Python으로 시작하는 TensorFlow
Isaiah Hull
Visiting Associate Professor of Finance, BI Norwegian Business School




확률적 경사 하강법(SGD) 최적화기
tf.keras.optimizers.SGD()learning_rate단순하고 해석이 용이
제곱평균제곱근(RMS) 전파 최적화기
tf.keras.optimizers.RMSprop()learning_ratemomentumdecay모멘텀의 축적과 감소를 모두 허용
Adaptive Moment(Adam) 최적화기
tf.keras.optimizers.Adam()learning_ratebeta1기본 하이퍼파라미터만으로도 성능 우수
import tensorflow as tf
# Define the model function
def model(bias, weights, features = borrower_features):
product = tf.matmul(features, weights)
return tf.keras.activations.sigmoid(product+bias)
# Compute the predicted values and loss
def loss_function(bias, weights, targets = default, features = borrower_features):
predictions = model(bias, weights)
return tf.keras.losses.binary_crossentropy(targets, predictions)
# Minimize the loss function with RMS propagation
opt = tf.keras.optimizers.RMSprop(learning_rate=0.01, momentum=0.9)
opt.minimize(lambda: loss_function(bias, weights), var_list=[bias, weights])
Python으로 시작하는 TensorFlow