Education
Engagement During Pandemic Teaching
In this panel, AI faculty with experience teaching online and blended classes were asked to share their experiences teaching online classes. The panel was composed of Ashok Goel, Georgia Institute of Technology, Ansaf Salleb-Aouissi, Columbia University and Mehran Sahami, Stanford University. The panelists were asked to describe which tools and methods work well to help instructors engage and bond with students online. They were furthermore asked to share their insights into which components of a course can be done best online and which ones are best accomplished in person. The panel took place as part of the 2021 Symposium on Educational Advances of AI, which was collocated with AAAI-21.
Toward deep-learning models that can reason about code more like humans
Whatever business a company may be in, software plays an increasingly vital role, from managing inventory to interfacing with customers. Software developers, as a result, are in greater demand than ever, and that's driving the push to automate some of the easier tasks that take up their time. Productivity tools like Eclipse and Visual Studio suggest snippets of code that developers can easily drop into their work as they write. These automated features are powered by sophisticated language models that have learned to read and write computer code after absorbing thousands of examples. But like other deep learning models trained on big datasets without explicit instructions, language models designed for code-processing have baked-in vulnerabilities.
IIT Roorkee launches Online Certificate Programs in Data Science and Machine Learning on Coursera
Roorkee: Indian Institute of Technology (IIT) Roorkee has launched two online certificate programs in high-demand topics -- Data Science and Machine Learning and Advanced Machine Learning and AI -- on Coursera, one of the world's leading online learning platform. "We are happy to announce two certificate courses in data science, machine learning, and AI in partnership with Coursera. This will enable a large number of aspirants to acquire these relevant areas for their professional growth," said Prof. Ajit K. Chaturvedi, Director, IIT Roorkee IIT Roorkee is among 150 top universities, including Yale, University of Michigan, University of Pennsylvania, and Imperial College of London -- that offer programs on Coursera. "For over 170 years, IIT Roorkee has been a leading Indian institution, known for its rigorous technical programs," said Betty Vandenbosch, Chief Content Officer at Coursera. "Through our partnership, we are expanding access and allowing more students to learn from IIT Roorkee's renowned faculty. Learners will gain the cutting-edge skills they need to advance their careers while creating powerful networks with their peers."
The Place for Artificial Intelligence in Education
Technology's impact on the educational world strengthens with each year. Among many other developments, artificial intelligence seems to be an up-and-coming trend. It is clear that great changes are coming, and machines will take a direct role in them. Schools and universities will never return to the original format. Many wonder whether robots will replace professors, whether the effects of progress will be positive or negative and what should be done to improve current teaching approaches.
Randomized Algorithms for Scientific Computing (RASC)
Buluc, Aydin, Kolda, Tamara G., Wild, Stefan M., Anitescu, Mihai, DeGennaro, Anthony, Jakeman, John, Kamath, Chandrika, Ramakrishnan, null, Kannan, null, Lopes, Miles E., Martinsson, Per-Gunnar, Myers, Kary, Nelson, Jelani, Restrepo, Juan M., Seshadhri, C., Vrabie, Draguna, Wohlberg, Brendt, Wright, Stephen J., Yang, Chao, Zwart, Peter
Randomized algorithms have propelled advances in artificial intelligence and represent a foundational research area in advancing AI for Science. Future advancements in DOE Office of Science priority areas such as climate science, astrophysics, fusion, advanced materials, combustion, and quantum computing all require randomized algorithms for surmounting challenges of complexity, robustness, and scalability. This report summarizes the outcomes of that workshop, "Randomized Algorithms for Scientific Computing (RASC)," held virtually across four days in December 2020 and January 2021.
Modeling Classroom Occupancy using Data of WiFi Infrastructure in a University Campus
Mohottige, Iresha Pasquel, Gharakheili, Hassan Habibi, Sivaraman, Vijay, Moors, Tim
Universities worldwide are experiencing a surge in enrollments, therefore campus estate managers are seeking continuous data on attendance patterns to optimize the usage of classroom space. As a result, there is an increasing trend to measure classrooms attendance by employing various sensing technologies, among which pervasive WiFi infrastructure is seen as a low cost method. In a dense campus environment, the number of connected WiFi users does not well estimate room occupancy since connection counts are polluted by adjoining rooms, outdoor walkways, and network load balancing. In this paper, we develop machine learning based models to infer classroom occupancy from WiFi sensing infrastructure. Our contributions are three-fold: (1) We analyze metadata from a dense and dynamic wireless network comprising of thousands of access points (APs) to draw insights into coverage of APs, behavior of WiFi connected users, and challenges of estimating room occupancy; (2) We propose a method to automatically map APs to classrooms using unsupervised clustering algorithms; and (3) We model classroom occupancy using a combination of classification and regression methods of varying algorithms. We achieve 84.6% accuracy in mapping APs to classrooms while the accuracy of our estimation for room occupancy is comparable to beam counter sensors with a symmetric Mean Absolute Percentage Error (sMAPE) of 13.10%.
