Oceania
LERT: A Linguistically-motivated Pre-trained Language Model
Cui, Yiming, Che, Wanxiang, Wang, Shijin, Liu, Ting
Pre-trained Language Model (PLM) has become a representative foundation model in the natural language processing field. Most PLMs are trained with linguistic-agnostic pre-training tasks on the surface form of the text, such as the masked language model (MLM). To further empower the PLMs with richer linguistic features, in this paper, we aim to propose a simple but effective way to learn linguistic features for pre-trained language models. We propose LERT, a pre-trained language model that is trained on three types of linguistic features along with the original MLM pre-training task, using a linguistically-informed pre-training (LIP) strategy. We carried out extensive experiments on ten Chinese NLU tasks, and the experimental results show that LERT could bring significant improvements over various comparable baselines. Furthermore, we also conduct analytical experiments in various linguistic aspects, and the results prove that the design of LERT is valid and effective. Resources are available at https://github.com/ymcui/LERT
DisentQA: Disentangling Parametric and Contextual Knowledge with Counterfactual Question Answering
Neeman, Ella, Aharoni, Roee, Honovich, Or, Choshen, Leshem, Szpektor, Idan, Abend, Omri
Question answering models commonly have access to two sources of "knowledge" during inference time: (1) parametric knowledge - the factual knowledge encoded in the model weights, and (2) contextual knowledge - external knowledge (e.g., a Wikipedia passage) given to the model to generate a grounded answer. Having these two sources of knowledge entangled together is a core issue for generative QA models as it is unclear whether the answer stems from the given non-parametric knowledge or not. This unclarity has implications on issues of trust, interpretability and factuality. In this work, we propose a new paradigm in which QA models are trained to disentangle the two sources of knowledge. Using counterfactual data augmentation, we introduce a model that predicts two answers for a given question: one based on given contextual knowledge and one based on parametric knowledge. Our experiments on the Natural Questions dataset show that this approach improves the performance of QA models by making them more robust to knowledge conflicts between the two knowledge sources, while generating useful disentangled answers.
EvEntS ReaLM: Event Reasoning of Entity States via Language Models
Spiliopoulou, Evangelia, Pagnoni, Artidoro, Bisk, Yonatan, Hovy, Eduard
This paper investigates models of event implications. Specifically, how well models predict entity state-changes, by targeting their understanding of physical attributes. Nominally, Large Language models (LLM) have been exposed to procedural knowledge about how objects interact, yet our benchmarking shows they fail to reason about the world. Conversely, we also demonstrate that existing approaches often misrepresent the surprising abilities of LLMs via improper task encodings and that proper model prompting can dramatically improve performance of reported baseline results across multiple tasks. In particular, our results indicate that our prompting technique is especially useful for unseen attributes (out-of-domain) or when only limited data is available.
Assistive Completion of Agrammatic Aphasic Sentences: A Transfer Learning Approach using Neurolinguistics-based Synthetic Dataset
Misra, Rohit, Mishra, Sapna S, Gandhi, Tapan K.
Damage to the inferior frontal gyrus (Broca's area) can cause agrammatic aphasia wherein patients, although able to comprehend, lack the ability to form complete sentences. This inability leads to communication gaps which cause difficulties in their daily lives. The usage of assistive devices can help in mitigating these issues and enable the patients to communicate effectively. However, due to lack of large scale studies of linguistic deficits in aphasia, research on such assistive technology is relatively limited. In this work, we present two contributions that aim to re-initiate research and development in this field. Firstly, we propose a model that uses linguistic features from small scale studies on aphasia patients and generates large scale datasets of synthetic aphasic utterances from grammatically correct datasets. We show that the mean length of utterance, the noun/verb ratio, and the simple/complex sentence ratio of our synthetic datasets correspond to the reported features of aphasic speech. Further, we demonstrate how the synthetic datasets may be utilized to develop assistive devices for aphasia patients. The pre-trained T5 transformer is fine-tuned using the generated dataset to suggest 5 corrected sentences given an aphasic utterance as input. We evaluate the efficacy of the T5 model using the BLEU and cosine semantic similarity scores. Affirming results with BLEU score of 0.827/1.00 and semantic similarity of 0.904/1.00 were obtained. These results provide a strong foundation for the concept that a synthetic dataset based on small scale studies on aphasia can be used to develop effective assistive technology.
Where to start? Analyzing the potential value of intermediate models
Choshen, Leshem, Venezian, Elad, Don-Yehia, Shachar, Slonim, Noam, Katz, Yoav
Previous studies observed that finetuned models may be better base models than the vanilla pretrained model. Such a model, finetuned on some source dataset, may provide a better starting point for a new finetuning process on a desired target dataset. Here, we perform a systematic analysis of this intertraining scheme, over a wide range of English classification tasks. Surprisingly, our analysis suggests that the potential intertraining gain can be analyzed independently for the target dataset under consideration, and for a base model being considered as a starting point. This is in contrast to current perception that the alignment between the target dataset and the source dataset used to generate the base model is a major factor in determining intertraining success. We analyze different aspects that contribute to each. Furthermore, we leverage our analysis to propose a practical and efficient approach to determine if and how to select a base model in real-world settings. Last, we release an updating ranking of best models in the HuggingFace hub per architecture https://ibm.github.io/model-recycling/.
