Mixture of factor analyzer (MFA) model is an efficient model for the analysis of high dimensional data through which the factor-analyzer technique based on the covariance matrices reducing the number of free parameters. The model also provides an important methodology to determine latent groups in data. There are several pieces of research to extend the model based on the asymmetrical and/or with outlier datasets with some known computational limitations that have been examined in frequentist cases. In this paper, an MFA model with a rich and flexible class of skew normal (unrestricted) generalized hyperbolic (called SUNGH) distributions along with a Bayesian structure with several computational benefits have been introduced. The SUNGH family provides considerable flexibility to model skewness in different directions as well as allowing for heavy tailed data. There are several desirable properties in the structure of the SUNGH family, including, an analytically flexible density which leads to easing up the computation applied for the estimation of parameters. Considering factor analysis models, the SUNGH family also allows for skewness and heavy tails for both the error component and factor scores. In the present study, the advantages of using this family of distributions have been discussed and the suitable efficiency of the introduced MFA model using real data examples and simulation has been demonstrated.

通过变分贝叶斯近似来提出框架，用于拟合逆问题模型。与标准马尔可夫链蒙特卡罗方法相比，这种方法可确保对广泛的应用，良好的应用，良好的精度性能和降低的模型拟合时间来灵活。我们描述的变分贝叶斯的消息传递和因子图片段方法促进了简化的近似推理算法的实现，并形成软件开发的基础。这种方法允许将许多响应分布和惩罚抑制到逆问题模型中。尽管我们的工作被赋予了一个和二维响应变量，但我们展示了一个基础设施，其中还可以导出基于变量之间的无效弱交互的有效算法更新，以便在更高维度中的逆问题。通过生物医学和考古问题激励的图像处理应用程序作为图示。

近几十年来，技术进步使得可以收集大数据集。在这种情况下，基于模型的群集是一种非常流行的，灵活和可解释的方法，用于在明确定义的统计框架中进行数据探索。大型数据集的增加之一是缺失值更频繁。但是，传统方式（由于丢弃具有缺失的值或估算方法的观察）不是为聚类目的而设计的。此外，它们很少适用于常规情况，虽然在实践中频繁地缺失，但是当缺失取决于未观察到的数据值时，缺失就缺失（mnar）值，而且可能在观察到的数据值上。本文的目标是通过直接在基于模型的聚类算法内嵌入MNAR数据来提出一种新的方法。我们为数据和缺失数据指示器的联合分布进行了选择模型。它对应于数据分布的混合模型和缺失数据机制的一般Mnar模型，其可以取决于底层类（未知）和/或缺失变量本身的值。导出大量有意义的MNAR子模型，对每个子模型研究了参数的可识别性，这通常是任何MNAR提案的关键问题。考虑EM和随机EM算法估计。最后，我们对合成数据的提议子模型进行了实证评估，我们说明了我们的方法对医疗寄存器的方法，创伤者（R）数据集。

在本文中，我们介绍了一种用于学习非负矩阵分解（NMF）的概率模型，该模型通常用于预测数据中缺失值并在数据中找到隐藏模式，其中矩阵因子是与每个数据维度相关的潜在变量。通过在非负子空间上支持先验的先验，可以处理潜在因素的非阴性约束。采用基于Gibbs抽样的贝叶斯推理程序。我们在几个现实世界中的数据集上评估了该模型，包括Movielens 100K和Movielens 1M具有不同尺寸和尺寸的Movielens，并表明所提出的贝叶斯NMF GRRN模型可导致更好的预测，并避免与现有的贝叶斯NMF方法相比，避免过度适应。

我们考虑有限混合物（MFM）和Dirichlet工艺混合物（DPM）模型的贝叶斯混合物。最近的渐近理论已经确定，DPM高估了大型样本的聚类数量，并且两类模型的估计量对于不指定的群集的数量不一致，但是对有限样本分析的含义尚不清楚。拟合这些模型后的最终报告的估计通常是使用MCMC摘要技术获得的单个代表性聚类，但是尚不清楚这样的摘要估计簇的数量。在这里，我们通过模拟和对基因表达数据的应用进行了研究，发现（i）DPM甚至在有限样本中高估了簇数的数量，但仅在有限的程度上可以使用适当的摘要来纠正，并且（ii）（ii） ）错误指定会导致对DPM和MFM中集群数量的高估，但是结果通常仍然可以解释。我们提供了有关MCMC摘要的建议，并建议尽管MFM的渐近性能更具吸引力，这提供了强大的动力来偏爱它们，但使用MFMS和DPMS获得的结果通常在实践中非常相似。

