数值验证是机器学习研究的核心,因为它允许评估新方法的实际影响,并确认理论和实践之间的一致性。然而,该领域的快速发展构成了一些挑战:研究人员面临着大量的方法来比较,有限的透明度和最佳实践的共识以及乏味的重新实施工作。结果,验证通常是非常部分的,这可能会导致错误的结论,从而减慢研究的进展。我们提出了Benchopt,这是一个协作框架,旨在在跨编程语言和硬件体系结构的机器学习中自动化,复制和发布优化基准。 Benchopt通过提供用于运行,共享和扩展实验的现成工具来简化社区的基准测试。为了展示其广泛的可用性,我们在三个标准学习任务上展示基准:$ \ ell_2 $ regulaine的逻辑回归,套索和RESNET18用于图像分类的培训。这些基准强调了关键的实际发现,这些发现对这些问题的最新问题更加细微,这表明在实际评估中,魔鬼在细节上。我们希望Benchopt能在社区中促进合作工作,从而改善研究结果的可重复性。
translated by 谷歌翻译
切成薄片的距离(SW)是一种计算有效的,理论上是Wasserstein距离的替代方案。然而,关于切片的分布,其统计特性(超出统一度量)的文献很少。为了为这一研究带来新的贡献,我们利用了Pac-bayesian理论和SW实际取决于切片分布依赖的Gibbs风险的中心观察,而Pac-Bayesian的数量范围已经设计为表征。我们提供四种类型的结果:i)在我们称为自适应切片的距离距离的豆豆泛化范围,即针对任何切片的分布定义的距离,ii)学习切片分布的过程最大歧视性的SW,通过优化我们的Pac-bayesian边界,iii)关于如何通过我们的理论来解释所谓的分布分布切片的距离,以及我们发现的经验例证。
translated by 谷歌翻译
建模物理系统的数据驱动方法无法推广到与学习域共享相同一般动态的看不见的系统,但与不同的物理环境相对应。我们为此关键问题提出了一个新的框架,即上下文知识的动态适应(CODA),该框架考虑了整个系统之间的分布转移,以快速有效地适应新的动力学。 CODA利用多个环境,每个环境都与不同的动态相关联,并学会将动态模型定为上下文参数(特定于每个环境)。调节是通过超网络进行的,并从观察到的数据与上下文向量共同学习。提出的公式限制了搜索假设空间,以促进跨环境的快速适应和更好的概括。我们从理论上激励我们的方法,并在一组非线性动力学上显示出最新的概括结果,这是多种应用领域的代​​表。我们还在这些系统上还显示,可以从上下文向量中推断出新的系统参数,并以最小的监督为准。
translated by 谷歌翻译
This paper presents a methodology for integrating machine learning techniques into metaheuristics for solving combinatorial optimization problems. Namely, we propose a general machine learning framework for neighbor generation in metaheuristic search. We first define an efficient neighborhood structure constructed by applying a transformation to a selected subset of variables from the current solution. Then, the key of the proposed methodology is to generate promising neighbors by selecting a proper subset of variables that contains a descent of the objective in the solution space. To learn a good variable selection strategy, we formulate the problem as a classification task that exploits structural information from the characteristics of the problem and from high-quality solutions. We validate our methodology on two metaheuristic applications: a Tabu Search scheme for solving a Wireless Network Optimization problem and a Large Neighborhood Search heuristic for solving Mixed-Integer Programs. The experimental results show that our approach is able to achieve a satisfactory trade-off between the exploration of a larger solution space and the exploitation of high-quality solution regions on both applications.
translated by 谷歌翻译
We investigate the asymptotic properties of deep Residual networks (ResNets) as the number of layers increases. We first show the existence of scaling regimes for trained weights markedly different from those implicitly assumed in the neural ODE literature. We study the convergence of the hidden state dynamics in these scaling regimes, showing that one may obtain an ODE, a stochastic differential equation (SDE) or neither of these. In particular, our findings point to the existence of a diffusive regime in which the deep network limit is described by a class of stochastic differential equations (SDEs). Finally, we derive the corresponding scaling limits for the backpropagation dynamics.
