self.global_step = tf.Variable(0, trainable=False)
  self.train_op = tf.train.RMSPropOptimizer(learning_rate=0.01, decay=0.8).minimize(self.mean_loss)
  self.init = tf.global_variables_initializer()

  # Initialize coefficients
  self.sess = tf.Session()
  self.sess.run(self.init)