Reinforcement learning for linear-convex models with jumps via stability analysis of feedback controls
Guo, Xin, Hu, Anran, Zhang, Yufei
We study finite-time horizon continuous-time linear-convex reinforcement learning problems in an episodic setting. In this problem, the unknown linear jump-diffusion process is controlled subject to nonsmooth convex costs. We show that the associated linear-convex control problems admit Lipchitz continuous optimal feedback controls and further prove the Lipschitz stability of the feedback controls, i.e., the performance gap between applying feedback controls for an incorrect model and for the true model depends Lipschitz-continuously on the magnitude of perturbations in the model coefficients; the proof relies on a stability analysis of the associated forward-backward stochastic differential equation. We then propose a novel least-squares algorithm which achieves a regret of the order $O(\sqrt{N\ln N})$ on linear-convex learning problems with jumps, where $N$ is the number of learning episodes; the analysis leverages the Lipschitz stability of feedback controls and concentration properties of sub-Weibull random variables.
Knowledge Distillation as Semiparametric Inference
Dao, Tri, Kamath, Govinda M, Syrgkanis, Vasilis, Mackey, Lester
A popular approach to model compression is to train an inexpensive student model to mimic the class probabilities of a highly accurate but cumbersome teacher model. Surprisingly, this two-step knowledge distillation process often leads to higher accuracy than training the student directly on labeled data. To explain and enhance this phenomenon, we cast knowledge distillation as a semiparametric inference problem with the optimal student model as the target, the unknown Bayes class probabilities as nuisance, and the teacher probabilities as a plug-in nuisance estimate. By adapting modern semiparametric tools, we derive new guarantees for the prediction error of standard distillation and develop two enhancements -- cross-fitting and loss correction -- to mitigate the impact of teacher overfitting and underfitting on student performance. We validate our findings empirically on both tabular and image data and observe consistent improvements from our knowledge distillation enhancements.
Continual Learning with Fully Probabilistic Models
Pfülb, Benedikt, Gepperth, Alexander, Bagus, Benedikt
We present an approach for continual learning (CL) that is based on fully probabilistic (or generative) models of machine learning. In contrast to, e.g., GANs that are "generative" in the sense that they can generate samples, fully probabilistic models aim at modeling the data distribution directly. Consequently, they provide functionalities that are highly relevant for continual learning, such as density estimation (outlier detection) and sample generation. As a concrete realization of generative continual learning, we propose Gaussian Mixture Replay (GMR). GMR is a pseudo-rehearsal approach using a Gaussian Mixture Model (GMM) instance for both generator and classifier functionalities. Relying on the MNIST, FashionMNIST and Devanagari benchmarks, we first demonstrate unsupervised task boundary detection by GMM density estimation, which we also use to reject untypical generated samples. In addition, we show that GMR is capable of class-conditional sampling in the way of a cGAN. Lastly, we verify that GMR, despite its simple structure, achieves state-of-the-art performance on common class-incremental learning problems at very competitive time and memory complexity.
Mixtures of Gaussian Processes for regression under multiple prior distributions
When constructing a Bayesian Machine Learning model, we might be faced with multiple different prior distributions and thus are required to properly consider them in a sensible manner in our model. While this situation is reasonably well explored for classical Bayesian Statistics, it appears useful to develop a corresponding method for complex Machine Learning problems. Given their underlying Bayesian framework and their widespread popularity, Gaussian Processes are a good candidate to tackle this task. We therefore extend the idea of Mixture models for Gaussian Process regression in order to work with multiple prior beliefs at once - both a analytical regression formula and a Sparse Variational approach are considered. In addition, we consider the usage of our approach to additionally account for the problem of prior misspecification in functional regression problems.