Of late, insurance fraud detection has assumed immense significance owing to the huge financial & reputational losses fraud entails and the phenomenal success of the fraud detection techniques. Insurance is majorly divided into two categories: (i) Life and (ii) Non-life. Non-life insurance in turn includes health insurance and auto insurance among other things. In either of the categories, the fraud detection techniques should be designed in such a way that they capture as many fraudulent transactions as possible. Owing to the rarity of fraudulent transactions, in this paper, we propose a chaotic variational autoencoder (C-VAE to perform one-class classification (OCC) on genuine transactions. Here, we employed the logistic chaotic map to generate random noise in the latent space. The effectiveness of C-VAE is demonstrated on the health insurance fraud and auto insurance datasets. We considered vanilla Variational Auto Encoder (VAE) as the baseline. It is observed that C-VAE outperformed VAE in both datasets. C-VAE achieved a classification rate of 77.9% and 87.25% in health and automobile insurance datasets respectively. Further, the t-test conducted at 1% level of significance and 18 degrees of freedom infers that C-VAE is statistically significant than the VAE.
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The rapid growth of machine translation (MT) systems has necessitated comprehensive studies to meta-evaluate evaluation metrics being used, which enables a better selection of metrics that best reflect MT quality. Unfortunately, most of the research focuses on high-resource languages, mainly English, the observations for which may not always apply to other languages. Indian languages, having over a billion speakers, are linguistically different from English, and to date, there has not been a systematic study of evaluating MT systems from English into Indian languages. In this paper, we fill this gap by creating an MQM dataset consisting of 7000 fine-grained annotations, spanning 5 Indian languages and 7 MT systems, and use it to establish correlations between annotator scores and scores obtained using existing automatic metrics. Our results show that pre-trained metrics, such as COMET, have the highest correlations with annotator scores. Additionally, we find that the metrics do not adequately capture fluency-based errors in Indian languages, and there is a need to develop metrics focused on Indian languages. We hope that our dataset and analysis will help promote further research in this area.
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The number of international benchmarking competitions is steadily increasing in various fields of machine learning (ML) research and practice. So far, however, little is known about the common practice as well as bottlenecks faced by the community in tackling the research questions posed. To shed light on the status quo of algorithm development in the specific field of biomedical imaging analysis, we designed an international survey that was issued to all participants of challenges conducted in conjunction with the IEEE ISBI 2021 and MICCAI 2021 conferences (80 competitions in total). The survey covered participants' expertise and working environments, their chosen strategies, as well as algorithm characteristics. A median of 72% challenge participants took part in the survey. According to our results, knowledge exchange was the primary incentive (70%) for participation, while the reception of prize money played only a minor role (16%). While a median of 80 working hours was spent on method development, a large portion of participants stated that they did not have enough time for method development (32%). 25% perceived the infrastructure to be a bottleneck. Overall, 94% of all solutions were deep learning-based. Of these, 84% were based on standard architectures. 43% of the respondents reported that the data samples (e.g., images) were too large to be processed at once. This was most commonly addressed by patch-based training (69%), downsampling (37%), and solving 3D analysis tasks as a series of 2D tasks. K-fold cross-validation on the training set was performed by only 37% of the participants and only 50% of the participants performed ensembling based on multiple identical models (61%) or heterogeneous models (39%). 48% of the respondents applied postprocessing steps.
