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Network analysis has typically examined the formation of whole networks while neglecting variation within or across networks. These approaches neglect the particular roles actors may adopt within networks. While cross-sectional approaches for inferring latent roles exist, there is a paucity of approaches for considering roles in longitudinal networks. This paper explores the conceptual dynamics of temporally observed roles while deriving and introducing a novel statistical tool, the ego-TERGM, capable of uncovering these latent dynamics. Estimated through an Expectation–Maximization algorithm, the ego-TERGM is quick and accurate in classifying roles within a broader temporal network. An application to the Kapferer strike network illustrates the model's utility.

The highly technical barrier to entry for Big Data and real time analytics has proven to be a hindrance to groups and projects that seek to find insight in large quantities of data or data with a high rate of change. A modular framework that would allow stakeholders to rapidly write and deploy filters to the IBM Infosphere Streams product would provide this level of abstraction and make Big Data technology much easier to implement and use. A common pipeline for data will be developed in tandem to this project in which a simple schema is created. This schema provides a common mechanism to rapidly identify information from a variety of sources of large and changing sets of data. In addition to this common schema, a modular interface implemented using primitive operators will provide a simple API in a common programming language for domain experts to develop filters without the need for a comprehensive understanding of the underlying IBM Infosphere Stream technical details. While a large amount of effort has been applied to make large scale data analysis more expressive and powerful, this has been at the expense of agile development and ease of implementation for non-technical users. The novel nature of this project is to bring a subset of this expressive power with the benefit of ease of use to facilitate rapid and iterative development. This allows domain experts to effectively explore data more quickly. This research project provides value as it abstracts much of the complexity of applying filtering to a rapidly growing and changing set of data. Stakeholders can then implement Big Data and real time analysis rapidly and with technical agility. This notion, whether applied to business intelligence, academia, or government, has tremendous value as it provides a comfortable mechanism to understand data with more clarity.

"The Logics of Systemic Theory" published on by Oxford University Press.

SummaryThe hypothesis that psychological stress during early childhood leads to advanced reproductive maturation was assessed using data from the California Childhood Health and Development Study. Regression analyses failed to indicate that bed wetting, nightmares or thumb-sucking at age 5 predict age at menarche, regardless of controls for mother's age at menarche. Among socioeconomic variables suggested as contextual stressors measured at age 9–11 only mother's education was a significant predictor of daughter's age at menarche, though its effect is trivial compared to mother's age at menarche. Path analysis on a subsample of the subjects failed to demonstrate the hypothesised indirect effect of mother's age at menarche on daughter's age at menarche acting through early marriage and marital dissolution. These results cast doubt on the theory that early childhood stress is the key to divergent reproductive strategies among females based on the timing of reproductive maturation.

SummaryA biosocial model of the effects of early adolescent testosterone levels and religiosity on adolescent males' sexual attitudes and activity over a 3-year period was examined. Using panel data for approximately 100 boys who were 12·5/13·0 years old at study entry, significant additive effects of free testosterone and frequency of attendance at religious services were demonstrated on the transition to first intercourse and other aspects of sexual behaviour and attitudes. No interactive effects of the two predictors were found. Boys with higher free testosterone levels at study entry who never or infrequently attended religious services were the most sexually active and had the most permissive attitudes. Boys with lower free testosterone who attended services once a week or more were the least active and reported the least permissive attitudes. For some behaviours, differences between free testosterone/attendance groups increased over time, resulting in substantial behavioural differences by the final round of measurement 3 years later.

AbstractCentral to the study of Congress is the study of relationships among members. Electoral collaboration is a function of a member's position in the broader congressional power network. It allows members to leverage their campaign resources to achieve the four classic goals of members of Congress: reelection, making good public policy, obtaining power within the institution, and having one's party in the majority. Using nearly 3.2 million FEC records from 2010 to 2016, we explore the dynamics that influence electoral collaboration. We find members are most likely to collaborate electorally with other members from the same state, party, and committee, and the most electorally vulnerable. Further, party leaders share most frequently with the rank and file. These findings build upon our expanding understanding of congressional collaboration, the networks members of Congress form, and the congressional power structure members operate within.

International environmental treaties are the key means by which states overcome collective action problems and make specific commitments to address environmental issues. However, systematically assessing states' influence in promoting global environmental protection has proven difficult. Analyzing newly compiled data with a purpose-built statistical model, we provide a novel measurement of state influence within the scope of environmental politics and find strong influences among states and treaties. Specifically, we report evidence that states are less likely to ratify when states within their region ratify, and results suggesting that countries positively influence other countries at similar levels of economic development. By examining several prominent treaties, we illustrate the complex nature of influence: a single act of ratification can dramatically reshape global environmental politics. More generally, our findings and approach provide an innovative means to understand the evolution and complexity of international environmental protection.