Oceania
Learning Perturbations to Explain Time Series Predictions
Explaining predictions based on multivariate time series data carries the additional difficulty of handling not only multiple features, but also time dependencies. It matters not only what happened, but also when, and the same feature could have a very different impact on a prediction depending on this time information. Previous work has used perturbation-based saliency methods to tackle this issue, perturbing an input using a trainable mask to discover which features at which times are driving the predictions. However these methods introduce fixed perturbations, inspired from similar methods on static data, while there seems to be little motivation to do so on temporal data. In this work, we aim to explain predictions by learning not only masks, but also associated perturbations. We empirically show that learning these perturbations significantly improves the quality of these explanations on time series data.
Shapley Based Residual Decomposition for Instance Analysis
In this paper, we introduce the idea of decomposing the residuals of regression with respect to the data instances instead of features. This allows us to determine the effects of each individual instance on the model and each other, and in doing so makes for a model-agnostic method of identifying instances of interest. In doing so, we can also determine the appropriateness of the model and data in the wider context of a given study. The paper focuses on the possible applications that such a framework brings to the relatively unexplored field of instance analysis in the context of Explainable AI tasks.
The Alternating-Time \mu-Calculus With Disjunctive Explicit Strategies
Humml, Merlin, Schröder, Lutz, Pattinson, Dirk
Alternating-time temporal logic (ATL) and its extensions, including the alternating-time $\mu$-calculus (AMC), serve the specification of the strategic abilities of coalitions of agents in concurrent game structures. The key ingredient of the logic are path quantifiers specifying that some coalition of agents has a joint strategy to enforce a given goal. This basic setup has been extended to let some of the agents (revocably) commit to using certain named strategies, as in ATL with explicit strategies (ATLES). In the present work, we extend ATLES with fixpoint operators and strategy disjunction, arriving at the alternating-time $\mu$-calculus with disjunctive explicit strategies (AMCDES), which allows for a more flexible formulation of temporal properties (e.g. fairness) and, through strategy disjunction, a form of controlled nondeterminism in commitments. Our main result is an ExpTime upper bound for satisfiability checking (which is thus ExpTime-complete). We also prove upper bounds QP (quasipolynomial time) and NP $\cap$ coNP for model checking under fixed interpretations of explicit strategies, and NP under open interpretation. Our key technical tool is a treatment of the AMCDES within the generic framework of coalgebraic logic, which in particular reduces the analysis of most reasoning tasks to the treatment of a very simple one-step logic featuring only propositional operators and next-step operators without nesting; we give a new model construction principle for this one-step logic that relies on a set-valued variant of first-order resolution.
Adapting Multi-Lingual ASR Models for Handling Multiple Talkers
Li, Chenda, Qian, Yao, Chen, Zhuo, Kanda, Naoyuki, Wang, Dongmei, Yoshioka, Takuya, Qian, Yanmin, Zeng, Michael
State-of-the-art large-scale universal speech models (USMs) show a decent automatic speech recognition (ASR) performance across multiple domains and languages. However, it remains a challenge for these models to recognize overlapped speech, which is often seen in meeting conversations. We propose an approach to adapt USMs for multi-talker ASR. We first develop an enhanced version of serialized output training to jointly perform multi-talker ASR and utterance timestamp prediction. That is, we predict the ASR hypotheses for all speakers, count the speakers, and estimate the utterance timestamps at the same time. We further introduce a lightweight adapter module to maintain the multilingual property of the USMs even when we perform the adaptation with only a single language. Experimental results obtained using the AMI and AliMeeting corpora show that our proposed approach effectively transfers the USMs to a strong multilingual multi-talker ASR model with timestamp prediction capability.
Rethinking Annotation: Can Language Learners Contribute?
Yoo, Haneul, Putri, Rifki Afina, Lee, Changyoon, Lee, Youngin, Ahn, So-Yeon, Kang, Dongyeop, Oh, Alice
Researchers have traditionally recruited native speakers to provide annotations for widely used benchmark datasets. However, there are languages for which recruiting native speakers can be difficult, and it would help to find learners of those languages to annotate the data. In this paper, we investigate whether language learners can contribute annotations to benchmark datasets. In a carefully controlled annotation experiment, we recruit 36 language learners, provide two types of additional resources (dictionaries and machine-translated sentences), and perform mini-tests to measure their language proficiency. We target three languages, English, Korean, and Indonesian, and the four NLP tasks of sentiment analysis, natural language inference, named entity recognition, and machine reading comprehension. We find that language learners, especially those with intermediate or advanced levels of language proficiency, are able to provide fairly accurate labels with the help of additional resources. Moreover, we show that data annotation improves learners' language proficiency in terms of vocabulary and grammar. One implication of our findings is that broadening the annotation task to include language learners can open up the opportunity to build benchmark datasets for languages for which it is difficult to recruit native speakers.
Repairing the Cracked Foundation: A Survey of Obstacles in Evaluation Practices for Generated Text
Gehrmann, Sebastian (a:1:{s:5:"en_US";s:15:"Google Research";}) | Clark, Elizabeth (Google Research) | Sellam, Thibault
Evaluation practices in natural language generation (NLG) have many known flaws, but improved evaluation approaches are rarely widely adopted. This issue has become more urgent, since neural generation models have improved to the point where their outputs can often no longer be distinguished based on the surface-level features that older metrics rely on. This paper surveys the issues with human and automatic model evaluations and with commonly used datasets in NLG that have been pointed out over the past 20 years. We summarize, categorize, and discuss how researchers have been addressing these issues and what their findings mean for the current state of model evaluations. Building on those insights, we lay out a long-term vision for evaluation research and propose concrete steps for researchers to improve their evaluation processes. Finally, we analyze 66 generation papers from recent NLP conferences in how well they already follow these suggestions and identify which areas require more drastic changes to the status quo.
