The widespread of offensive content online, such as hate speech and cyber-bullying, is a global phenomenon. This has sparked interest in the artificial intelligence (AI) and natural language processing (NLP) communities, motivating the development of various systems trained to detect potentially harmful content automatically. These systems require annotated datasets to train the machine learning (ML) models. However, with a few notable exceptions, most datasets on this topic have dealt with English and a few other high-resource languages. As a result, the research in offensive language identification has been limited to these languages. This paper addresses this gap by tackling offensive language identification in Sinhala, a low-resource Indo-Aryan language spoken by over 17 million people in Sri Lanka. We introduce the Sinhala Offensive Language Dataset (SOLD) and present multiple experiments on this dataset. SOLD is a manually annotated dataset containing 10,000 posts from Twitter annotated as offensive and not offensive at both sentence-level and token-level, improving the explainability of the ML models. SOLD is the first large publicly available offensive language dataset compiled for Sinhala. We also introduce SemiSOLD, a larger dataset containing more than 145,000 Sinhala tweets, annotated following a semi-supervised approach.
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多词表达式(MWE)是一系列单词,共同提出的含义不是从其单个单词中得出的。处理MWE的任务在许多自然语言处理(NLP)应用中至关重要,包括机器翻译和术语提取。因此,在不同领域中检测MWE是一个重要的研究主题。在本文中,我们探索了最新的神经变压器,以检测花和植物名称中的MWES。我们在由植物和花朵百科全书创建的数据集上评估了不同的变压器模型。我们从经验上表明,Transformer模型模型优于基于长期记忆(LSTM)的先前神经模型。
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多字表达式(MWES)呈现单词组,其中整体的含义不是源于其部分的含义。处理MWE的任务在许多自然语言处理(NLP)应用中至关重要,包括机器翻译和术语提取。因此,检测MWE是一个流行的研究主题。在本文中,我们在检测MWES的任务中探索了最新的神经变压器。我们在数据集中凭经验评估了Semeval-2016任务10:检测最小的语义单元及其含义(DIMSUM)。我们表明,变压器模型的表现优于先前基于长期记忆(LSTM)的神经模型。该代码和预培训模型将免费提供给社区。
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Controlled text generation is a very important task in the arena of natural language processing due to its promising applications. In order to achieve this task we mainly introduce the novel soft prompt tuning method of using soft prompts at both encoder and decoder levels together in a T5 model and investigate the performance as the behaviour of an additional soft prompt related to the decoder of a T5 model in controlled text generation remained unexplored. Then we also investigate the feasibility of steering the output of this extended soft prompted T5 model at decoder level and finally analyse the utility of generated text to be used in AI related tasks such as training AI models with an interpretability analysis of the classifier trained with synthetic text, as there is a lack of proper analysis of methodologies in generating properly labelled data to be utilized in AI tasks. Through the performed in-depth intrinsic and extrinsic evaluations of this generation model along with the artificially generated data, we found that this model produced better results compared to the T5 model with a single soft prompt at encoder level and the sentiment classifier trained using this artificially generated data can produce comparable classification results to the results of a classifier trained with real labelled data and also the classifier decision is interpretable with respect to the input text content.
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We present a new algorithm to learn a deep neural network model robust against adversarial attacks. Previous algorithms demonstrate an adversarially trained Bayesian Neural Network (BNN) provides improved robustness. We recognize the adversarial learning approach for approximating the multi-modal posterior distribution of a Bayesian model can lead to mode collapse; consequently, the model's achievements in robustness and performance are sub-optimal. Instead, we first propose preventing mode collapse to better approximate the multi-modal posterior distribution. Second, based on the intuition that a robust model should ignore perturbations and only consider the informative content of the input, we conceptualize and formulate an information gain objective to measure and force the information learned from both benign and adversarial training instances to be similar. Importantly. we prove and demonstrate that minimizing the information gain objective allows the adversarial risk to approach the conventional empirical risk. We believe our efforts provide a step toward a basis for a principled method of adversarially training BNNs. Our model demonstrate significantly improved robustness--up to 20%--compared with adversarial training and Adv-BNN under PGD attacks with 0.035 distortion on both CIFAR-10 and STL-10 datasets.
