AutoML Library for Regression : AutoKeras

What is AutoKeras?

It is an open-source AutoML system based on Keras.

What’s AutoML ? Well, it will make your life easy by finding out the best-performing model for a given dataset.

We will look at how it can done.

Install AutoKeras :

!pip install autokeras

Import Necessary Modules :

import numpy as np
import pandas as pd
import plotly.express as px
from autokeras import StructuredDataRegressor
from sklearn.model_selection import train_test_split
from IPython.display import HTML

Let’s take a simple sales data ,

df = pd.read_csv("Data.csv")
df.head()

Sales is the dependent variable and TV, Radio, Newspaper are independent variable

Split Data :

target_col = "sales"
X = df.loc[:, df.columns != target_col]
y = df.loc[:, target_col]
# Train test split 
X_train, X_test, y_train, y_test = train_test_split(X, y, 
                                                    test_size=0.20, 
                                                    random_state=2021)

Now let’s train our model, Autokeras will find out the best possible model, this is achieved by StructuredDataRegressor class defined by AutoKeras library.

# max trials tries 15 different models, MAE is the loss function
search = StructuredDataRegressor(max_trials=15, loss='mean_absolute_error')
# Fitting our training data to the model class 
search.fit(x=X_train, y=y_train)
# You can also add Keras Callbacks while fitting to model class
tensorboard_callback = tf.keras.callbacks.TensorBoard(log_dir='./logs', histogram_freq=0,
write_graph=True, write_images=False)
search.fit(x = X_train, y = y_train, epochs = 50,callbacks = [tensorboard_callback], validation_data=(X_test,y_test))

This can take a few minutes depending on the system..

Evaluate the model on train and test data to see how it performs :

train_mae, _ = search.evaluate(X_train, y_train, verbose=0)
print('Mean Absolute Error is {}'.format(train_mae))
test_mae, _ = search.evaluate(X_test, y_test, verbose=0)
print('Mean Absolute Error is {}'.format(test_mae))

Save the model :

model = search.export_model()
# To view the model summary
model.summary()
try:
model.save("model_autokeras", save_format="tf")
except Exception:
model.save("model_autokeras.h5")

Load the saved model for prediction :

from tensorflow.keras.models import load_model
loaded_model = load_model("model_autokeras", custom_objects=autokeras.CUSTOM_OBJECTS)
predicted_y = loaded_model.predict(tf.expand_dims(X_test, -1))

Link to GitHub : https://github.com/amalaj7/AutoKeras-Regression

Hope you learned something new today, Happy Learning!