Education
BabyWalk: Going Farther in Vision-and-Language Navigation by Taking Baby Steps
Zhu, Wang, Hu, Hexiang, Chen, Jiacheng, Deng, Zhiwei, Jain, Vihan, Ie, Eugene, Sha, Fei
Learning to follow instructions is of fundamental importance to autonomous agents for vision-and-language navigation (VLN). In this paper, we study how an agent can navigate long paths when learning from a corpus that consists of shorter ones. We show that existing state-of-the-art agents do not generalize well. To this end, we propose BabyWalk, a new VLN agent that is learned to navigate by decomposing long instructions into shorter ones (BabySteps) and completing them sequentially. A special design memory buffer is used by the agent to turn its past experiences into contexts for future steps. The learning process is composed of two phases. In the first phase, the agent uses imitation learning from demonstration to accomplish BabySteps. In the second phase, the agent uses curriculum-based reinforcement learning to maximize rewards on navigation tasks with increasingly longer instructions. We create two new benchmark datasets (of long navigation tasks) and use them in conjunction with existing ones to examine BabyWalk's generalization ability. Empirical results show that BabyWalk achieves state-of-the-art results on several metrics, in particular, is able to follow long instructions better. The codes and the datasets are released on our project page https://github.com/Sha-Lab/babywalk.
Multi-view Low-rank Preserving Embedding: A Novel Method for Multi-view Representation
Meng, Xiangzhu, Feng, Lin, Wang, Huibing
In recent years, we have witnessed a surge of interest in multi-view representation learning, which is concerned with the problem of learning representations of multi-view data. When facing multiple views that are highly related but sightly different from each other, most of existing multi-view methods might fail to fully integrate multi-view information. Besides, correlations between features from multiple views always vary seriously, which makes multi-view representation challenging. Therefore, how to learn appropriate embedding from multi-view information is still an open problem but challenging. To handle this issue, this paper proposes a novel multi-view learning method, named Multi-view Low-rank Preserving Embedding (MvLPE). It integrates different views into one centroid view by minimizing the disagreement term, based on distance or similarity matrix among instances, between the centroid view and each view meanwhile maintaining low-rank reconstruction relations among samples for each view, which could make more full use of compatible and complementary information from multi-view features. Unlike existing methods with additive parameters, the proposed method could automatically allocate a suitable weight for each view in multi-view information fusion. However, MvLPE couldn't be directly solved, which makes the proposed MvLPE difficult to obtain an analytic solution. To this end, we approximate this solution based on stationary hypothesis and normalization post-processing to efficiently obtain the optimal solution. Furthermore, an iterative alternating strategy is provided to solve this multi-view representation problem. The experiments on six benchmark datasets demonstrate that the proposed method outperforms its counterparts while achieving very competitive performance.
A Deep Neural Network for Audio Classification with a Classifier Attention Mechanism
Lu, Haoye, Zhang, Haolong, Nayak, Amit
Audio classification is considered as a challenging problem in pattern recognition. Recently, many algorithms have been proposed using deep neural networks. In this paper, we introduce a new attention-based neural network architecture called Classifier-Attention-Based Convolutional Neural Network (CAB-CNN). The algorithm uses a newly designed architecture consisting of a list of simple classifiers and an attention mechanism as a classifier selector. This design significantly reduces the number of parameters required by the classifiers and thus their complexities. In this way, it becomes easier to train the classifiers and achieve a high and steady performance. Our claims are corroborated by the experimental results. Compared to the state-of-the-art algorithms, our algorithm achieves more than 10% improvements on all selected test scores.
Provably Efficient Model-based Policy Adaptation
Song, Yuda, Mavalankar, Aditi, Sun, Wen, Gao, Sicun
The high sample complexity of reinforcement learning challenges its use in practice. A promising approach is to quickly adapt pre-trained policies to new environments. Existing methods for this policy adaptation problem typically rely on domain randomization and meta-learning, by sampling from some distribution of target environments during pre-training, and thus face difficulty on out-of-distribution target environments. We propose new model-based mechanisms that are able to make online adaptation in unseen target environments, by combining ideas from no-regret online learning and adaptive control. We prove that the approach learns policies in the target environment that can quickly recover trajectories from the source environment, and establish the rate of convergence in general settings. We demonstrate the benefits of our approach for policy adaptation in a diverse set of continuous control tasks, achieving the performance of state-of-the-art methods with much lower sample complexity.