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图形神经网络(GNNS)在许多图形挖掘任务中取得了巨大的成功,这些任务从消息传递策略中受益,该策略融合了局部结构和节点特征,从而为更好的图表表示学习。尽管GNN成功,并且与其他类型的深神经网络相似,但发现GNN容易受到图形结构和节点特征的不明显扰动。已经提出了许多对抗性攻击,以披露在不同的扰动策略下创建对抗性例子的GNN的脆弱性。但是,GNNS对成功后门攻击的脆弱性直到最近才显示。在本文中,我们披露了陷阱攻击,这是可转移的图形后门攻击。核心攻击原则是用基于扰动的触发器毒化训练数据集,这可以导致有效且可转移的后门攻击。图形的扰动触发是通过通过替代模型的基于梯度的得分矩阵在图形结构上执行扰动动作来生成的。与先前的作品相比,陷阱攻击在几种方面有所不同:i)利用替代图卷积网络(GCN)模型来生成基于黑盒的后门攻击的扰动触发器; ii)它产生了没有固定模式的样品特异性扰动触发器; iii)在使用锻造中毒训练数据集训练时,在GNN的背景下,攻击转移到了不同​​的GNN模型中。通过对四个现实世界数据集进行广泛的评估,我们证明了陷阱攻击使用四个现实世界数据集在四个不同流行的GNN中构建可转移的后门的有效性
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机器学习模型严重易于来自对抗性示例的逃避攻击。通常,对逆势示例的修改输入类似于原始输入的修改输入,在WhiteBox设置下由对手的WhiteBox设置构成,完全访问模型。然而,最近的攻击已经显示出使用BlackBox攻击的对逆势示例的查询号显着减少。特别是,警报是从越来越多的机器学习提供的经过培训的模型的访问界面中利用分类决定作为包括Google,Microsoft,IBM的服务提供商,并由包含这些模型的多种应用程序使用的服务提供商来利用培训的模型。对手仅利用来自模型的预测标签的能力被区别为基于决策的攻击。在我们的研究中,我们首先深入潜入最近的ICLR和SP的最先进的决策攻击,以突出发现低失真对抗采用梯度估计方法的昂贵性质。我们开发了一种强大的查询高效攻击,能够避免在梯度估计方法中看到的嘈杂渐变中的局部最小和误导中的截留。我们提出的攻击方法,ramboattack利用随机块坐标下降的概念来探索隐藏的分类器歧管,针对扰动来操纵局部输入功能以解决梯度估计方法的问题。重要的是,ramboattack对对对手和目标类别可用的不同样本输入更加强大。总的来说,对于给定的目标类,ramboattack被证明在实现给定查询预算的较低失真时更加强大。我们使用大规模的高分辨率ImageNet数据集来策划我们的广泛结果,并在GitHub上开源我们的攻击,测试样本和伪影。
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深度神经网络容易受到来自对抗性投入的攻击,并且最近,特洛伊木马误解或劫持模型的决定。我们通过探索有界抗逆性示例空间和生成的对抗网络内的自然输入空间来揭示有界面的对抗性实例 - 通用自然主义侵害贴片的兴趣类 - 我们呼叫TNT。现在,一个对手可以用一个自然主义的补丁来手臂自己,不太恶意,身体上可实现,高效 - 实现高攻击成功率和普遍性。 TNT是普遍的,因为在场景中的TNT中捕获的任何输入图像都将:i)误导网络(未确定的攻击);或ii)迫使网络进行恶意决定(有针对性的攻击)。现在,有趣的是,一个对抗性补丁攻击者有可能发挥更大的控制水平 - 选择一个独立,自然的贴片的能力,与被限制为嘈杂的扰动的触发器 - 到目前为止只有可能与特洛伊木马攻击方法有可能干扰模型建设过程,以嵌入风险发现的后门;但是,仍然意识到在物理世界中部署的补丁。通过对大型视觉分类任务的广泛实验,想象成在其整个验证集50,000张图像中进行评估,我们展示了TNT的现实威胁和攻击的稳健性。我们展示了攻击的概括,以创建比现有最先进的方法实现更高攻击成功率的补丁。我们的结果表明,攻击对不同的视觉分类任务(CIFAR-10,GTSRB,PUBFIG)和多个最先进的深神经网络,如WieredEnet50,Inception-V3和VGG-16。
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A recent trojan attack on deep neural network (DNN) models is one insidious variant of data poisoning attacks. Trojan attacks exploit an effective backdoor created in a DNN model by leveraging the difficulty in interpretability of the learned model to misclassify any inputs signed with the attacker's chosen trojan trigger. Since the trojan trigger is a secret guarded and exploited by the attacker, detecting such trojan inputs is a challenge, especially at run-time when models are in active operation. This work builds STRong Intentional Perturbation (STRIP) based run-time trojan attack detection system and focuses on vision system. We intentionally perturb the incoming input, for instance by superimposing various image patterns, and observe the randomness of predicted classes for perturbed inputs from a given deployed model-malicious or benign. A low entropy in predicted classes violates the input-dependence property of a benign model and implies the presence of a malicious input-a characteristic of a trojaned input. The high efficacy of our method is validated through case studies on three popular and contrasting datasets: MNIST, CIFAR10 and GTSRB. We achieve an overall false acceptance rate (FAR) of less than 1%, given a preset false rejection rate (FRR) of 1%, for different types of triggers. Using CIFAR10 and GTSRB, we have empirically achieved result of 0% for both FRR and FAR. We have also evaluated STRIP robustness against a number of trojan attack variants and adaptive attacks.
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