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原则上,将变异自动编码器(VAE)应用于顺序数据提供了一种用于控制序列生成,操纵和结构化表示学习的方法。但是,训练序列VAE具有挑战性:自回归解码器通常可以解释数据而无需使用潜在空间,即后置倒塌。为了减轻这种情况,最新的模型通过将均匀的随机辍学量应用于解码器输入来削弱强大的解码器。从理论上讲,我们表明,这可以消除解码器输入提供的点式互信息,该信息通过利用潜在空间来补偿。然后,我们提出了一种对抗性训练策略,以实现基于信息的随机辍学。与标准文本基准数据集上的均匀辍学相比,我们的目标方法同时提高了序列建模性能和潜在空间中捕获的信息。
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人们现在将社交媒体网站视为其唯一信息来源,因为它们的受欢迎程度。大多数人通过社交媒体获取新闻。同时,近年来,假新闻在社交媒体平台上成倍增长。几种基于人工智能的解决方案用于检测假新闻,已显示出令人鼓舞的结果。另一方面,这些检测系统缺乏解释功能,即解释为什么他们做出预测的能力。本文在可解释的假新闻检测中突出了当前的艺术状态。我们讨论了当前可解释的假新闻检测模型中的陷阱,并介绍了我们正在进行的有关多模式可解释的假新闻检测模型的研究。
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构建强大的通用对象检测框架需要扩展到更大的标签空间和更大的培训数据集。但是,大规模获取数千个类别的注释是高昂的成本。我们提出了一种新颖的方法,该方法利用了最近的视觉和语言模型中可用的丰富语义来将对象定位和分类在未标记的图像中,从而有效地生成了伪标签以进行对象检测。从通用和类别的区域建议机制开始,我们使用视觉和语言模型将图像的每个区域分类为下游任务所需的任何对象类别。我们在两个特定的任务(开放式摄影检测检测)中演示了生成的伪标签的值,其中模型需要概括为看不见的对象类别以及半监督对象检测,其中可以使用其他未标记的图像来改善模型。我们的经验评估显示了伪标签在这两个任务中的有效性,我们在其中优于竞争基准并实现了开放式摄制对象检测的新颖最新。我们的代码可在https://github.com/xiaofeng94/vl-plm上找到。
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表达性和计算便宜的两分图神经网络(GNN)已被证明是基于深度学习的混合成分线性程序(MILP)求解器的重要组成部分。最近的工作证明了此类GNN在分支结合(B&B)求解器中取代分支(可变选择)启发式方面的有效性。这些GNN经过训练,离线和集合,以模仿一个非常好但计算昂贵的分支启发式,强大的分支。鉴于B&B会导致子隔间树,我们问(a)目标启发式启发式在B&B树的邻近节点之间是否存在很强的依赖性,并且(b)如果是这样,我们是否可以将它们合并到我们的培训程序。具体来说,我们发现,有了强大的分支启发式,孩子节点的最佳选择通常是父母的第二好的选择。我们将其称为“回顾”现象。令人惊讶的是,Gasse等人的典型分支GNN。 (2019年)经常错过这个简单的“答案”。为了通过将回顾现象纳入GNN来更紧密地模仿目标行为,我们提出了两种方法:(a)标准跨凝性损失函数的目标平滑,(b)添加父级(PAT)target(PAT)回顾量学期。最后,我们提出了一个模型选择框架,以结合更难构建的目标,例如在最终模型中解决时间。通过对标准基准实例进行广泛的实验,我们表明我们的提案导致B&B树大小的22%减少,并且在解决时间的解决方案中提高了15%。
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降水控制地球气候,其日常时空波动具有重大的社会经济影响。通过改善温度和压力等各种物理领域的预测来衡量数值天气预测(NWP)的进步;然而,降水预测中存在很大的偏见。我们通过深度学习来增强著名的NWP模型CFSV2的输出,以创建一个混合模型,该模型在1日,2天和3天的交货时间内改善了短期全局降水量。为了混合使用,我们通过使用修改的DLWP-CS体系结构来解决全局数据的球形,从而将所有字段转换为立方体投影。动态模型沉淀和表面温度输出被喂入改良的DLWP-CS(UNET),以预测地面真相降水。虽然CFSV2的平均偏差为土地+5至+7毫米/天,但多元深度学习模型将其降低到-1至+1 mm/天。卡特里娜飓风在2005年,伊万飓风,2010年的中国洪水,2005年的印度洪水和2008年的缅甸风暴纳尔吉斯(Myanmar Storm Nargis)用于确认混合动力学深度学习模型的技能大大提高。 CFSV2通常在空间模式中显示中度至大偏置,并在短期时间尺度上高估了沉淀。拟议的深度学习增强了NWP模型可以解决这些偏见,并大大改善了预测降水的空间模式和幅度。与CFSV2相比,深度学习增强了CFSV2在重要的土地区域的平均偏差为1天铅1天。时空深度学习系统开辟了途径,以进一步提高全球短期降水预测的精度和准确性。
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语言模型既展示了定量的改进,又展示了新的定性功能,随着规模的增加。尽管它们具有潜在的变革性影响,但这些新能力的特征却很差。为了为未来的研究提供信息,为破坏性的新模型能力做准备,并改善社会有害的效果,至关重要的是,我们必须了解目前和近乎未来的能力和语言模型的局限性。为了应对这一挑战,我们介绍了超越模仿游戏基准(Big Bench)。 Big Bench目前由204个任务组成,由132家机构的442位作者贡献。任务主题是多样的,从语言学,儿童发展,数学,常识性推理,生物学,物理学,社会偏见,软件开发等等。 Big-Bench专注于被认为超出当前语言模型的功能的任务。我们评估了OpenAI的GPT型号,Google内部密集变压器体系结构和大型基础上的开关稀疏变压器的行为,跨越了数百万到数十亿个参数。此外,一个人类专家评估者团队执行了所有任务,以提供强大的基准。研究结果包括:模型性能和校准都随规模改善,但绝对的术语(以及与评估者的性能相比);在模型类中的性能非常相似,尽管带有稀疏性。逐渐和预测的任务通常涉及大量知识或记忆成分,而在临界规模上表现出“突破性”行为的任务通常涉及多个步骤或组成部分或脆性指标;社交偏见通常会随着含糊不清的环境而随着规模而增加,但这可以通过提示来改善。
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通过卫星摄像机获取关于地球表面的大面积的信息使我们能够看到远远超过我们在地面上看到的更多。这有助于我们在检测和监测土地使用模式,大气条件,森林覆盖和许多非上市方面的地区的物理特征。所获得的图像不仅跟踪连续的自然现象,而且对解决严重森林砍伐的全球挑战也至关重要。其中亚马逊盆地每年占最大份额。适当的数据分析将有助于利用可持续健康的氛围来限制对生态系统和生物多样性的不利影响。本报告旨在通过不同的机器学习和优越的深度学习模型用大气和各种陆地覆盖或土地使用亚马逊雨林的卫星图像芯片。评估是基于F2度量完成的,而用于损耗函数,我们都有S形跨熵以及Softmax交叉熵。在使用预先训练的ImageNet架构中仅提取功能之后,图像被间接馈送到机器学习分类器。鉴于深度学习模型,通过传输学习使用微调Imagenet预训练模型的集合。到目前为止,我们的最佳分数与F2度量为0.927。
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