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Summary: This paper introduces a new factor structure suitable for modeling large realized covariance matrices with full likelihood‐based estimation. Parametric and nonparametric versions are introduced. Because of the computational advantages of our approach, we can model the factor nonparametrically as a Dirichlet process mixture or as an infinite hidden Markov mixture, which leads to an infinite mixture of inverse‐Wishart distributions. Applications to 10 assets and 60 assets show that the models perform well. By exploiting parallel computing the models can be estimated in a matter of a few minutes. [ABSTRACT FROM AUTHOR]

In this paper, we study the nth-order nonlinear dynamic equation with Laplacians and a deviating argument [ABSTRACT FROM AUTHOR]

A new optimal back-stepping robust adaptive control method for the military moving power station (MMPS) excitation system is proposed in this paper. Through the extended Kalman filter estimates of the state variables, the tracking of the operating point, and the back-stepping technique, the proposed controller has been shown to improve system robustness to disturbances and dynamic uncertainties and minimise the effect of disturbances by solving the linear matrix inequality to obtain the optimal control law on all operating points. The simulation and experimental results show that the proposed control strategy can enhance the transient stability of the MMPS excitation system more effectively than other methods and can optimise the convergence rates of the state variables by modifying the values of the weighting matrices. Moreover, the terminal voltage of the MMPS can be sampled quickly by alternating current (AC) tracking comparison. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

This paper provides conditions under which the inequality constraints generated by either single agent optimizing behavior or the best response condition of multiple agent problems can be used as a basis for estimation and inference. An application illustrates how the use of these inequality constraints can simplify the analysis of complex behavioral models. [ABSTRACT FROM AUTHOR]

In recent years we have seen a newfound engagement with Jürgen Habermas's work in philosophy of education, focusing on his conception of argumentative dialogue, or discourse, as the origin of both truth‐related epistemic judgments and justifications of moral norms that claim rightness rather than truth. In this article, Krassimir Stojanov first reconstructs the way in which Habermas determines the relation between truth and rightness, and he then shows that moral rightness functions as a "truth‐analogue" since moral norms, like true facts, transcend the actual and local practices of their justification. In the case of moral rightness, this transcendence occurs as an infinite process of inclusion of the perspectives and interests of all potentially concerned persons — also (and foremost) the perspectives and interests of those who are strange to each other in their respective values, worldviews, and interests. With this account of "truth‐analogue" moral rightness, Habermas conceptualizes a kind of processual and "difference‐sensible" universalism, which is very different from the substantialist universalism of some traditional conceptions of education, or Bildung. In the final section, Stojanov shows why including children in their otherness as children in the discursive process of production of moral knowledge, and thus treating them with a kind of epistemic respect, is a constitutive condition for that process. The demand for the discursive inclusion of children follows from the discourse ethics approach, but it requires an enlargement and some corrections of that approach. [ABSTRACT FROM AUTHOR]

We study three preferential attachment models where the parameters are such that the asymptotic degree distribution has infinite variance. Every edge is equipped with a nonnegative i.i.d. weight. We study the weighted distance between two vertices chosen uniformly at random, the typical weighted distance, and the number of edges on this path, the typical hopcount. We prove that there are precisely two universality classes of weight distributions, called the explosive and conservative class. In the explosive class, we show that the typical weighted distance converges in distribution to the sum of two i.i.d. finite random variables. In the conservative class, we prove that the typical weighted distance tends to infinity, and we give an explicit expression for the main growth term, as well as for the hopcount. Under a mild assumption on the weight distribution the fluctuations around the main term are tight. [ABSTRACT FROM AUTHOR]

An explicit form of genus character L‐functions of quadratic orders is presented in full generality. As an application, we generalize a formula due to Hirzebruch and Zagier on the class number of imaginary quadratic fields expressed in term of the continued fraction expansion. [ABSTRACT FROM AUTHOR]

Many real phenomena exhibit non‐Gaussian behavior. The non‐Gaussianity is manifested by impulsive behavior of the real data that can be found in both one‐dimensional and multi‐dimensional cases. Especially the multi‐dimensional datasets with non‐Gaussian behavior pose substantial analysis challenges to scientists and statisticians. In this article, we analyze the bidimensional vector autoregressive (VAR) model based on general bidimensional α‐stable distribution. This time series can be applied in modeling bidimensional data with impulsive behavior. We focus on the description of the spatio‐temporal dependence for analyzed bidimensional time series which in the considered case cannot be expressed in the language of the classical cross‐covariance or cross‐correlation function. We propose a new cross measure based on the alternative measure of dependence adequate for infinite variance processes, namely cross‐covariation. This article is an extension of the authors' previous work where the cross‐codifference was considered as the spatio‐temporal measure of the components of VAR model based on sub‐Gaussian distribution. In this article, we demonstrate that cross‐codifference and cross‐covariation can give different information about the relationships between components of bidimensional VAR models. [ABSTRACT FROM AUTHOR]

The viability of a switched system on a bounded polyhedron set, which is expressed by some linear inequalities, is investigated. Based on nonsmooth analysis and the properties of the tangent cone, a necessary and sufficient condition for viability is proposed. It is shown that the viability of a system is equivalent to the consistency of some systems of linear inequalities. Specifically, a viability condition for a switched system on a bounded polyhedron is presented. According to this condition, determining the viability of a bounded polyhedron can be transformed into verifying certain conditions at vertices of each facet. The method of determining viability, which transforms verifying the condition from infinite points to finite ones, can be implemented easily in practice. An algorithm to determine the viability for the switched system is constructed by using convex analysis. In addition, the approach can be extended to the switched system in which a control input is present. Finally, an example is listed to illustrate the effectiveness of the results. [ABSTRACT FROM AUTHOR]

We consider a model of infinite dimensional differential variational inequalities formulated by a parabolic differential inclusion and an elliptic variational inequality. The existence of global solution and global attractor for the semiflow governed by our system is proved by using measure of noncompactness. Copyright © 2017 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Confidence intervals are commonly used to describe parameter uncertainty. In nonstandard problems, however, their frequentist coverage property does not guarantee that they do so in a reasonable fashion. For instance, confidence intervals may be empty or extremely short with positive probability, even if they are based on inverting powerful tests. We apply a betting framework and a notion of bet-proofness to formalize the 'reasonableness' of confidence intervals as descriptions of parameter uncertainty, and use it for two purposes. First, we quantify the violations of bet-proofness for previously suggested confidence intervals in nonstandard problems. Second, we derive alternative confidence sets that are bet-proof by construction. We apply our framework to several nonstandard problems involving weak instruments, near unit roots, and moment inequalities. We find that previously suggested confidence intervals are not bet-proof, and numerically determine alternative bet-proof confidence sets. [ABSTRACT FROM AUTHOR]

We propose and analyze the finite volume method for solving the variational inequalities of first and second kinds. The stability and convergence analysis are given for this method. For the elliptic obstacle problem,we derive the optimal error estimate in the H1-norm. For the simplified friction problem,we establish an abstract H1-error estimate, which implies the convergence if the exact solution u ϵ H1(Ω) and the optimal error estimate if u ϵ H11+α(Ω)0 < ⩽ 2. [ABSTRACT FROM AUTHOR]

We study properties of the distribution [ABSTRACT FROM AUTHOR]