Education
Ivy League university unveils plan to teach students with AI chatbot this fall: 'Evolution' of 'tradition'
PactumAI co-founder and CEO Martin Rand explains how workers can use artificial intelligence to enhance their careers and positions. Students at one of the America's most elite universities will be in for a surprise this fall when they discover their flagship coding class is taught with help from an A.I. chatbot in a bend on what Professor David Malan, the course's overseer, defines as an "evolution" of "tradition." Harvard University unleashed plans to incorporate A.I. chatbots to teach the course, venturing deeper into the uncharted territory of artificial intelligence - a territory that has exponentially grown and altered the course of technology in the past several months. Though the idea sounds novel and exciting, Martin Rand, PactumAI co-founder and CEO, warned to be wary of the "dangers." I INTERVIEWED CHATGPT AS IF IT WAS A HUMAN; HERE'S WHAT IT HAD TO SAY THAT GAVE ME CHILLS People walk through the gate on Harvard Yard at the Harvard University campus on June 29, 2023 in Cambridge, Massachusetts.
Continual Learning Beyond a Single Model
Doan, Thang, Mirzadeh, Seyed Iman, Farajtabar, Mehrdad
A growing body of research in continual learning focuses on the catastrophic forgetting problem. While many attempts have been made to alleviate this problem, the majority of the methods assume a single model in the continual learning setup. In this work, we question this assumption and show that employing ensemble models can be a simple yet effective method to improve continual performance. However, ensembles' training and inference costs can increase significantly as the number of models grows. Motivated by this limitation, we study different ensemble models to understand their benefits and drawbacks in continual learning scenarios. Finally, to overcome the high compute cost of ensembles, we leverage recent advances in neural network subspace to propose a computationally cheap algorithm with similar runtime to a single model yet enjoying the performance benefits of ensembles. Continual learning (CL) and Lifelong learning (Thrun, 1994) have recently gained popularity since many real-world applications fall into that setting. It describes the scenario where not only a stream of data arrives sequentially, but their distribution also changes over time. This setup induces Catastrophic Forgetting (CF) (McCloskey & Cohen, 1989) which is a degradation of performances on previous data due to distribution shift between tasks (Doan et al., 2021). One fundamental goal in continual learning is to learn from the new incoming tasks while retaining knowledge from the past and avoiding interference that can lead to poor performance (Lesort et al., 2021). This becomes particularly challenging when the stream of data increases because all the burden is left to a single model. A simple yet effective solution is to rely on an ensemble method that improves performance over a single model. Inspired by bootstrapping (Breiman, 1996), deep ensembles initialize and train multiple neural networks independently (Lakshminarayanan et al., 2017; Fort et al., 2019).
Doubly Robust Estimation of Direct and Indirect Quantile Treatment Effects with Machine Learning
Hsu, Yu-Chin, Huber, Martin, Yen, Yu-Min
We suggest double/debiased machine learning estimators of direct and indirect quantile treatment effects under a selection-on-observables assumption. This permits disentangling the causal effect of a binary treatment at a specific outcome rank into an indirect component that operates through an intermediate variable called mediator and an (unmediated) direct impact. The proposed method is based on the efficient score functions of the cumulative distribution functions of potential outcomes, which are robust to certain misspecifications of the nuisance parameters, i.e., the outcome, treatment, and mediator models. We estimate these nuisance parameters by machine learning and use cross-fitting to reduce overfitting bias in the estimation of direct and indirect quantile treatment effects. We establish uniform consistency and asymptotic normality of our effect estimators. We also propose a multiplier bootstrap for statistical inference and show the validity of the multiplier bootstrap. Finally, we investigate the finite sample performance of our method in a simulation study and apply it to empirical data from the National Job Corp Study to assess the direct and indirect earnings effects of training.
A Comprehensive Survey of Artificial Intelligence Techniques for Talent Analytics
Qin, Chuan, Zhang, Le, Zha, Rui, Shen, Dazhong, Zhang, Qi, Sun, Ying, Zhu, Chen, Zhu, Hengshu, Xiong, Hui
In today's competitive and fast-evolving business environment, it is a critical time for organizations to rethink how to make talent-related decisions in a quantitative manner. Indeed, the recent development of Big Data and Artificial Intelligence (AI) techniques have revolutionized human resource management. The availability of large-scale talent and management-related data provides unparalleled opportunities for business leaders to comprehend organizational behaviors and gain tangible knowledge from a data science perspective, which in turn delivers intelligence for real-time decision-making and effective talent management at work for their organizations. In the last decade, talent analytics has emerged as a promising field in applied data science for human resource management, garnering significant attention from AI communities and inspiring numerous research efforts. To this end, we present an up-to-date and comprehensive survey on AI technologies used for talent analytics in the field of human resource management. Specifically, we first provide the background knowledge of talent analytics and categorize various pertinent data. Subsequently, we offer a comprehensive taxonomy of relevant research efforts, categorized based on three distinct application-driven scenarios: talent management, organization management, and labor market analysis. In conclusion, we summarize the open challenges and potential prospects for future research directions in the domain of AI-driven talent analytics.