与许多机器学习模型类似，群集加权模型（CWM）的准确性和速度都可以受到高维数据的阻碍，从而导致以前的作品对一种简约的技术，以减少“尺寸诅咒”对混合模型的影响。在这项工作中，我们回顾了集群加权模型（CWM）的背景研究。我们进一步表明，在庞大的高维数据的情况下，简约的技术不足以使混合模型蓬勃发展。我们通过使用“ FlexCWM” R软件包中的默认值选择位置参数的初始值来讨论一种用于检测隐藏组件的启发式。我们引入了一种称为T-分布的随机邻居嵌入（TSNE）的维度降低技术，以增强高维空间中的简约CWM。最初，CWM适用于回归，但出于分类目的，所有多级变量都会用一些噪声进行对数转换。模型的参数是通过预期最大化算法获得的。使用来自不同字段的实际数据集证明了讨论技术的有效性。

Matrix factorization exploits the idea that, in complex high-dimensional data, the actual signal typically lies in lower-dimensional structures. These lower dimensional objects provide useful insight, with interpretability favored by sparse structures. Sparsity, in addition, is beneficial in terms of regularization and, thus, to avoid over-fitting. By exploiting Bayesian shrinkage priors, we devise a computationally convenient approach for high-dimensional matrix factorization. The dependence between row and column entities is modeled by inducing flexible sparse patterns within factors. The availability of external information is accounted for in such a way that structures are allowed while not imposed. Inspired by boosting algorithms, we pair the the proposed approach with a numerical strategy relying on a sequential inclusion and estimation of low-rank contributions, with data-driven stopping rule. Practical advantages of the proposed approach are demonstrated by means of a simulation study and the analysis of soccer heatmaps obtained from new generation tracking data.

如今，贝叶斯推论的应用非常流行。在此框架中，通过其边际可能性或其商（称为贝叶斯因素）进行比较模型。但是，边际可能性取决于先前的选择。对于模型选择，与参数估计问题不同，即使是分散的先验也可能非常有用。此外，当先验不当时，相应模型的边际可能性就不确定。在这项工作中，我们讨论了边际可能性及其在模型选择中的作用的先验敏感性问题。我们还评论了使用非信息性先验，这在实践中是非常普遍的选择。讨论了一些实际建议，并描述了文献中提出的许多可能的解决方案，以设计用于模型选择的客观先验。其中一些还允许使用不当先验。还提出了边际似然方法与众所周知的信息标准之间的联系。我们通过说明性的数值示例描述了主要问题和可能的解决方案，还提供了一些相关的代码。其中之一涉及外球星的现实应用。

This paper extends quantile factor analysis to a probabilistic variant that incorporates regularization and computationally efficient variational approximations. By means of synthetic and real data experiments it is established that the proposed estimator can achieve, in many cases, better accuracy than a recently proposed loss-based estimator. We contribute to the literature on measuring uncertainty by extracting new indexes of low, medium and high economic policy uncertainty, using the probabilistic quantile factor methodology. Medium and high indexes have clear contractionary effects, while the low index is benign for the economy, showing that not all manifestations of uncertainty are the same.

One of the core problems of modern statistics is to approximate difficult-to-compute probability densities. This problem is especially important in Bayesian statistics, which frames all inference about unknown quantities as a calculation involving the posterior density. In this paper, we review variational inference (VI), a method from machine learning that approximates probability densities through optimization. VI has been used in many applications and tends to be faster than classical methods, such as Markov chain Monte Carlo sampling. The idea behind VI is to first posit a family of densities and then to find the member of that family which is close to the target. Closeness is measured by Kullback-Leibler divergence. We review the ideas behind mean-field variational inference, discuss the special case of VI applied to exponential family models, present a full example with a Bayesian mixture of Gaussians, and derive a variant that uses stochastic optimization to scale up to massive data. We discuss modern research in VI and highlight important open problems. VI is powerful, but it is not yet well understood. Our hope in writing this paper is to catalyze statistical research on this class of algorithms.