Fairness Under Feature Exemptions: Counterfactual and Observational Measures
Dutta, Sanghamitra, Venkatesh, Praveen, Mardziel, Piotr, Datta, Anupam, Grover, Pulkit
With the growing use of AI in highly consequential domains, the quantification and removal of bias with respect to protected attributes, such as gender, race, etc., is becoming increasingly important. While quantifying bias is essential, sometimes the needs of a business (e.g., hiring) may require the use of certain features that are critical in a way that any bias that can be explained by them might need to be exempted. E.g., a standardized test-score may be a critical feature that should be weighed strongly in hiring even if biased, whereas other features, such as zip code may be used only to the extent that they do not discriminate. In this work, we propose a novel information-theoretic decomposition of the total bias (in a counterfactual sense) into a non-exempt component that quantifies the part of the bias that cannot be accounted for by the critical features, and an exempt component which quantifies the remaining bias. This decomposition allows one to check if the bias arose purely due to the critical features (inspired from the business necessity defense of disparate impact law) and also enables selective removal of the non-exempt component if desired. We arrive at this decomposition through examples that lead to a set of desirable properties (axioms) that any measure of non-exempt bias should satisfy. We demonstrate that our proposed counterfactual measure satisfies all of them. Our quantification bridges ideas of causality, Simpson's paradox, and a body of work from information theory called Partial Information Decomposition. We also obtain an impossibility result showing that no observational measure of non-exempt bias can satisfy all of the desirable properties, which leads us to relax our goals and examine observational measures that satisfy only some of these properties. We then perform case studies to show how one can train models while reducing non-exempt bias.
Python required for Data Science and Machine Learning 2020 Udemy
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11 Best Online Statistics Courses and Tutorials 2020 JA Directives
Are you looking for the Best Online Statistics Courses? Get everything you'd want to know about descriptive and inferential statistics with these statistics training's. Learning statistics is a must for a data scientist. If you want to learn computer science, you will need to know the statistics as well. Do you know, What is the importance of statistics? What is the importance of statistics in daily life?
Top 5 Data Science and Machine Learning degrees you can earn Online - Best of Lot
Hello guys, I have been sharing some online degree programs you can take online from last a couple of weeks as more and more people are looking for online technical degree programs. Earlier, I have shared Top 5 Computer Science degree you can earn online, and today, I will share the top 5 Data Science and Machine learning degrees you can earn online from the world's reputed universities. Data Science is the way or the process of extracting insights and useful information from your data to understand different things and turn that data into a story in the shape of graphs and a dashboard that anyone can understand and by using many different programming languages like Python and R. But imagine if you can earn an online degree in this topic, that's what we are covering in this article. The field of Data Science is one of the standard in-demand fields in today's world, and some of the people called the future career or job since the world demands people who can obtain valuable insight from data to produce a better application or for a better understanding of the world and here comes the job for a data scientist.
Drone Delivery Service to Drop Books for Virginia Students
Students aren't able to visit school libraries during the summer months anyway, but the pandemic has made it especially hard for many families to keep getting free reading material until public libraries reopen. Wing's library book delivery service is available to any of the roughly 600 students in the district who live in the delivery area. They won't have to return the books until school starts up again in the fall, Passek said.
Fundamental Data Structures & Algorithms using C language.
Recursion, Stack, Polish Notations, infix to postfix, FIFO Queue, Circular Queue, Double Ended Queue, Linked List - Linear, double and Circular - all operations, Stack and Queue using Linked List What is stack, algorithms for Push and Pop operation. Implementation of Stack data structure using C. Using Stack - checking parenthesis in an expression Using Stack - Understanding Polish notations, algorithm and implementation of infix to postfix conversion and evaluation of postfix expression What is a FIFO Queue, understanding Queue operations - Insert and delete, implementing FIFO Queue Limitations of FIFO queue, concept of Circular Queue - Implementation of Circular queue. Concept of Double ended queue, logic development and implementation of double ended queue. Concept of Linked List - definition, why we need linked list. Singly Linked List - developing algorithms for various methods and then implementing them using C programming Doubly Linked List - developing algorithm of various methods and then implementing them using C programming Circular Linked List - developing algorithm of various methods and then implementing them using C programming How to estimate time complexity of any algorithm.