Angular Gap: Reducing the Uncertainty of Image Difficulty through Model Calibration
Curriculum learning needs example difficulty to proceed from easy to hard. However, the credibility of image difficulty is rarely investigated, which can seriously affect the effectiveness of curricula. In this work, we propose Angular Gap, a measure of difficulty based on the difference in angular distance between feature embeddings and class-weight embeddings built by hyperspherical learning. To ascertain difficulty estimation, we introduce class-wise model calibration, as a post-training technique, to the learnt hyperbolic space. This bridges the gap between probabilistic model calibration and angular distance estimation of hyperspherical learning. We show the superiority of our calibrated Angular Gap over recent difficulty metrics on CIFAR10-H and ImageNetV2. We further propose Angular Gap based curriculum learning for unsupervised domain adaptation that can translate from learning easy samples to mining hard samples. We combine this curriculum with a state-of-the-art self-training method, Cycle Self Training (CST). The proposed Curricular CST learns robust representations and outperforms recent baselines on Office31 and VisDA 2017.
Code (1)
Tasks
Domain AdaptationUnsupervised Domain AdaptationSimilar Papers 제목 키워드 기반
Policy-Conditioned Uncertainty Sets for Robust Markov Decision Processes
What policy should be employed in a Markov decision process with uncertain parameters? Robust optimization answer to this question is to use rectangular uncertainty sets, which independently reflect available knowledge a…
Transfer LearningTowards Theoretical Understandings of Robust Markov Decision Processes: Sample Complexity and Asymptotics
In this paper, we study the non-asymptotic and asymptotic performances of the optimal robust policy and value function of robust Markov Decision Processes(MDPs), where the optimal robust policy and value function are sol…
Policy Gradient Algorithms for Robust MDPs with Non-Rectangular Uncertainty Sets
We propose policy gradient algorithms for robust infinite-horizon Markov decision processes (MDPs) with non-rectangular uncertainty sets, thereby addressing an open challenge in the robust MDP literature. Indeed, uncerta…
Towards the Application of Calibrated Transformers to the Unsupervised Estimation of Question Difficulty from Text
Being able to accurately perform Question Difficulty Estimation (QDE) can improve the accuracy of students’ assessment and better their learning experience. Traditional approaches to QDE are either subjective or introduc…
Question AnsweringRoping in Uncertainty: Robustness and Regularization in Markov Games
We study robust Markov games (RMG) with $s$-rectangular uncertainty. We show a general equivalence between computing a robust Nash equilibrium (RNE) of a $s$-rectangular RMG and computing a Nash equilibrium (NE) of an ap…