICE_SIZE,
middle_calibration=True,
middle_calibration_num_keypoints=MIDDLE_KEYPOINTS,
middle_monotonicity='increasing',
output_min=min_label,
output_max=max_label,
output_calibration=True,
output_calibration_num_keypoints=OUTPUT_KEYPOINTS,
output_initialization=np.linspace(
min_label, max_label, num=OUTPUT_KEYPOINTS))
# An AggregateFunction premade model constructed from the given model config.
aggregate_function_model = tfl.premade.AggregateFunction(
aggregate_function_model_config)
# Let's plot our model.
tf.keras.utils.plot_model(
aggregate_function_model, show_layer_names=False, rankdir='LR')
The output of each Aggregation layer is the averaged output of a calibrated lattice over the ragged inputs. Here is the model used inside the first Aggregation layer:
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aggregation_layers = [
layer for layer in aggregate_function_model.layers
if isinstance(layer, tfl.layers.Aggregation)
]
tf.keras.utils.plot_model(
aggregation_layers[0].model, show_layer_names=False, rankdir='LR')
Now, as with any other tf.keras.Model, we compile and fit the model to our data.
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aggregate_function_model.compile(
loss='mae',
optimizer=tf.keras.optimizers.Adam(LEARNING_RATE))
aggregate_function_model.fit(
train_xs, train_ys, epochs=NUM_EPOCHS, batch_size=BATCH_SIZE, verbose=False)
After training our model, we can evaluate it on our test set.
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print('Test Set Evaluation...')
print(aggregate_function_model.evaluate(test_xs, test_ys))