We study the problem of model selection in causal inference, specifically for the case of conditional average treatment effect (CATE) estimation under binary treatments. Unlike model selection in machine learning, we cannot use the technique of cross-validation here as we do not observe the counterfactual potential outcome for any data point. Hence, we need to design model selection techniques that do not explicitly rely on counterfactual data. As an alternative to cross-validation, there have been a variety of proxy metrics proposed in the literature, that depend on auxiliary nuisance models also estimated from the data (propensity score model, outcome regression model). However, the effectiveness of these metrics has only been studied on synthetic datasets as we can observe the counterfactual data for them. We conduct an extensive empirical analysis to judge the performance of these metrics, where we utilize the latest advances in generative modeling to incorporate multiple realistic datasets. We evaluate 9 metrics on 144 datasets for selecting between 415 estimators per dataset, including datasets that closely mimic real-world datasets. Further, we use the latest techniques from AutoML to ensure consistent hyperparameter selection for nuisance models for a fair comparison across metrics.

可识别表示学习的理论旨在构建通用方法，从低水平的感觉数据中提取高级潜在（因果）因素。大多数现有的作品都集中在可识别的表示学习中，并依赖于对潜在因素（因果）因素的分配假设。但是，实际上，我们通常还可以访问用于表示学习的介入数据。我们如何利用介入数据来帮助识别高级潜在的潜伏期？为此，我们探讨了在这项工作中可识别的代表学习中介入数据的作用。我们研究潜在因果因素在没有介入数据的情况下，在未介入数据的情况下，在最小的分布假设上。我们证明，如果真实的潜在变量通过多项式函数映射到观察到的高维数据，则通过最小化自动装饰器的标准重建损失来表示学习，将确定真正的潜在潜在的潜在潜在转化。如果我们进一步访问了由硬$ $ do $ $干预产生的干预数据，那么我们就可以识别出这些干预潜在的潜在潜在的潜在潜在的潜在潜在的潜在潜在的潜伏期。

The availability of challenging benchmarks has played a key role in the recent progress of machine learning. In cooperative multi-agent reinforcement learning, the StarCraft Multi-Agent Challenge (SMAC) has become a popular testbed for centralised training with decentralised execution. However, after years of sustained improvement on SMAC, algorithms now achieve near-perfect performance. In this work, we conduct new analysis demonstrating that SMAC is not sufficiently stochastic to require complex closed-loop policies. In particular, we show that an open-loop policy conditioned only on the timestep can achieve non-trivial win rates for many SMAC scenarios. To address this limitation, we introduce SMACv2, a new version of the benchmark where scenarios are procedurally generated and require agents to generalise to previously unseen settings (from the same distribution) during evaluation. We show that these changes ensure the benchmark requires the use of closed-loop policies. We evaluate state-of-the-art algorithms on SMACv2 and show that it presents significant challenges not present in the original benchmark. Our analysis illustrates that SMACv2 addresses the discovered deficiencies of SMAC and can help benchmark the next generation of MARL methods. Videos of training are available at https://sites.google.com/view/smacv2

A reliable critic is central to on-policy actor-critic learning. But it becomes challenging to learn a reliable critic in a multi-agent sparse reward scenario due to two factors: 1) The joint action space grows exponentially with the number of agents 2) This, combined with the reward sparseness and environment noise, leads to large sample requirements for accurate learning. We show that regularising the critic with spectral normalization (SN) enables it to learn more robustly, even in multi-agent on-policy sparse reward scenarios. Our experiments show that the regularised critic is quickly able to learn from the sparse rewarding experience in the complex SMAC and RWARE domains. These findings highlight the importance of regularisation in the critic for stable learning.

There has been a recent explosion of impressive generative models that can produce high quality images (or videos) conditioned on text descriptions. However, all such approaches rely on conditional sentences that contain unambiguous descriptions of scenes and main actors in them. Therefore employing such models for more complex task of story visualization, where naturally references and co-references exist, and one requires to reason about when to maintain consistency of actors and backgrounds across frames/scenes, and when not to, based on story progression, remains a challenge. In this work, we address the aforementioned challenges and propose a novel autoregressive diffusion-based framework with a visual memory module that implicitly captures the actor and background context across the generated frames. Sentence-conditioned soft attention over the memories enables effective reference resolution and learns to maintain scene and actor consistency when needed. To validate the effectiveness of our approach, we extend the MUGEN dataset and introduce additional characters, backgrounds and referencing in multi-sentence storylines. Our experiments for story generation on the MUGEN, the PororoSV and the FlintstonesSV dataset show that our method not only outperforms prior state-of-the-art in generating frames with high visual quality, which are consistent with the story, but also models appropriate correspondences between the characters and the background.