translated by 谷歌翻译
Warning: this paper contains content that may be offensive or upsetting. Considering the large amount of content created online by the minute, slang-aware automatic tools are critically needed to promote social good, and assist policymakers and moderators in restricting the spread of offensive language, abuse, and hate speech. Despite the success of large language models and the spontaneous emergence of slang dictionaries, it is unclear how far their combination goes in terms of slang understanding for downstream social good tasks. In this paper, we provide a framework to study different combinations of representation learning models and knowledge resources for a variety of downstream tasks that rely on slang understanding. Our experiments show the superiority of models that have been pre-trained on social media data, while the impact of dictionaries is positive only for static word embeddings. Our error analysis identifies core challenges for slang representation learning, including out-of-vocabulary words, polysemy, variance, and annotation disagreements, which can be traced to characteristics of slang as a quickly evolving and highly subjective language.
translated by 谷歌翻译
Warning: this paper contains content that may be offensive or upsetting. In the current context where online platforms have been effectively weaponized in a variety of geo-political events and social issues, Internet memes make fair content moderation at scale even more difficult. Existing work on meme classification and tracking has focused on black-box methods that do not explicitly consider the semantics of the memes or the context of their creation. In this paper, we pursue a modular and explainable architecture for Internet meme understanding. We design and implement multimodal classification methods that perform example- and prototype-based reasoning over training cases, while leveraging both textual and visual SOTA models to represent the individual cases. We study the relevance of our modular and explainable models in detecting harmful memes on two existing tasks: Hate Speech Detection and Misogyny Classification. We compare the performance between example- and prototype-based methods, and between text, vision, and multimodal models, across different categories of harmfulness (e.g., stereotype and objectification). We devise a user-friendly interface that facilitates the comparative analysis of examples retrieved by all of our models for any given meme, informing the community about the strengths and limitations of these explainable methods.
translated by 谷歌翻译
Assessing the critical view of safety in laparoscopic cholecystectomy requires accurate identification and localization of key anatomical structures, reasoning about their geometric relationships to one another, and determining the quality of their exposure. In this work, we propose to capture each of these aspects by modeling the surgical scene with a disentangled latent scene graph representation, which we can then process using a graph neural network. Unlike previous approaches using graph representations, we explicitly encode in our graphs semantic information such as object locations and shapes, class probabilities and visual features. We also incorporate an auxiliary image reconstruction objective to help train the latent graph representations. We demonstrate the value of these components through comprehensive ablation studies and achieve state-of-the-art results for critical view of safety prediction across multiple experimental settings.
translated by 谷歌翻译
Reinforcement Learning has emerged as a strong alternative to solve optimization tasks efficiently. The use of these algorithms highly depends on the feedback signals provided by the environment in charge of informing about how good (or bad) the decisions made by the learned agent are. Unfortunately, in a broad range of problems the design of a good reward function is not trivial, so in such cases sparse reward signals are instead adopted. The lack of a dense reward function poses new challenges, mostly related to exploration. Imitation Learning has addressed those problems by leveraging demonstrations from experts. In the absence of an expert (and its subsequent demonstrations), an option is to prioritize well-suited exploration experiences collected by the agent in order to bootstrap its learning process with good exploration behaviors. However, this solution highly depends on the ability of the agent to discover such trajectories in the early stages of its learning process. To tackle this issue, we propose to combine imitation learning with intrinsic motivation, two of the most widely adopted techniques to address problems with sparse reward. In this work intrinsic motivation is used to encourage the agent to explore the environment based on its curiosity, whereas imitation learning allows repeating the most promising experiences to accelerate the learning process. This combination is shown to yield an improved performance and better generalization in procedurally-generated environments, outperforming previously reported self-imitation learning methods and achieving equal or better sample efficiency with respect to intrinsic motivation in isolation.
translated by 谷歌翻译
Because of the considerable heterogeneity and complexity of the technological landscape, building accurate models to forecast is a challenging endeavor. Due to their high prevalence in many complex systems, S-curves are a popular forecasting approach in previous work. However, their forecasting performance has not been directly compared to other technology forecasting approaches. Additionally, recent developments in time series forecasting that claim to improve forecasting accuracy are yet to be applied to technological development data. This work addresses both research gaps by comparing the forecasting performance of S-curves to a baseline and by developing an autencoder approach that employs recent advances in machine learning and time series forecasting. S-curves forecasts largely exhibit a mean average percentage error (MAPE) comparable to a simple ARIMA baseline. However, for a minority of emerging technologies, the MAPE increases by two magnitudes. Our autoencoder approach improves the MAPE by 13.5% on average over the second-best result. It forecasts established technologies with the same accuracy as the other approaches. However, it is especially strong at forecasting emerging technologies with a mean MAPE 18% lower than the next best result. Our results imply that a simple ARIMA model is preferable over the S-curve for technology forecasting. Practitioners looking for more accurate forecasts should opt for the presented autoencoder approach.
translated by 谷歌翻译