Education
'This is bigger than just Timnit': How Google tried to silence a critic and ignited a movement
Timnit Gebru--a giant in the world of AI and then co-lead of Google's AI ethics team--was pushed out of her job in December. Gebru had been fighting with the company over a research paper that she'd coauthored, which explored the risks of the AI models that the search giant uses to power its core products--the models are involved in almost every English query on Google, for instance. The paper called out the potential biases (racial, gender, Western, and more) of these language models, as well as the outsize carbon emissions required to compute them. Google wanted the paper retracted, or any Google-affiliated authors' names taken off; Gebru said she would do so if Google would engage in a conversation about the decision. Instead, her team was told that she had resigned. After the company abruptly announced Gebru's departure, Google AI chief Jeff Dean insinuated that her work was not up to snuff--despite Gebru's credentials and history of groundbreaking research.
10 Must Read ML Blog Posts
I have been doing NLP/ML research for the last 6 years. I have come across a lot of machine learning resources and papers. Today, I kept thinking about the machine learning / NLP / deep learning related blog posts (not papers) that have been transformational for me. In this blog post, I provide a short collection of a few high-impact blog posts that come to mind. This post was originally a Twitter thread.
KANDINSKYPatterns -- An experimental exploration environment for Pattern Analysis and Machine Intelligence
Holzinger, Andreas, Saranti, Anna, Mueller, Heimo
Machine intelligence is very successful at standard recognition tasks when having high-quality training data. There is still a significant gap between machine-level pattern recognition and human-level concept learning. Humans can learn under uncertainty from only a few examples and generalize these concepts to solve new problems. The growing interest in explainable machine intelligence, requires experimental environments and diagnostic tests to analyze weaknesses in existing approaches to drive progress in the field. In this paper, we discuss existing diagnostic tests and test data sets such as CLEVR, CLEVERER, CLOSURE, CURI, Bongard-LOGO, V-PROM, and present our own experimental environment: The KANDINSKYPatterns, named after the Russian artist Wassily Kandinksy, who made theoretical contributions to compositivity, i.e. that all perceptions consist of geometrically elementary individual components. This was experimentally proven by Hubel &Wiesel in the 1960s and became the basis for machine learning approaches such as the Neocognitron and the even later Deep Learning. While KANDINSKYPatterns have computationally controllable properties on the one hand, bringing ground truth, they are also easily distinguishable by human observers, i.e., controlled patterns can be described by both humans and algorithms, making them another important contribution to international research in machine intelligence.
Feedback Coding for Active Learning
Canal, Gregory, Bloch, Matthieu, Rozell, Christopher
Active learning is an area of modern machine learning that studies how data points can be sequentially selected for labeling to train a model with as few labeled examples as possible (Settles, 2009). Minimizing the number of labeled examples is critical in any learning scenario where labels are expensive to obtain, such as in healthcare applications where a medical expert must hand-label each training example (Liu, 2004), or where only a limited number of examples can be evaluated, such as in drug discovery (Warmuth et al., 2003). The active selection of data points shares many technical parallels with channel coding with feedback, where a message is encoded into a sequence of symbols transmitted across a noisy channel and each symbol is selected based on the message and past channel outputs. In active learning, the optimal classifier parameters play the role of the "message" while the sequence of examples with noisy labels plays the role of "channel outputs" available through feedback to select the next example for labeling. Both feedback channel coding and active learning seek to minimize the number of encoder actions, leverage a history of noisy observations to select the next most informative action, must account for observation noise, and should operate in a computationally efficient manner. Although there exists a large literature studying the intersection of information theory with machine learning (Xu and Raginsky, 2017) and specifically active learning (Naghshvar et al., 2015), there remain open questions about the best ways to directly leverage techniques in channel coding for active example selection. The main contribution of this work is a formulation of general active learning problems in terms of a feedback coding system, and a demonstration of this approach through the application and analysis of active learning in logistic regression. To motivate this approach, we first examine active learning through the lens of feedback channel coding by identifying communications system components, including a deterministic encoder, noisy channel, channel input constraints, and capacity-achieving distribution. With these components identified, we show how typical structural constraints in active learning problems prevent the direct application of existing feedback coding approaches such as posterior matching (Ma and Coleman, 2011).
Distilling Knowledge via Intermediate Classifier Heads
Asadian, Aryan, Salehi-Abari, Amirali
The crux of knowledge distillation -- as a transfer-learning approach -- is to effectively train a resource-limited student model with the guide of a pre-trained larger teacher model. However, when there is a large difference between the model complexities of teacher and student (i.e., capacity gap), knowledge distillation loses its strength in transferring knowledge from the teacher to the student, thus training a weaker student. To mitigate the impact of the capacity gap, we introduce knowledge distillation via intermediate heads. By extending the intermediate layers of the teacher (at various depths) with classifier heads, we cheaply acquire a cohort of heterogeneous pre-trained teachers. The intermediate classifier heads can all together be efficiently learned while freezing the backbone of the pre-trained teacher. The cohort of teachers (including the original teacher) co-teach the student simultaneously. Our experiments on various teacher-student pairs and datasets have demonstrated that the proposed approach outperforms the canonical knowledge distillation approach and its extensions.