Improving Confidence in Evolutionary Mine Scheduling via Uncertainty Discounting
Stimson, Michael, Reid, William, Neumann, Aneta, Ratcliffe, Simon, Neumann, Frank
Long-term planning and production scheduling are among the most critical tasks in the area of mining. The goal is to extract valuable ore from an orebody in a sequence that takes into account many mining and precedence constraints in a way that is economically efficient [1]. This is an important real-world optimisation problem that has been studied in the literature over many years. This includes mixed integer programming approaches based on block scheduling [2, 3]. Each block in a block model (a discretised spatial approximation of the mineral deposit) has a given estimated value based on the metal grade and the excavation cost. Other heuristic techniques include dealing with specific characteristics such as uncertainties of the problem [4-6]. Different software products that offer a variety of approaches for mine planning and extraction sequences are available [7, 8]. Evolutionary computation techniques have successfully been applied in the area of mining, in particular to large scale optimisation problems such as the cost efficient extraction of ore [9, 10], the ore processing and blending problem [11-15], and the large-scale open pit mine scheduling problem [16, 17]. Particle swarm algorithms were utilised to solve the capacity constrained open pit mining problem [18] and the transportation and layout problem of locating a crushing station in an open-pit mine [19].
QAMPARI: An Open-domain Question Answering Benchmark for Questions with Many Answers from Multiple Paragraphs
Amouyal, Samuel Joseph, Wolfson, Tomer, Rubin, Ohad, Yoran, Ori, Herzig, Jonathan, Berant, Jonathan
Existing benchmarks for open-domain question answering (ODQA) typically focus on questions whose answers can be extracted from a single paragraph. By contrast, many natural questions, such as "What players were drafted by the Brooklyn Nets?" have a list of answers. Answering such questions requires retrieving and reading from many passages, in a large corpus. We introduce QAMPARI, an ODQA benchmark, where question answers are lists of entities, spread across many paragraphs. We created QAMPARI by (a) generating questions with multiple answers from Wikipedia's knowledge graph and tables, (b) automatically pairing answers with supporting evidence in Wikipedia paragraphs, and (c) manually paraphrasing questions and validating each answer. We train ODQA models from the retrieve-and-read family and find that QAMPARI is challenging in terms of both passage retrieval and answer generation, reaching an F1 score of 32.8 at best. Our results highlight the need for developing ODQA models that handle a broad range of question types, including single and multi-answer questions.
Exploring Effectiveness of GPT-3 in Grammatical Error Correction: A Study on Performance and Controllability in Prompt-Based Methods
Loem, Mengsay, Kaneko, Masahiro, Takase, Sho, Okazaki, Naoaki
Large-scale pre-trained language models such as GPT-3 have shown remarkable performance across various natural language processing tasks. However, applying prompt-based methods with GPT-3 for Grammatical Error Correction (GEC) tasks and their controllability remains underexplored. Controllability in GEC is crucial for real-world applications, particularly in educational settings, where the ability to tailor feedback according to learner levels and specific error types can significantly enhance the learning process. This paper investigates the performance and controllability of prompt-based methods with GPT-3 for GEC tasks using zero-shot and few-shot setting. We explore the impact of task instructions and examples on GPT-3's output, focusing on controlling aspects such as minimal edits, fluency edits, and learner levels. Our findings demonstrate that GPT-3 could effectively perform GEC tasks, outperforming existing supervised and unsupervised approaches. We also showed that GPT-3 could achieve controllability when appropriate task instructions and examples are given.
PaLI-X: On Scaling up a Multilingual Vision and Language Model
Chen, Xi, Djolonga, Josip, Padlewski, Piotr, Mustafa, Basil, Changpinyo, Soravit, Wu, Jialin, Ruiz, Carlos Riquelme, Goodman, Sebastian, Wang, Xiao, Tay, Yi, Shakeri, Siamak, Dehghani, Mostafa, Salz, Daniel, Lucic, Mario, Tschannen, Michael, Nagrani, Arsha, Hu, Hexiang, Joshi, Mandar, Pang, Bo, Montgomery, Ceslee, Pietrzyk, Paulina, Ritter, Marvin, Piergiovanni, AJ, Minderer, Matthias, Pavetic, Filip, Waters, Austin, Li, Gang, Alabdulmohsin, Ibrahim, Beyer, Lucas, Amelot, Julien, Lee, Kenton, Steiner, Andreas Peter, Li, Yang, Keysers, Daniel, Arnab, Anurag, Xu, Yuanzhong, Rong, Keran, Kolesnikov, Alexander, Seyedhosseini, Mojtaba, Angelova, Anelia, Zhai, Xiaohua, Houlsby, Neil, Soricut, Radu
We present the training recipe and results of scaling up PaLI-X, a multilingual vision and language model, both in terms of size of the components and the breadth of its training task mixture. Our model achieves new levels of performance on a wide-range of varied and complex tasks, including multiple image-based captioning and question-answering tasks, image-based document understanding and few-shot (in-context) learning, as well as object detection, video question answering, and video captioning. PaLI-X advances the state-of-the-art on most vision-and-language benchmarks considered (25+ of them). Finally, we observe emerging capabilities, such as complex counting and multilingual object detection, tasks that are not explicitly in the training mix.