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In this study, the authors investigate methods of sequential analysis to test prospectively for the existence of a unit root against stationary or explosive states in a p-th order autoregressive (AR) process monitored over time. Our sequential sampling schemes use stopping times based on the observed Fisher information of a local-to-unity parameter. In contrast to the Dickey–Fuller (DF) test statistic, the sequential test statistic has asymptotic normality. The authors derive the joint limit of the test statistic and the stopping time, which can be characterized using a 3/2-dimensional Bessel process driven by a time-changed Brownian motion. The authors obtain their limiting joint Laplace transform and density function under the null and local alternatives. In addition, simulations are conducted to show that the theoretical results are valid.

Statistical methods of spatial analysis are often successful at either prediction or explanation, but not necessarily both. In a recent paper, Dearmon and Smith (2016) showed that by combining Gaussian Process Regression (GPR) with Bayesian Model Averaging (BMA), a modeling framework could be developed in which both needs are addressed. In particular, the smoothness properties of GPR together with the robustness of BMA allow local spatial analyses of individual variable effects that yield remarkably stable results. However, this GPR-BMA approach is not without its limitations. In particular, the standard (isotropic) covariance kernel of GPR treats all explanatory variables in a symmetric way that limits the analysis of their individual effects. Here we extend this approach by introducing a mixture of kernels (both isotropic and anisotropic) which allow different length scales for each variable. To do so in a computationally efficient manner, we also explore a number of Bayes-factor approximations that avoid the need for costly reversible-jump Monte Carlo methods.

To demonstrate the effectiveness of this Variable Length Scale (VLS) model in terms of both predictions and local marginal analyses, we employ selected simulations to compare VLS with Geographically Weighted Regression (GWR), which is currently the most popular method for such spatial modeling. In addition, we employ the classical Boston Housing data to compare VLS not only with GWR but also with other well-known spatial regression models that have been applied to this same data. Our main results are to show that VLS not only compares favorably with spatial regression at the aggregate level but is also far more accurate than GWR at the local level.

Research into the library as place investigates the role of public library buildings as destinations, physical places where people go for various reasons ranging from making use of the library's resources and services or seeking to fulfill an information or reading need to less easily identified reasons that may include using the library's building as a place to make social or business contacts, to build or reinforce community or political ties, or to create or reinforce a personal identity. This study asks: How are one rural US public library system's newly constructed buildings functioning as places? The answer is derived from answers to sub-questions about adult library users, user, and staff perceptions of library use, and observed use of library facilities. The findings are contextualized using a framework built of theories from human geography, sociology, and information studies.

This case study replicates a mixed-methods case study conducted at the main public libraries in Toronto and Vancouver in the late1990s and first reproduced in Halifax, Nova Scotia in 2006. It tests methods used in large urban settings in a rural, small-town environment. This study also expands on its antecedents by using thematic analysis to determine which conceptualizations of the role of the public library as place are most relevant to the community under investigation.

The study relies on quantitative and qualitative data collected via surveys and interviews of adult library users, interviews of library public service staff members, structured observations of people using the libraries, and analysis of selected administrative documents. The five sets of data are triangulated to answer the research sub-questions.

Thematic analysis grounded in the conceptual framework finds that public realm theory best contextualizes the relationships that develop between library staff members and adult library users over time. The study finds that the libraries serve their communities as informational places and as familiarized locales rather than as third places, and that the libraries facilitate the generation of social capital for their users.

InfoMe is an innovative research program that explores and facilitates how ethnic minority youth help members of their social networks, especially elders, with everyday life situations through information and technology.

The project employs mixed methods, iteratively using Teen Design Days and a stratified random, classroom-based survey (n = 500) in six schools, with multiple community partners in King County, WA.

InfoMe inductively demonstrates how ethnic minority youth help others with situations of daily living through information and technology.

The findings are being used to develop InfoMe applications with the youth and InfoMe Train-the-Trainer workshops for professionals who work with youth.

The research is developing a model of how ethnic minority youth engage as information mediaries in different community settings, how individuals and communities benefit; and it is contributing to our general understanding of specific concepts related to the human information experience.

This chapter presents results of a study that investigated the social information grounds of 45 Māori students ages 16–18 when they are at school.

A mixed research method was used. The quantitative approach was based on a survey questionnaire that was distributed to the students to gather data about their social information behaviour in four schools. The qualitative approach used six focus groups of students to discuss the behaviour.

Māori students exchange, share and seek information within their social networks in six different places in their schools. These places are best described as social information grounds, as defined by Fisher, Naumer, Durrance, Stromski, and Christiansen (2005).

The research identifies the importance that Māori students place on information obtained through interpersonal transactions particularly within their social networks. These social networks play an integral role in assisting Māori students to understand the social and educational environment of which they are part.

This chapter focuses on information grounds and indigenous teenage youth, an understudied area of research. It uses the information grounds theory to explore the social networks of Māori secondary school students in New Zealand.