Education
Real-Time Cognitive Evaluation of Online Learners through Automatically Generated Questions
Gala, Ritu, Vijayaraghavan, Revathi, Nikam, Valmik, Kiwelekar, Arvind
With the increased adoption of E-learning platforms, keeping online learners engaged throughout a lesson is challenging. One approach to tackle this challenge is to probe learn-ers periodically by asking questions. The paper presents an approach to generate questions from a given video lecture automatically. The generated questions are aimed to evaluate learners' lower-level cognitive abilities. The approach automatically extracts text from video lectures to generates wh-kinds of questions. When learners respond with an answer, the proposed approach further evaluates the response and provides feedback. Besides enhancing learner's engagement, this approach's main benefits are that it frees instructors from design-ing questions to check the comprehension of a topic. Thus, instructors can spend this time productively on other activities.
Neural Tangent Kernel Maximum Mean Discrepancy
We present a novel neural network Maximum Mean Discrepancy (MMD) statistic by identifying a connection between neural tangent kernel (NTK) and MMD statistic. This connection enables us to develop a computationally efficient and memory-efficient approach to compute the MMD statistic and perform neural network based two-sample tests towards addressing the long-standing challenge of memory and computational complexity of the MMD statistic, which is essential for online implementation to assimilate new samples. Theoretically, such a connection allows us to understand the properties of the new test statistic, such as Type-I error and testing power for performing the two-sample test, by leveraging analysis tools for kernel MMD. Numerical experiments on synthetic and real-world datasets validate the theory and demonstrate the effectiveness of the proposed NTK-MMD statistic.
Meta-Learning Reliable Priors in the Function Space
Rothfuss, Jonas, Heyn, Dominique, Chen, Jinfan, Krause, Andreas
Meta-Learning promises to enable more data-efficient inference by harnessing previous experience from related learning tasks. While existing meta-learning methods help us to improve the accuracy of our predictions in face of data scarcity, they fail to supply reliable uncertainty estimates, often being grossly overconfident in their predictions. Addressing these shortcomings, we introduce a novel meta-learning framework, called F-PACOH, that treats meta-learned priors as stochastic processes and performs meta-level regularization directly in the function space. This allows us to directly steer the probabilistic predictions of the meta-learner towards high epistemic uncertainty in regions of insufficient meta-training data and, thus, obtain well-calibrated uncertainty estimates. Finally, we showcase how our approach can be integrated with sequential decision making, where reliable uncertainty quantification is imperative. In our benchmark study on meta-learning for Bayesian Optimization (BO), F-PACOH significantly outperforms all other meta-learners and standard baselines. Even in a challenging lifelong BO setting, where optimization tasks arrive one at a time and the meta-learner needs to build up informative prior knowledge incrementally, our proposed method demonstrates strong positive transfer.
Bridging the gender digital divide: AI Hackathon with Microsoft supports girls' digital skills
Or so Hesme, aged 15, believed when she switched schools in 10th grade. "I thought I'd be terrible at it", she says. When she moved to Curro Heritage House High School, STEM classes were a regular part of the curriculum. She was nervous about that โ but when her brother dared her to take a computer science class, she accepted the challenge to prove him wrong. Hesme loved her computer science class.
Top 10 machine learning startups in 2021 edition 2
Founders Heu.ai 2. rpasaerialsolutions.com 3. Swiftnlift Media And Tech SwiftNLift is the Best Business Magazine across the globe for enterprises. I am really encouraged by the feedback received from the readers and the institutions which are in association with our magazine. Many thanks to my team for the work undertaken. I'm very glad to present this magazine to all the readers. The cover story has featured I Pavan Raju (Director) of Heu Technologies Private Limited. It is a platform for artificial intelligence solutions that empowers ventures to upgrade their business by solving challenging problems and enhancing them. Some print pieces have complementary components such as additional coverage, advertisements and still photography. There are regular columns by the editors with reflective articles to provide a window Artificial Intelligence and its features. Swiftnlift Magazine is not just a print or digital anymore but everything we do derives from its long-standing character, ...
How Chatbots can be a Game Changer for Educational Mobile Apps?