SpikeDyn: A Framework for Energy-Efficient Spiking Neural Networks with Continual and Unsupervised Learning Capabilities in Dynamic Environments
Putra, Rachmad Vidya Wicaksana, Shafique, Muhammad
Spiking Neural Networks (SNNs) bear the potential of efficient unsupervised and continual learning capabilities because of their biological plausibility, but their complexity still poses a serious research challenge to enable their energy-efficient design for resource-constrained scenarios (like embedded systems, IoT-Edge, etc.). We propose SpikeDyn, a comprehensive framework for energy-efficient SNNs with continual and unsupervised learning capabilities in dynamic environments, for both the training and inference phases. It is achieved through the following multiple diverse mechanisms: 1) reduction of neuronal operations, by replacing the inhibitory neurons with direct lateral inhibitions; 2) a memory- and energy-constrained SNN model search algorithm that employs analytical models to estimate the memory footprint and energy consumption of different candidate SNN models and selects a Pareto-optimal SNN model; and 3) a lightweight continual and unsupervised learning algorithm that employs adaptive learning rates, adaptive membrane threshold potential, weight decay, and reduction of spurious updates. Our experimental results show that, for a network with 400 excitatory neurons, our SpikeDyn reduces the energy consumption on average by 51% for training and by 37% for inference, as compared to the state-of-the-art. Due to the improved learning algorithm, SpikeDyn provides on avg. 21% accuracy improvement over the state-of-the-art, for classifying the most recently learned task, and by 8% on average for the previously learned tasks.
Understanding Robustness in Teacher-Student Setting: A New Perspective
Yang, Zhuolin, Chen, Zhaoxi, Cai, Tiffany, Chen, Xinyun, Li, Bo, Tian, Yuandong
Adversarial examples have appeared as a ubiquitous property of machine learning models where bounded adversarial perturbation could mislead the models to make arbitrarily incorrect predictions. Such examples provide a way to assess the robustness of machine learning models as well as a proxy for understanding the model training process. Extensive studies try to explain the existence of adversarial examples and provide ways to improve model robustness (e.g. adversarial training). While they mostly focus on models trained on datasets with predefined labels, we leverage the teacher-student framework and assume a teacher model, or oracle, to provide the labels for given instances. We extend Tian (2019) in the case of low-rank input data and show that student specialization (trained student neuron is highly correlated with certain teacher neuron at the same layer) still happens within the input subspace, but the teacher and student nodes could differ wildly out of the data subspace, which we conjecture leads to adversarial examples. Extensive experiments show that student specialization correlates strongly with model robustness in different scenarios, including student trained via standard training, adversarial training, confidence-calibrated adversarial training, and training with robust feature dataset. Our studies could shed light on the future exploration about adversarial examples, and enhancing model robustness via principled data augmentation.
Teach Me to Explain: A Review of Datasets for Explainable NLP
Wiegreffe, Sarah, Marasoviฤ, Ana
Explainable NLP (ExNLP) has increasingly focused on collecting human-annotated explanations. These explanations are used downstream in three ways: as data augmentation to improve performance on a predictive task, as a loss signal to train models to produce explanations for their predictions, and as a means to evaluate the quality of model-generated explanations. In this review, we identify three predominant classes of explanations (highlights, free-text, and structured), organize the literature on annotating each type, point to what has been learned to date, and give recommendations for collecting ExNLP datasets in the future.
Newbie's Deep Learning Tutorial: Learn Keras Machine Learning
Keras is a high-level API, which is aimed to build and train deep learning with Python. This tutorial is created by data scientist and app developer Nimish Narang, which already created more than 20 Mammoth Interactive courses - online tutorials about the web, app, and game development. Python deep learning tutorial is for you if you want to learn the concept of machine learning with practical tasks using Keras, Python, and PyCharm. Any person who understands that technologies shape the way of communication should enroll in this deep learning tutorial for beginners as well. Trust me, after completing this course, new possibilities will open up, as you'll get a new set of skills on new technologies, which are the skills that many employers are looking for. So don't wait up and enroll in this Python machine learning tutorial right away!
Artificial Neural Networks (ANN) with Keras in Python and R
Artificial Neural Networks (ANN) with Keras in Python and R, Understand Deep Learning and build Neural Networks using TensorFlow 2.0 and Keras in Python and R Created by Start-Tech AcademyPreview this Course - GET COUPON CODE You're looking for a complete Course on Deep Learning using Keras and Tensorflow that teaches you everything you need to create a Neural Network model in Python and R, right? You've found the right Neural Networks course! After completing this course you will be able to: Identify the business problem which can be solved using Neural network Models. Have a clear understanding of Advanced Neural network concepts such as Gradient Descent, forward and Backward Propagation etc. Create Neural network models in Python and R using Keras and Tensorflow libraries and analyze their results. Confidently practice, discuss and understand Deep Learning concepts How this course will help you?