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A step towards the applicability of algorithms based on invariant causal learning on observational data

arXiv.org Artificial Intelligence

Machine learning can benefit from causal discovery for interpretation and from causal inference for generalization. In this line of research, a few invariant learning algorithms for out-of-distribution (OOD) generalization have been proposed by using multiple training environments to find invariant relationships. Some of them are focused on causal discovery as Invariant Causal Prediction (ICP), which finds causal parents of a variable of interest, and some directly provide a causal optimal predictor that generalizes well in OOD environments as Invariant Risk Minimization (IRM). This group of algorithms works under the assumption of multiple environments that represent different interventions in the causal inference context. Those environments are not normally available when working with observational data and real-world applications. Here we propose a method to generate them in an efficient way. We assess the performance of this unsupervised learning problem by implementing ICP on simulated data. We also show how to apply ICP efficiently integrated with our method for causal discovery. Finally, we proposed an improved version of our method in combination with ICP for datasets with multiple covariates where ICP and other causal discovery methods normally degrade in performance.


Constrained Exploration in Reinforcement Learning with Optimality Preservation

arXiv.org Artificial Intelligence

In reinforcement learning, exploration refers to the agent taking actions according to a behavior policy in order to traverse a typically discrete state space and collect rewards. While exploring the state space, the agent uses an update rule to estimate, based on the rewards collected, the Q-values (i.e., state-action values) from one iteration to the next. If the Q-values converge to their optimums, an optimal policy can then be obtained. For a class of reinforcement learning problems, such convergence is guaranteed under the Robbins-Monro conditions [47]. A requirement for satisfying the Robbins-Monro conditions is that every state-action pair must have a non-zero probability of being visited by the agent -- also known as persistent exploration. If we consider the agent taking an action (when it is at a state) as'generating' a symbol denoting that action, the sequences of actions thus generated by the agent as it traverses through the states represent the behavior of the agent. For an episodic learning process, the behavior of the agent consists of all possible action sequences from the initial state to the set of goal states. We refer to such a process as an unconstrained learning process, and the associated optimal Q-values as the intrinsic optimums.


TraInterSim: Adaptive and Planning-Aware Hybrid-Driven Traffic Intersection Simulation

arXiv.org Artificial Intelligence

Traffic intersections are important scenes that can be seen almost everywhere in the traffic system. Currently, most simulation methods perform well at highways and urban traffic networks. In intersection scenarios, the challenge lies in the lack of clearly defined lanes, where agents with various motion plannings converge in the central area from different directions. Traditional model-based methods are difficult to drive agents to move realistically at intersections without enough predefined lanes, while data-driven methods often require a large amount of high-quality input data. Simultaneously, tedious parameter tuning is inevitable involved to obtain the desired simulation results. In this paper, we present a novel adaptive and planning-aware hybrid-driven method (TraInterSim) to simulate traffic intersection scenarios. Our hybrid-driven method combines an optimization-based data-driven scheme with a velocity continuity model. It guides the agent's movements using real-world data and can generate those behaviors not present in the input data. Our optimization method fully considers velocity continuity, desired speed, direction guidance, and planning-aware collision avoidance. Agents can perceive others' motion planning and relative distance to avoid possible collisions. To preserve the individual flexibility of different agents, the parameters in our method are automatically adjusted during the simulation. TraInterSim can generate realistic behaviors of heterogeneous agents in different traffic intersection scenarios in interactive rates. Through extensive experiments as well as user studies, we validate the effectiveness and rationality of the proposed simulation method.


Constructing and deconstructing bias: modeling privilege and mentorship in agent-based simulations

arXiv.org Artificial Intelligence

Bias exists in how we pick leaders, who we perceive as being influential, and who we interact with, not only in society, but in organizational contexts. Drawing from leadership emergence and social influence theories, we investigate potential interventions that support diverse leaders. Using agent-based simulations, we model a collective search process on a fitness landscape. Agents combine individual and social learning, and are represented as a feature vector blending relevant (e.g., individual learning characteristics) and irrelevant (e.g., race or gender) features. Agents use rational principles of learning to estimate feature weights on the basis of performance predictions, which are used to dynamically define social influence in their network. We show how biases arise based on historic privilege, but can be drastically reduced through the use of an intervention (e.g. mentorship). This work provides important insights into the cognitive mechanisms underlying bias construction and deconstruction, while pointing towards real-world interventions to be tested in future empirical work.


