This report presents the evaluation approach developed for the DARPA Big Mechanism program, which aimed at developing computer systems that will read research papers, integrate the information into a computer model of cancer mechanisms, and frame new hypotheses. We employed an iterative, incremental approach to the evaluation of the three phases of the program. In Phase I, we evaluated the ability of system and human teams ability to read-with-a-model to capture mechanistic information from the biomedical literature, integrated with information from expert curated biological databases. In Phase II we evaluated the ability of systems to assemble fragments of information into a mechanistic model. The Phase III evaluation focused on the ability of systems to provide explanations of experimental observations based on models assembled (largely automatically) by the Big Mechanism process. The evaluation for each phase built on earlier evaluations and guided developers towards creating capabilities for the new phase. The report describes our approach, including innovations such as a reference set (a curated data set limited to major findings of each paper) to assess the accuracy of systems in extracting mechanistic findings in the absence of a gold standard, and a method to evaluate model-based explanations of experimental data. Results of the evaluation and supporting materials are included in the appendices.
translated by 谷歌翻译
软件错误预测预测是一个活跃的研究领域,许多因素影响了预测性能。但是,除了一项初始工作外,尚未研究学习方法(即,用于培训和预测目标变量的数据的细节)对预测性能的影响。本文探讨了两种学习方法的影响,即Useallpredictall和usePredictPost,对软件错误预测预测的性能,包括释放内部和跨释放。经验结果基于从十二个开源项目的64个版本中提取的数据。结果表明,学习方法对分类表现有实质性的,通常未被承认的影响。具体而言,使用USEALLPREDICTALL导致的性能要比使用释放和跨释放的UsePrepredictPost学习方法要好得多。此外,本文发现,对于释放内部预测,分类性能的这种差异是由于两种学习方法中的类不平衡级别引起的。解决课堂失衡时,消除了学习方法之间的性能差异。我们的发现暗示,应始终明确识别学习方法及其对软件缺陷预订预测的影响。本文最后讨论了我们的研究和实践结果的潜在后果。
translated by 谷歌翻译
Large, labeled datasets have driven deep learning methods to achieve expert-level performance on a variety of medical imaging tasks. We present CheXpert, a large dataset that contains 224,316 chest radiographs of 65,240 patients. We design a labeler to automatically detect the presence of 14 observations in radiology reports, capturing uncertainties inherent in radiograph interpretation. We investigate different approaches to using the uncertainty labels for training convolutional neural networks that output the probability of these observations given the available frontal and lateral radiographs. On a validation set of 200 chest radiographic studies which were manually annotated by 3 board-certified radiologists, we find that different uncertainty approaches are useful for different pathologies. We then evaluate our best model on a test set composed of 500 chest radiographic studies annotated by a consensus of 5 board-certified radiologists, and compare the performance of our model to that of 3 additional radiologists in the detection of 5 selected pathologies. On Cardiomegaly, Edema, and Pleural Effusion, the model ROC and PR curves lie above all 3 radiologist operating points. We release the dataset to the public as a standard benchmark to evaluate performance of chest radiograph interpretation models. 1
translated by 谷歌翻译
Machine learning about language can be improved by supplying it with specific knowledge and sources of external information. We present here a new version of the linked open data resource ConceptNet that is particularly well suited to be used with modern NLP techniques such as word embeddings.ConceptNet is a knowledge graph that connects words and phrases of natural language with labeled edges. Its knowledge is collected from many sources that include expertcreated resources, crowd-sourcing, and games with a purpose. It is designed to represent the general knowledge involved in understanding language, improving natural language applications by allowing the application to better understand the meanings behind the words people use.When ConceptNet is combined with word embeddings acquired from distributional semantics (such as word2vec), it provides applications with understanding that they would not acquire from distributional semantics alone, nor from narrower resources such as WordNet or DBPedia. We demonstrate this with state-of-the-art results on intrinsic evaluations of word relatedness that translate into improvements on applications of word vectors, including solving SAT-style analogies.• A net is used for catching fish.• "Leaves" is a form of the word "leaf ".• The word cold in English is studený in Czech.• O alimento é usado para comer [Food is used for eating].
translated by 谷歌翻译