离散数据丰富，并且通常作为计数或圆形数据而出现。甚至对于线性回归模型，缀合格前沿和闭合形式的后部通常是不可用的，这需要近似诸如MCMC的后部推理。对于广泛的计数和圆形数据回归模型，我们介绍了能够闭合后部推理的共轭前沿。密钥后和预测功能可通过直接蒙特卡罗模拟来计算。至关重要的是，预测分布是离散的，以匹配数据的支持，并且可以在多个协变量中进行共同评估或模拟。这些工具广泛用途是线性回归，非线性模型，通过基础扩展，以及模型和变量选择。多种仿真研究表明计算，预测性建模和相对于现有替代方案的选择性的显着优势。

Chain event graphs are a family of probabilistic graphical models that generalise Bayesian networks and have been successfully applied to a wide range of domains. Unlike Bayesian networks, these models can encode context-specific conditional independencies as well as asymmetric developments within the evolution of a process. More recently, new model classes belonging to the chain event graph family have been developed for modelling time-to-event data to study the temporal dynamics of a process. However, existing model selection algorithms for chain event graphs and its variants rely on all parameters having conjugate priors. This is unrealistic for many real-world applications. In this paper, we propose a mixture modelling approach to model selection in chain event graphs that does not rely on conjugacy. Moreover, we also show that this methodology is more amenable to being robustly scaled than the existing model selection algorithms used for this family. We demonstrate our techniques on simulated datasets.

预测组合在预测社区中蓬勃发展，近年来，已经成为预测研究和活动主流的一部分。现在，由单个（目标）系列产生的多个预测组合通过整合来自不同来源收集的信息，从而提高准确性，从而减轻了识别单个“最佳”预测的风险。组合方案已从没有估计的简单组合方法演变为涉及时间变化的权重，非线性组合，组件之间的相关性和交叉学习的复杂方法。它们包括结合点预测和结合概率预测。本文提供了有关预测组合的广泛文献的最新评论，并参考可用的开源软件实施。我们讨论了各种方法的潜在和局限性，并突出了这些思想如何随着时间的推移而发展。还调查了有关预测组合实用性的一些重要问题。最后，我们以当前的研究差距和未来研究的潜在见解得出结论。

剩下的交叉验证（LOO-CV）是一种估计样本外预测准确性的流行方法。但是，由于需要多次拟合模型，因此计算LOO-CV标准在计算上可能很昂贵。在贝叶斯的情况下，重要性采样提供了一种可能的解决方案，但是经典方法可以轻松地产生差异是无限的估计器，从而使它们可能不可靠。在这里，我们提出和分析一种新型混合估计量来计算贝叶斯Loo-CV标准。我们的方法保留了经典方法的简单性和计算便利性，同时保证了所得估计器的有限差异。提供了理论和数值结果，以说明提高的鲁棒性和效率。在高维问题中，计算益处尤为重要，可以为更广泛的模型执行贝叶斯loo-CV。所提出的方法可以在标准概率编程软件中很容易实现，并且计算成本大致相当于拟合原始模型一次。

分位数特征选择与相关的多变量时间序列数据一直是一种方法论挑战，是一个公开的问题。在本文中，我们提出了一般的概率方法，用于在分位数特征选择时间序列（QFSTS）模型的名称下进行关节定量时间序列分析中的特征选择。 QFSTS模型是一般的结构时间序列模型，其中每个组件对具有直接解释的时间序列建模产生了添加剂贡献。其灵活性是化合物，用户可以在用户可以为每个次系列添加/扣除组件，并且每个时间序列都可以具有其自身特定的不同大小的价值组件。特征选择是在分位数回归组件中进行的，其中每个时间序列都有自己的同时外部预测器池，允许“垂圈”。通过多变量非对称LAPLACE分布，“峰值板”先前设置，Metropolis-Hastings算法和贝叶斯模型平均技术，开发了创造性的概率方法在扩展到分量时间序列研究区域的特征选择。始终如一地在贝叶斯范式中。与大多数机器学习算法不同，QFSTS模型需要小型数据集训练，快速收敛，并且可在普通的个人计算机上进行可执行。对模拟数据和经验数据的广泛检查确认QFSTS模型具有卓越的性能特征选择，参数估计和预测。