Core Challenges in Embodied Vision-Language Planning

arXiv.org Artificial Intelligence

Recent advances in the areas of Multimodal Machine Learning and Artificial Intelligence (AI) have led to the development of challenging tasks at the intersection of Computer Vision, Natural Language Processing, and Robotics. Whereas many approaches and previous survey pursuits have characterised one or two of these dimensions, there has not been a holistic analysis at the center of all three. Moreover, even when combinations of these topics are considered, more focus is placed on describing, e.g., current architectural methods, as opposed to also illustrating high-level challenges and opportunities for the field. In this survey paper, we discuss Embodied Vision-Language Planning (EVLP) tasks, a family of prominent embodied navigation and manipulation problems that jointly leverage computer vision and natural language for interaction in physical environments. We propose a taxonomy to unify these tasks and provide an in-depth analysis and comparison of the current and new algorithmic approaches, metrics, simulators, and datasets used for EVLP tasks. Finally, we present the core challenges that we believe new EVLP works should seek to address, and we advocate for task construction that enables model generalisability and furthers real-world deployment.


A Simple and Effective Method of Cross-Lingual Plagiarism Detection

arXiv.org Artificial Intelligence

We present a simple cross-lingual plagiarism detection method applicable to a large number of languages. The presented approach leverages open multilingual thesauri for candidate retrieval task and pre-trained multilingual BERT-based language models for detailed analysis. The method does not rely on machine translation and word sense disambiguation when in use, and therefore is suitable for a large number of languages, including under-resourced languages. The effectiveness of the proposed approach is demonstrated for several existing and new benchmarks, achieving state-of-the-art results for French, Russian, and Armenian languages.


Towards Explainable AI Writing Assistants for Non-native English Speakers

arXiv.org Artificial Intelligence

We highlight the challenges faced by non-native speakers when using AI writing assistants to paraphrase text. Through an interview study with 15 non-native English speakers (NNESs) with varying levels of English proficiency, we observe that they face difficulties in assessing paraphrased texts generated by AI writing assistants, largely due to the lack of explanations accompanying the suggested paraphrases. Furthermore, we examine their strategies to assess AI-generated texts in the absence of such explanations. Drawing on the needs of NNESs identified in our interview, we propose four potential user interfaces to enhance the writing experience of NNESs using AI writing assistants. The proposed designs focus on incorporating explanations to better support NNESs in understanding and evaluating the AI-generated paraphrasing suggestions.


Council Post: AI Adoption And Reading Habits: How Companies Can Encourage Deep Reading

#artificialintelligence

Your digitally enabled workforce is swimming in communication at every turn. From email, Slack, Jira and back, there is no end to the volume of text and data corporate employees are tasked with reading. Is it any surprise that our reading habits have changed dramatically over the last decade? It turns out the modern workforce tends to skim and skip rather than read deeply for comprehension and introspection. Many digital influences, from our habitual scrolling through social media to the frantic pace of all-day meetings, have trained employees to minimize diligent reading and thorough comprehension practices.


Deep Learning and Reinforcement Learning

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This course introduces you to two of the most sought-after disciplines in Machine Learning: Deep Learning and Reinforcement Learning. Deep Learning is a subset of Machine Learning that has applications in both Supervised and Unsupervised Learning, and is frequently used to power most of the AI applications that we use on a daily basis. First you will learn about the theory behind Neural Networks, which are the basis of Deep Learning, as well as several modern architectures of Deep Learning. Once you have developed a few Deep Learning models, the course will focus on Reinforcement Learning, a type of Machine Learning that has caught up more attention recently. Although currently Reinforcement Learning has only a few practical applications, it is a promising area of research in AI that might become relevant in the near future.


Enzyme Function Prediction from Amino Acid Sequence: How AI is Leading the Way - CBIRT

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An innovative artificial intelligence program called CLEAN (contrastive learning–enabled enzyme annotation) has the ability to predict enzyme activities based on their amino acid sequences, even if the enzymes are unfamiliar or inadequately understood. The researchers have reported that CLEAN has surpassed the most advanced tools in terms of precision, consistency, and sensitivity. However, a deeper understanding of enzymes and their roles would be beneficial in a number of disciplines, including genetics, chemistry, pharmaceuticals, medicine, and industrial materials. The scientists are using the protein language to forecast their performance, similar to how ChatGPT uses written language data to generate predictive phrases. Almost all scientists desire to comprehend the purpose of a protein as soon as they encounter a new protein sequence.