Processing Long Legal Documents with Pre-trained Transformers: Modding LegalBERT and Longformer
Mamakas, Dimitris, Tsotsi, Petros, Androutsopoulos, Ion, Chalkidis, Ilias
Pre-trained Transformers currently dominate most NLP tasks. They impose, however, limits on the maximum input length (512 sub-words in BERT), which are too restrictive in the legal domain. Even sparse-attention models, such as Longformer and BigBird, which increase the maximum input length to 4,096 sub-words, severely truncate texts in three of the six datasets of LexGLUE. Simpler linear classifiers with TF-IDF features can handle texts of any length, require far less resources to train and deploy, but are usually outperformed by pre-trained Transformers. We explore two directions to cope with long legal texts: (i) modifying a Longformer warm-started from LegalBERT to handle even longer texts (up to 8,192 sub-words), and (ii) modifying LegalBERT to use TF-IDF representations. The first approach is the best in terms of performance, surpassing a hierarchical version of LegalBERT, which was the previous state of the art in LexGLUE. The second approach leads to computationally more efficient models at the expense of lower performance, but the resulting models still outperform overall a linear SVM with TF-IDF features in long legal document classification.
Truncated proposals for scalable and hassle-free simulation-based inference
Deistler, Michael, Goncalves, Pedro J, Macke, Jakob H
Simulation-based inference (SBI) solves statistical inverse problems by repeatedly running a stochastic simulator and inferring posterior distributions from model-simulations. To improve simulation efficiency, several inference methods take a sequential approach and iteratively adapt the proposal distributions from which model simulations are generated. However, many of these sequential methods are difficult to use in practice, both because the resulting optimisation problems can be challenging and efficient diagnostic tools are lacking. To overcome these issues, we present Truncated Sequential Neural Posterior Estimation (TSNPE). TSNPE performs sequential inference with truncated proposals, sidestepping the optimisation issues of alternative approaches. In addition, TSNPE allows to efficiently perform coverage tests that can scale to complex models with many parameters. We demonstrate that TSNPE performs on par with previous methods on established benchmark tasks. We then apply TSNPE to two challenging problems from neuroscience and show that TSNPE can successfully obtain the posterior distributions, whereas previous methods fail. Overall, our results demonstrate that TSNPE is an efficient, accurate, and robust inference method that can scale to challenging scientific models.
Leveraging Fully Observable Policies for Learning under Partial Observability
Nguyen, Hai, Baisero, Andrea, Wang, Dian, Amato, Christopher, Platt, Robert
In contrast, the setting of fully observable (FO) control has featured the success of many powerful reinforcement learning (RL) algorithms (e.g., [8, 9, 10, 11]). Unfortunately, full observability only holds for a small portion of realistic robotics problems. Figure 1: To reach the In this work, we attempt to leverage good fully observable policies (state correct goal object, a experts) available only during offline training to help train PO policies state expert takes the that can execute online. We rely on the setting of offline training and red path directly, while online execution, a successful RL framework where an agent can use a partially observable "privileged" information such as the state [12, 13, 14, 15] or the belief agent must first take the about the state [6] during offline training, e.g., from simulators, to efficiently green path to identify learn PO policies that are later can be deployed without the access the correct goal object, to the privileged information anymore. In this work, the privileged information then take the red path. is not just the state itself but also the state expert. Our setting can be illustrated in a navigation task (Figure 1), which requires an agent to navigate to an unknown goal object on the right, identifiable by an object on the left side. While the optimal behavior under partial observability is to first navigate leftwards to identify the goal object, the state expert is able to move to the goal object directly. Despite being sup-optimal from the PO perspective, the state expert can provide experience during training leading to the goal object, which is potentially useful for both exploration and as a part of the policy needed in the PO case after the goal object is identified.
Sensore And Lithgold To Pursue Gecko North Lithium
SensOre (ASX:S3N) aims to become the top performing global minerals targeting company through deployment of big data, artificial intelligence (AI)/machine learning technologies and geoscience expertise. Richard Taylor, CEO, SensOre Ltd said"The Gecko North Project demonstrates the combination of AI target generation and conventional exploration techniques coming together to fast-track target development. It demonstrates our novel approach to project generation bringing together international funding for battery minerals with world class exploration expertise with our partners in LithGold. Importantly, this approach gives SensOre shareholders the opportunity to benefit from the technology with exposure to any major discovery." Kevin Schultz, Executive Chairman, LithGold Minerals said"The agreement allows LithGold to partner with an exciting mining technology group and to focus on our portfolio of projects while retaining the precious metal rights over the Gecko North Project which first attracted us to the area. We look forward to seeing the lithium potential of the area developed further."
Female octopuses are caught on video launching shells at males attempting to mate with them
Female octopuses have been caught on video launching shells at males attempting to mate with them. Scientists at the University of Sydney recorded gloomy octopuses, or Octopus tetricus, in Jervis Bay in Australia with underwater cameras. They watched them repeatedly throw marine debris using their siphon - a tube-shaped structure that can draw water in an out of its body. As they have to move their siphon to an unusual position to do this, it is assumed to be a deliberate manoeuvre. Throws were performed by both sexes, but it was female octopuses 66 per cent of the time, and sometimes occurred during mating attempts.