The residual effect of a growth-decay mechanism and the distributions of covariance structures

The product of two independent or dependent scalar normal variables, sums of products, sample covariances, and general bilinear forms are considered. Their distributions are shown to belong to a class called generalized Laplacian. A growth-decay mechanism is also shown to produce such a generalized Laplacian. Sets of necessary and sufficient conditions are derived for bilinear forms to belong to this class. As a generalization, the distributions of rectangular matrices associated with multivariate normal random vectors are also discussed.     

英汉思维方式对语言结构的影响

思维方式对语言的结构有哪些影响?本文从形合与意合在句法上与章法上的不同表现,论述了英汉两种语言在结构和表达方式上的不同,并通过实例归纳出一些具体做法,供同行进一步探讨。     

On a Dualization of Graphical Gaussian Models: A Correction Note

Abstract.  We correct two proofs concerning Markov properties for graphs representing marginal independence relations.     

Estimating household structure in ancient China by using historical data: a latent class analysis of partially missing patterns

Summary.  Social data often contain missing information. The problem is inevitably severe when analysing historical data. Conventionally, researchers analyse complete records only. Listwise deletion not only reduces the effective sample size but also may result in biased estimation, depending on the missingness mechanism. We analyse household types by using population registers from ancient China (618–907 AD) by comparing a simple classification, a latent class model of the complete data and a latent class model of the complete and partially missing data assuming four types of ignorable and non-ignorable missingness mechanisms. The findings show that either a frequency classification or a latent class analysis using the complete records only yielded biased estimates and incorrect conclusions in the presence of partially missing data of a non-ignorable mechanism. Although simply assuming ignorable or non-ignorable missing data produced consistently similarly higher estimates of the proportion of complex households, a specification of the relationship between the latent variable and the degree of missingness by a row effect uniform association model helped to capture the missingness mechanism better and improved the model fit.     

完善我国公司治理结构的路径探析

公司治理结构在当代的发展趋势之一是利益相关者共同参与公司治理。我国公司股权集中、内部人控制严重、外部监督机制失灵的治理现状,决定了完善我国公司治理结构的有效路径应是构建利益相关者共同参与的公司治理结构,即将非股东的其他利益相关者引入公司治理,直接参与公司的经营、控制与监督。     

关于中国封建经济结构

中国封建社会虽说是一种农业经济、自然经济,但商品经济却是它不可或缺的润滑剂、催化剂和动力。中国封建社会生产力的基础和主干是个体小生产农业,它要求土地与劳动力的紧密结合,自耕农便成为这种结合的最好形式,能够取得最大的经济效益,而地主土地所有制是以经济的手段与劳动者结合,也能取得较好的经济效益。在农业基础之上的是手工业和商业。城市和货币是中国经济结构涉及的两个特点,而凌驾于这一切之上的,是封建国家对经济的强大的控制与干预。     

Markov Properties for Acyclic Directed Mixed Graphs

We consider acyclic directed mixed graphs, in which directed edges ( x → y ) and bi-directed edges ( x ↔ y ) may occur. A simple extension of Pearl's d -separation criterion, called m -separation, is applied to these graphs. We introduce a local Markov property which is equivalent to the global property resulting from the m -separation criterion for arbitrary distributions.     

An evaluation of the childhood family structure measures from the sixth wave of the British Household Panel Survey

Summary.  The paper performs an evaluation of the data that were collected in the sixth wave of the British Household Panel Survey (BHPS) on childhood family structure. After comparing such data with a large number of studies by using external sources, we find that the BHPS data overestimate the proportion of people who report an experience of life in a non-intact family during childhood by about 10%. Although an explanation based on recall error that deteriorates with the age of the BHPS respondents is possible, the overestimation is likely to be accounted for by non-ignorable attrition that may affect most of the comparison studies based on longitudinal data. Conversely, comparisons with other independent measurements from the BHPS itself reveal that the wave 6 data underestimate the proportion of young people who have lived at least part of their childhood in a non-intact family by about 8%. The probability of disagreement between these two sets of measures is strongly associated with poor interview characteristics, which may affect the comparison measure more than the wave 6 measure. Despite such differences, there is therefore a substantial degree of similarity between the family structure information that was collected in the sixth wave of the BHPS and the host of highly diverse records against which it has been compared.     

The ecosystem blueprint: How firms shape the design of an ecosystem according to the surrounding conditions

Ecosystems are formed by organisations that jointly create a value proposition that a single firm could not create in isolation. To deliver this value proposition, the partners need a focal firm, the orchestrator, to be align them towards the joint value proposition. Thus, how orchestrators design the alignment structure of an ecosystem is at the very heart of the ecosystem concept – yet it has not been sufficiently addressed by extant research. This is all the more true for the question of how the design of an ecosystem is shaped depending on surrounding conditions. This paper applies a qualitative study with ten cases and, based on the attention-based view of the firm, contributes to research on ecosystems in several ways. First, it explains which ecosystem designs are beneficial under which conditions. Second, it elucidates the structure and activities within ecosystems and shows that start-ups can be just as good ecosystem orchestrators as incumbents. Third, it explains the circumstances under which single vs. multi orchestrator ecosystems occur. Fourth, it presents the conditions when incumbents or start-ups make better orchestrators. Finally, it is among the first studies to apply the attention-based view to business ecosystems, and shows that doing so yields intriguing insights into this emerging field of research.     

Family structure and child outcomes in the USA and Sweden

Previous research shows that living in a non-intact family is associated with educational disadvantages. This paper compares the relationships between childhood family structure, schooling, and earnings in Sweden and the USA. This comparison is interesting because both family structure and public policies differ significantly. We find a negative relationship between living in a non-intact family and child outcomes, and the estimates are remarkably similar in both countries. After using sibling-difference models, the correlation with family structure is no longer significant. These results cast doubt on the causal interpretation of the negative relationship between non-intact family structures and child outcomes.