Goto

Collaborating Authors

 cvg


Error-quantified Conformal Inference for Time Series

Wu, Junxi, Hu, Dongjian, Bao, Yajie, Xia, Shu-Tao, Zou, Changliang

arXiv.org Machine Learning

Uncertainty quantification in time series prediction is challenging due to the temporal dependence and distribution shift on sequential data. Conformal inference provides a pivotal and flexible instrument for assessing the uncertainty of machine learning models through prediction sets. Recently, a series of online conformal inference methods updated thresholds of prediction sets by performing online gradient descent on a sequence of quantile loss functions. A drawback of such methods is that they only use the information of revealed non-conformity scores via miscoverage indicators but ignore error quantification, namely the distance between the non-conformity score and the current threshold. To accurately leverage the dynamic of miscoverage error, we propose Error-quantified Conformal Inference (ECI) by smoothing the quantile loss function. ECI introduces a continuous and adaptive feedback scale with the miscoverage error, rather than simple binary feedback in existing methods. We establish a long-term coverage guarantee for ECI under arbitrary dependence and distribution shift. The extensive experimental results show that ECI can achieve valid miscoverage control and output tighter prediction sets than other baselines. Uncertainty quantification for time series is crucial across various domains including finance, climate science, epidemiology, energy, supply chains, and macroeconomics, etc, especially in highstakes areas.


Data Distribution Bottlenecks in Grounding Language Models to Knowledge Bases

Shu, Yiheng, Yu, Zhiwei

arXiv.org Artificial Intelligence

Language models (LMs) have already demonstrated remarkable abilities in understanding and generating both natural and formal language. Despite these advances, their integration with real-world environments such as large-scale knowledge bases (KBs) remains an underdeveloped area, affecting applications such as semantic parsing and indulging in "hallucinated" information. This paper is an experimental investigation aimed at uncovering the robustness challenges that LMs encounter when tasked with knowledge base question answering (KBQA). The investigation covers scenarios with inconsistent data distribution between training and inference, such as generalization to unseen domains, adaptation to various language variations, and transferability across different datasets. Our comprehensive experiments reveal that even when employed with our proposed data augmentation techniques, advanced small and large language models exhibit poor performance in various dimensions. While the LM is a promising technology, the robustness of the current form in dealing with complex environments is fragile and of limited practicality because of the data distribution issue. This calls for future research on data collection and LM learning paradims.


Conformal PID Control for Time Series Prediction

Angelopoulos, Anastasios N., Candes, Emmanuel J., Tibshirani, Ryan J.

arXiv.org Artificial Intelligence

We study the problem of uncertainty quantification for time series prediction, with the goal of providing easy-to-use algorithms with formal guarantees. The algorithms we present build upon ideas from conformal prediction and control theory, are able to prospectively model conformal scores in an online setting, and adapt to the presence of systematic errors due to seasonality, trends, and general distribution shifts. Our theory both simplifies and strengthens existing analyses in online conformal prediction. Experiments on 4-week-ahead forecasting of statewide COVID-19 death counts in the U.S. show an improvement in coverage over the ensemble forecaster used in official CDC communications. We also run experiments on predicting electricity demand, market returns, and temperature using autoregressive, Theta, Prophet, and Transformer models. We provide an extendable codebase for testing our methods and for the integration of new algorithms, data sets, and forecasting rules.


Enhanced Airport Passenger Experience with TaskWatch and AWS Panorama

#artificialintelligence

The Cincinnati/Northern Kentucky International Airport (CVG) is expanding its long-standing relationship with TaskWatch to help automate manual processes and gain insight into its complex operations. Adding TaskWatch's computer vision platform that works in conjunction with AWS Panorama, the Airport sees, adds, and explores distinct use cases for advanced artificial intelligence (AI). TaskWatch is leading the way for continuous improvement in capacity management and productivity, which are vital contributors to the overall customer experience. Brian Cobb, CIO at CVG, explains: "CVG Airport is committed to providing a world-class traveler experience through continuous innovation and strategic partnerships. Using TaskWatch's application on AWS Panorama, we can bring computer vision to our existing IP cameras to automatically monitor congestion for over 70,000 square feet of airport traffic lanes.


Understanding Deep Architectures with Reasoning Layer

Chen, Xinshi, Zhang, Yufei, Reisinger, Christoph, Song, Le

arXiv.org Machine Learning

Recently, there has been a surge of interest in combining deep learning models with reasoning in order to handle more sophisticated learning tasks. In many cases, a reasoning task can be solved by an iterative algorithm. This algorithm is often unrolled, and used as a specialized layer in the deep architecture, which can be trained end-to-end with other neural components. Although such hybrid deep architectures have led to many empirical successes, the theoretical foundation of such architectures, especially the interplay between algorithm layers and other neural layers, remains largely unexplored. In this paper, we take an initial step towards an understanding of such hybrid deep architectures by showing that properties of the algorithm layers, such as convergence, stability, and sensitivity, are intimately related to the approximation and generalization abilities of the end-to-end model. Furthermore, our analysis matches closely our experimental observations under various conditions, suggesting that our theory can provide useful guidelines for designing deep architectures with reasoning layers.