My most interesting areas are DL and NLP
http://cdn.aiindex.org/2018/AI%20Index%202018%20Annual%20Report.pdf
http://cdn.aiindex.org/2018/AI%20Index%202018%20Annual%20Report.pdf
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y_train shape: (911, 17) y_test shape: (449, 17)
(10000, 32, 32, 3)
Training Images: 8000 Training Labels: 8000
test_images = features[train_size:,:,:]
test_labels = labels[train_size:]
print("Test images: ", len(test_images))
print("Test labels: ", len(test_labels))
Test images: 2000 Test labels: 2000height = 32 width = 32 channels = 3 n_inputs = height * width
Placeholders for training data and labels
y = tf.placeholder(tf.int32,shape=[None],name="y")
Neural network design
TensorShape([Dimension(None), Dimension(32), Dimension(32), Dimension(32)])conv2.shape
TensorShape([Dimension(None), Dimension(16), Dimension(16), Dimension(64)])
Connect a max pooling layer
pool3 = tf.nn.max_pool(conv2,ksize=[1, 2, 2, 1],strides=[1, 2, 2, 1], padding="VALID") pool3.shape TensorShape([Dimension(None), Dimension(8), Dimension(8), Dimension(64)]) conv4 = tf.layers.conv2d(pool3, filters=128, kernel_size=4, strides=3, padding="SAME", activation=tf.nn.relu, name="conv4") conv4.shape TensorShape([Dimension(None), Dimension(3), Dimension(3), Dimension(128)])
Reshape the pooled layer to be a 1-D vector (flatten it)
pool5 = tf.nn.max_pool(conv4, ksize=[1, 2, 2, 1], strides=[1, 1, 1, 1],padding="VALID") pool5.shape TensorShape([Dimension(None), Dimension(2), Dimension(2), Dimension(128)]) pool5_flat = tf.reshape(pool5, shape=[-1, 128 * 2 * 2]) fullyconn1 = tf.layers.dense(pool5_flat, 128, activation=tf.nn.relu, name="fc1") fullyconn2 = tf.layers.dense(fullyconn1, 64, activation=tf.nn.relu, name="fc2")
Reference links: https://github.com/tflearn/tflearn/issues/57The final output layer with softmax activation
Do not apply the softmax activation to this layer. The tf.nn.sparse_softmax_cross_entropy_with_logits will apply the softmax activation as well as calculate the cross-entropy as our cost functionlogits = tf.layers.dense(fullyconn2, 10, name="output")xentropy = tf.nn.sparse_softmax_cross_entropy_with_logits(logits=logits, labels=y)
loss = tf.reduce_mean(xentropy)optimizer = tf.train.AdamOptimizer()training_op = optimizer.minimize(loss)Check correctness and accuracy of the prediction
correct = tf.nn.in_top_k(logits, y, 1) accuracy = tf.reduce_mean(tf.cast(correct, tf.float32))
- Check whether the highest probability output in logits is equal to the y-label
- Check the accuracy across all predictions (How many predictions did we get right?)
init = tf.global_variables_initializer() saver = tf.train.Saver()Set up a helper method to access training data in batches
def get_next_batch(features, labels, train_size, batch_index, batch_size): training_images = features[:train_size,:,:] training_labels = labels[:train_size] test_images = features[train_size:,:,:] test_labels = labels[train_size:] start_index = batch_index * batch_size end_index = start_index + batch_size return features[start_index:end_index,:,:], labels[start_index:end_index], test_images, test_labelsTrain and evaluate the model
n_epochs = 10 batch_size = 128 with tf.Session() as sess: init.run() for epoch in range(n_epochs): # Add this in when we want to run the training on all batches in CIFAR-10 for batch_id in range(1, 6): batch_index = 0 features, labels = load_cifar10_batch(batch_id) train_size = int(len(features) * 0.8) for iteration in range(train_size // batch_size): X_batch, y_batch, test_images, test_labels = get_next_batch(features, labels, train_size, batch_index, batch_size) batch_index += 1 sess.run(training_op, feed_dict={X: X_batch, y: y_batch, training: True}) acc_train = accuracy.eval(feed_dict={X: X_batch, y: y_batch}) acc_test = accuracy.eval(feed_dict={X: test_images, y: test_labels}) print(epoch, "Train accuracy:", acc_train, "Test accuracy:", acc_test) save_path = saver.save(sess, "./my_mnist_model")
- For smaller training data you'll find that the model performs poorly, it improves as you increase the size of the training data (use all batches)
- Ensure that dropout is enabled during training to avoid overfitting
9 Train accuracy: 0.73125 Test accuracy: 0.7135