The educational sector has undergone massive changes post the proliferation of internet services in learning. It will not be an exaggeration to say that they have completely changed the way students of all ages study, and the overall landscape of education has evolved for good. With Education App Development Companies coming in, there are a host of online educational mobile apps for readers of every age. Schools also recommend online educational mobile app these days to reinforce and supplement in-class sessions. Research suggests that the size of educational mobile apps is going to rise by CAGR of more than 27% by 2022, which marks it as one of the fastest-growing segments in mobile apps.
Same State, Different Task: Continual Reinforcement Learning without Interference
Kessler, Samuel, Parker-Holder, Jack, Ball, Philip, Zohren, Stefan, Roberts, Stephen J.
Continual Learning (CL) considers the problem of training an agent sequentially on a set of tasks while seeking to retain performance on all previous tasks. A key challenge in CL is catastrophic forgetting, which arises when performance on a previously mastered task is reduced when learning a new task. While a variety of methods exist to combat forgetting, in some cases tasks are fundamentally incompatible with each other and thus cannot be learnt by a single policy. This can occur, in reinforcement learning (RL) when an agent may be rewarded for achieving different goals from the same observation. In this paper we formalize this ``interference'' as distinct from the problem of forgetting. We show that existing CL methods based on single neural network predictors with shared replay buffers fail in the presence of interference. Instead, we propose a simple method, OWL, to address this challenge. OWL learns a factorized policy, using shared feature extraction layers, but separate heads, each specializing on a new task. The separate heads in OWL are used to prevent interference. At test time, we formulate policy selection as a multi-armed bandit problem, and show it is possible to select the best policy for an unknown task using feedback from the environment. The use of bandit algorithms allows the OWL agent to constructively re-use different continually learnt policies at different times during an episode. We show in multiple RL environments that existing replay based CL methods fail, while OWL is able to achieve close to optimal performance when training sequentially.
Solving hybrid machine learning tasks by traversing weight space geodesics
Raghavan, Guruprasad, Thomson, Matt
Machine learning problems have an intrinsic geometric structure as central objects including a neural network's weight space and the loss function associated with a particular task can be viewed as encoding the intrinsic geometry of a given machine learning problem. Therefore, geometric concepts can be applied to analyze and understand theoretical properties of machine learning strategies as well as to develop new algorithms. In this paper, we address three seemingly unrelated open questions in machine learning by viewing them through a unified framework grounded in differential geometry. Specifically, we view the weight space of a neural network as a manifold endowed with a Riemannian metric that encodes performance on specific tasks. By defining a metric, we can construct geodesic, minimum length, paths in weight space that represent sets of networks of equivalent or near equivalent functional performance on a specific task. We, then, traverse geodesic paths while identifying networks that satisfy a second objective. Inspired by the geometric insight, we apply our geodesic framework to 3 major applications: (i) Network sparsification (ii) Mitigating catastrophic forgetting by constructing networks with high performance on a series of objectives and (iii) Finding high-accuracy paths connecting distinct local optima of deep networks in the non-convex loss landscape. Our results are obtained on a wide range of network architectures (MLP, VGG11/16) trained on MNIST, CIFAR-10/100. Broadly, we introduce a geometric framework that unifies a range of machine learning objectives and that can be applied to multiple classes of neural network architectures.
Regret Minimization Experience Replay
Xue, Zhenghai, Liu, Xu-Hui, Pang, Jing-Cheng, Jiang, Shengyi, Xu, Feng, Yu, Yang
In reinforcement learning, experience replay stores past samples for further reuse. Prioritized sampling is a promising technique to better utilize these samples. Previous criteria of prioritization include TD error, recentness and corrective feedback, which are mostly heuristically designed. In this work, we start from the regret minimization objective, and obtain an optimal prioritization strategy for Bellman update that can directly maximize the return of the policy. The theory suggests that data with higher hindsight TD error, better on-policiness and more accurate Q value should be assigned with higher weights during sampling. Thus most previous criteria only consider this strategy partially. We not only provide theoretical justifications for previous criteria, but also propose two new methods to compute the prioritization weight, namely ReMERN and ReMERT. ReMERN learns an error network, while ReMERT exploits the temporal ordering of states. Both methods outperform previous prioritized sampling algorithms in challenging RL benchmarks, including MuJoCo, Atari and Meta-World.