We discuss a platform that has both software and hardware components, and whose purpose is to support research into characterizing and mitigating the sim-to-real gap in robotics and vehicle autonomy engineering. The software is operating-system independent and has three main components: a simulation engine called Chrono, which supports high-fidelity vehicle and sensor simulation; an autonomy stack for algorithm design and testing; and a development environment that supports visualization and hardware-in-the-loop experimentation. The accompanying hardware platform is a 1/6th scale vehicle augmented with reconfigurable mountings for computing, sensing, and tracking. Since this vehicle platform has a digital twin within the simulation environment, one can test the same autonomy perception, state estimation, or controls algorithms, as well as the processors they run on, in both simulation and reality. A demonstration is provided to show the utilization of this platform for autonomy research. Future work will concentrate on augmenting ART/ATK with support for a full-sized Chevy Bolt EUV, which will be made available to this group in the immediate future.

Reinforcementlearning(RL)folkloresuggeststhathistory-basedfunctionapproximationmethods,suchas recurrent neural nets or history-based state abstraction, perform better than their memory-less counterparts, due to the fact that function approximation in Markov decision processes (MDP) can be viewed as inducing a Partially observable MDP. However, there has been little formal analysis of such history-based algorithms, as most existing frameworks focus exclusively on memory-less features. In this paper, we introduce a theoretical framework for studying the behaviour of RL algorithms that learn to control an MDP using history-based feature abstraction mappings. Furthermore, we use this framework to design a practical RL algorithm and we numerically evaluate its effectiveness on a set of continuous control tasks.

我们提出了一种使用绑架过程，在给定的答案集编程（ASP）规则集（ASP）规则集方面生成可能的查询证明，该过程仅根据输入规则自动构建了陈腐的空间。给定一组（可能是空的）用户提供的事实，我们的方法会渗透到需要查询的任何其他事实，然后输出这些额外的事实，而无需用户需要明确指定所有占有无误的空间。我们还提出了一种方法，以生成与查询的理由图相对应的一组定向边缘。此外，通过不同形式的隐式术语替换，我们的方法可以考虑用户提供的事实并适当修改绑架解决方案。过去的绑架工作主要基于目标定向方法。但是，这些方法可能导致并非真正声明的求解器。关于实现绑架的绑架者，例如Clingo ASP求解器，做出的工作要少得多。我们描述了可以直接在Clingo中运行的新型ASP程序，以产生绑架解决方案和定向边缘集，而无需修改基础求解引擎。

该手稿解决了预测出院后全因住院再入院或死亡的同时问题，并量化放电放置在防止这些不良事件中的影响。为此，我们开发了一个固有的可解释的多级贝叶斯建模框架，该框架灵感来自重新激活的深神经网络的分段线性。在生存模型中，我们明确调整了混淆，以量化局部平均治疗效果以进行放电的干预措施。从2008年和2011年开始，我们对5％的Medicare受益人样本进行了培训，然后在2012年的索赔中测试了该模型。该模型对30天全因素外的再选中（使用官方CMS方法定义）的分类精度进行了评估，该模型对XGBoost，Logistic回归（功能工程后）和对同一数据进行训练的贝叶斯深神经网络的执行方式相似。该模型对30天的分类任务进行了预测的30天分类任务，该任务是使用剩下的未来数据进行测试，该模型的AUROC约为0.76，AUPRC约为0.50（相对于测试数据中的总体阳性速率），AUPRC的AUPRC达到了约0.76，而AUPRC的AUPRC则达到了AUPRC，则获得了AUPRC。证明人们不需要为准确性而牺牲可解释性。此外，该模型的测试AUROC为0.78，分类为90天全因素外再入院或死亡。我们很容易地凝视着我们固有的可解释模型，总结了其主要发现。此外，我们演示了Black-box Perthoc解释器工具的形状如何生成不受拟合模型支持的解释 - 如果以面值为单位，则没有提供足够的上下文来使模型可操作。

对于医疗保健提供者提供适当的患者护理的准确和详细说明，包括患者时​​间表中的药物变化，至关重要。医疗保健提供者或患者本身可能会引发患者药物的改变。用药更改采用多种形式，包括处方药和相关剂量修饰。这些更改提供了有关患者整体健康以及导致当前护理的理由的信息。然后，未来的护理可以基于患者的最终状态。这项工作探讨了从自由文本临床注释中自动提取药物变化信息。上下文药物事件数据集（CMED）是临床注释的语料库，其注释可以通过多种变化相关的属性来表征药物变化，包括更改的类型（启动，停止，增加等），更改，时间性，时间性，时间性，时间性，时间性，时间。改变可能性和否定。使用CMED，我们确定了临床文本中的药物提及，并提出了三个新型的基于BERT的新型基于BERT的系统，以解决注释的药物变化特征。我们证明，我们建议的体系结构改善了对CMED的初始工作改善药物变更分类的性能。我们确定了0.959 F1的高性能的药物提及，我们提出的系统将药物变化及其属性分类为0.827 F1。