A Double Machine Learning Approach to Combining Experimental and Observational Data
Morucci, Marco, Orlandi, Vittorio, Parikh, Harsh, Roy, Sudeepa, Rudin, Cynthia, Volfovsky, Alexander
Experimental and observational studies often lack validity due to untestable assumptions. We propose a double machine learning approach to combine experimental and observational studies, allowing practitioners to test for assumption violations and estimate treatment effects consistently. Our framework tests for violations of external validity and ignorability under milder assumptions. When only one assumption is violated, we provide semi-parametrically efficient treatment effect estimators. However, our no-free-lunch theorem highlights the necessity of accurately identifying the violated assumption for consistent treatment effect estimation. We demonstrate the applicability of our approach in three real-world case studies, highlighting its relevance for practical settings.
On Conditional and Compositional Language Model Differentiable Prompting
Pilault, Jonathan, Liu, Can, Bansal, Mohit, Dreyer, Markus
Prompts have been shown to be an effective method to adapt a frozen Pretrained Language Model (PLM) to perform well on downstream tasks. Prompts can be represented by a human-engineered word sequence or by a learned continuous embedding. In this work, we investigate conditional and compositional differentiable prompting. We propose a new model, Prompt Production System (PRopS), which learns to transform task instructions or input metadata, into continuous prompts that elicit task-specific outputs from the PLM. Our model uses a modular network structure based on our neural formulation of Production Systems, which allows the model to learn discrete rules -- neural functions that learn to specialize in transforming particular prompt input patterns, making it suitable for compositional transfer learning and few-shot learning. We present extensive empirical and theoretical analysis and show that PRopS consistently surpasses other PLM adaptation techniques, and often improves upon fully fine-tuned models, on compositional generalization tasks, controllable summarization and multilingual translation, while needing fewer trainable parameters.
Learning to Branch in Combinatorial Optimization with Graph Pointer Networks
Wang, Rui, Zhou, Zhiming, Zhang, Tao, Wang, Ling, Xu, Xin, Liao, Xiangke, Li, Kaiwen
Branch-and-bound is a typical way to solve combinatorial optimization problems. This paper proposes a graph pointer network model for learning the variable selection policy in the branch-and-bound. We extract the graph features, global features and historical features to represent the solver state. The proposed model, which combines the graph neural network and the pointer mechanism, can effectively map from the solver state to the branching variable decisions. The model is trained to imitate the classic strong branching expert rule by a designed top-k Kullback-Leibler divergence loss function. Experiments on a series of benchmark problems demonstrate that the proposed approach significantly outperforms the widely used expert-designed branching rules. Our approach also outperforms the state-of-the-art machine-learning-based branch-and-bound methods in terms of solving speed and search tree size on all the test instances. In addition, the model can generalize to unseen instances and scale to larger instances.
Evaluation of medium-large Language Models at zero-shot closed book generative question answering
Large language models (LLMs) have garnered significant attention, but the definition of "large" lacks clarity. This paper focuses on medium-sized language models (MLMs), defined as having at least six billion parameters but less than 100 billion. The study evaluates MLMs regarding zero-shot generative question answering, which requires models to provide elaborate answers without external document retrieval. The paper introduces an own test dataset and presents results from human evaluation. Results show that combining the best answers from different MLMs yielded an overall correct answer rate of 82.7% which is better than the 60.9% of ChatGPT. The best MLM achieved 71.8% and has 33B parameters, which highlights the importance of using appropriate training data for fine-tuning rather than solely relying on the number of parameters. More fine-grained feedback should be used to further improve the quality of answers. The open source community is quickly closing the gap to the best commercial models.
EmbedDistill: A Geometric Knowledge Distillation for Information Retrieval
Kim, Seungyeon, Rawat, Ankit Singh, Zaheer, Manzil, Jayasumana, Sadeep, Sadhanala, Veeranjaneyulu, Jitkrittum, Wittawat, Menon, Aditya Krishna, Fergus, Rob, Kumar, Sanjiv
Large neural models (such as Transformers) achieve state-of-the-art performance for information retrieval (IR). In this paper, we aim to improve distillation methods that pave the way for the resource-efficient deployment of such models in practice. Inspired by our theoretical analysis of the teacher-student generalization gap for IR models, we propose a novel distillation approach that leverages the relative geometry among queries and documents learned by the large teacher model. Unlike existing teacher score-based distillation methods, our proposed approach employs embedding matching tasks to provide a stronger signal to align the representations of the teacher and student models. In addition, it utilizes query generation to explore the data manifold to reduce the discrepancies between the student and the teacher where training data is sparse. Furthermore, our analysis also motivates novel asymmetric architectures for student models which realizes better embedding alignment without increasing online inference cost. On standard benchmarks like MSMARCO, we show that our approach successfully distills from both dual-encoder (DE) and cross-encoder (CE) teacher models to 1/10th size asymmetric students that can retain 95-97% of the teacher performance.
Online nearest neighbor classification
We study an instance of online non-parametric classification in the realizable setting. In particular, we consider the classical 1-nearest neighbor algorithm, and show that it achieves sublinear regret - that is, a vanishing mistake rate - against dominated or smoothed adversaries in the realizable setting.