We investigate a general matrix factorization for deviance-based data losses, extending the ubiquitous singular value decomposition beyond squared error loss. While similar approaches have been explored before, our method leverages classical statistical methodology from generalized linear models (GLMs) and provides an efficient algorithm that is flexible enough to allow for structural zeros and entry weights. Moreover, by adapting results from GLM theory, we provide support for these decompositions by (i) showing strong consistency under the GLM setup, (ii) checking the adequacy of a chosen exponential family via a generalized Hosmer-Lemeshow test, and (iii) determining the rank of the decomposition via a maximum eigenvalue gap method. To further support our findings, we conduct simulation studies to assess robustness to decomposition assumptions and extensive case studies using benchmark datasets from image face recognition, natural language processing, network analysis, and biomedical studies. Our theoretical and empirical results indicate that the proposed decomposition is more flexible, general, and robust, and can thus provide improved performance when compared to similar methods. To facilitate applications, an R package with efficient model fitting and family and rank determination is also provided.

We develop an optimization algorithm suitable for Bayesian learning in complex models. Our approach relies on natural gradient updates within a general black-box framework for efficient training with limited model-specific derivations. It applies within the class of exponential-family variational posterior distributions, for which we extensively discuss the Gaussian case for which the updates have a rather simple form. Our Quasi Black-box Variational Inference (QBVI) framework is readily applicable to a wide class of Bayesian inference problems and is of simple implementation as the updates of the variational posterior do not involve gradients with respect to the model parameters, nor the prescription of the Fisher information matrix. We develop QBVI under different hypotheses for the posterior covariance matrix, discuss details about its robust and feasible implementation, and provide a number of real-world applications to demonstrate its effectiveness.

We consider the problem of estimating the interacting neighborhood of a Markov Random Field model with finite support and homogeneous pairwise interactions based on relative positions of a two-dimensional lattice. Using a Bayesian framework, we propose a Reversible Jump Monte Carlo Markov Chain algorithm that jumps across subsets of a maximal range neighborhood, allowing us to perform model selection based on a marginal pseudoposterior distribution of models. To show the strength of our proposed methodology we perform a simulation study and apply it to a real dataset from a discrete texture image analysis.

我们提出了一种新的非参数混合物模型，用于多变量回归问题，灵感来自概率K-Nearthimest邻居算法。使用有条件指定的模型，对样本外输入的预测基于与每个观察到的数据点的相似性，从而产生高斯混合物表示的预测分布。在混合物组件的参数以及距离度量标准的参数上，使用平均场变化贝叶斯算法进行后推断，并具有基于随机梯度的优化过程。在与数据大小相比，输入 - 输出关系很复杂，预测分布可能偏向或多模式的情况下，输入相对较高的尺寸，该方法尤其有利。对五个数据集进行的计算研究，其中两个是合成生成的，这说明了我们的高维输入的专家混合物方法的明显优势，在验证指标和视觉检查方面都优于竞争者模型。

回归模型用于各种应用，为来自不同领域的研究人员提供强大的科学工具。线性或简单的参数，模型通常不足以描述输入变量与响应之间的复杂关系。通过诸如神经网络的灵活方法可以更好地描述这种关系，但这导致不太可解释的模型和潜在的过度装备。或者，可以使用特定的参数非线性函数，但是这种功能的规范通常是复杂的。在本文中，我们介绍了一种灵活的施工方法，高度灵活的非线性参数回归模型。非线性特征是分层的，类似于深度学习，但对要考虑的可能类型的功能具有额外的灵活性。这种灵活性，与变量选择相结合，使我们能够找到一小部分重要特征，从而可以更具可解释的模型。在可能的功能的空间内，考虑了贝叶斯方法，基于它们的复杂性引入功能的前沿。采用遗传修改模式跳跃马尔可夫链蒙特卡罗算法来执行贝叶斯推理和估计模型平均的后验概率。在各种应用中，我们说明了我们的方法如何用于获得有意义的非线性模型。此外，我们将其预测性能与多个机器学习算法进行比较。