Best Practices for Preparing & Augmenting Images for Convolutional Neural Networks

Best Practices for Preparing & Augmenting Images for Convolutional Neural Networks

Here’s an interesting tutorial on prepping image data for CNNs.

It is challenging to know how to best prepare image data when training a convolutional neural network. This involves both scaling the pixel values and use of augmentation techniques during both the training and evaluation of the model. Instead of testing a wide range of options, a useful shortcut […]

How to Avoid Overfitting in Deep Learning Neural Networks

How to Avoid Overfitting in Deep Learning Neural Networks

Here’s a great article on avoiding overfitting in deep neural networks.

No one is too legit to overfit.

Training a deep neural network that can generalize well to new data is a challenging problem. A model with too little capacity cannot learn the problem, whereas a model with too much capacity can learn it too well and overfit the training dataset. Both cases result in a model […]

In Praise of the Autoencoder

In Praise of the Autoencoder

Of all the machine learning algorithms, the most fascinating are neural networks. They don’t require statistical hypothesis or rigorous data preparation save for normalization.

The power of a neural network lies in its architecture, its activation functions, its regularization, etc.

Here’s an interesting article exploring a particular kind of neural network: the autoencoder.

Fraud Detection Using a Neural Autoencoder

Fraud detection, a common use of AI, belongs to a more general class of problems — anomaly detection.

An anomaly is a generic, not domain-specific, concept. It refers to any exceptional or unexpected event in the data: a mechanical piece failure, an arrhythmic heartbeat, or a fraudulent transaction.

Basically, identifying a fraud means identifying an anomaly in the realm of a set of legitimate transactions. Like all anomalies, you can never be truly sure of the form a fraudulent transaction will take on. You need to take all possible “unknown” forms into account.

Here’s an interesting article on doing anomaly/fraud detection with a neural autoencoder.

Using a training set of just legitimate transactions, we teach a machine learning algorithm to reproduce the feature vector of each transaction. Then we perform a reality check on such a reproduction. If the distance between the original transaction and the reproduced transaction is below a given threshold, the transaction is considered legitimate; otherwise it is considered a fraud candidate (generative approach). In this case, we just need a training set of “normal” transactions, and we suspect an anomaly from the distance value.

Based on the histograms or on the box plots of the input features, a threshold can be identified. All transactions with input features beyond that threshold will be declared fraud candidates (discriminative approach). Usually, for this approach, a number of fraud and legitimate transaction examples are necessary to build the histograms or the box plots.

Artificial Intelligence Beyond Deep Neural Networks

Artificial Intelligence Beyond Deep Neural Networks

Here’s an interesting look at the cutting edge technologies just on the horizon of AI research and what problems they can potentially solve that current techniques can’t.

Artificial intelligence (AI) is dominated by pattern recognition techniques. Recently, major advances have been made in the fields of image recognition, machine translation, audio processing and several others thanks to the development and refinement of deep learning. But deep learning is not the cure for every problem. In fact, […]

Physicists Train Oscillatory Neural Network to Recognize Images

Physicists Train Oscillatory Neural Network to Recognize Images

Here’s an interesting article on “oscillatory neural networks” and how physicists trained it to perform image recognition.

An oscillatory neural network is a complex interlacing of interacting elements (oscillators) that are able to receive and transmit oscillations of a certain frequency. Receiving signals of various frequencies from preceding elements, the artificial neuron oscillator can synchronize its rhythm with these fluctuations. As a result, […]

Google Open-Sources Library for Efficiently Training Large Deep Neural Nets

Google Open-Sources Library for Efficiently Training Large Deep Neural Nets

Last last week, Google’s AI research division open-sourced GPipe, a library for “efficiently” training deep neural networks under Lingvo, a TensorFlow framework for sequence modeling.

Most of GPipe’s performance gains come from better memory allocation for AI models. On second-generation Google Cloud tensor processing units (TPUs), each of which contains eight processor cores and 64 GB memory (8 GB per core), GPipe reduced intermediate memory usage from 6.26 GB to 3.46GB, enabling 318 million parameters on a single accelerator core. Without GPipe, Huang says, a single core can only train up to 82 million model parameters.

Shark or Baseball? Inside the ‘Black Box’ of a Neural Network

Shark or Baseball? Inside the ‘Black Box’ of a Neural Network

Generally speaking, Neural Networks are somewhat of a mystery. While you can understand the mechanics and the math that powers them, exactly how the network comes to its conclusions are a bit of a black box.

Here’s an interesting story on how researchers are trying to peer into the mysteries of a neural net.

Using an “activation atlas,” researchers can plumb the hidden depths of a neural network and study how it learns visual concepts. Shan Carter, a researcher at Google Brain, recently visited his daughter’s second-grade class with an unusual payload: an array of psychedelic pictures filled with indistinct shapes and warped […]