On Tail Index Estimation based on Multivariate Data

This article is devoted to the study of tail index estimation based on i.i.d. multivariate observations, drawn from a standard heavy-tailed distribution, i.e. of which 1-d Pareto-like marginals share the same tail index. A multivariate Central Limit Theorem for a random vector, whose components correspond to (possibly dependent) Hill estimators of the common shape index alpha, is established under mild conditions. Motivated by the statistical analysis of extremal spatial data in particular, we introduce the concept of (standard) heavy-tailed random field of tail index alpha and show how this limit result can be used in order to build an estimator of alpha with small asymptotic mean squared error, through a proper convex linear combination of the coordinates. Beyond asymptotic results, simulation experiments illustrating the relevance of the approach promoted are also presented

Sloshing in the LNG shipping industry: risk modelling through multivariate heavy-tail analysis

In the liquefied natural gas (LNG) shipping industry, the phenomenon of sloshing can lead to the occurrence of very high pressures in the tanks of the vessel. The issue of modelling or estimating the probability of the simultaneous occurrence of such extremal pressures is now crucial from the risk assessment point of view. In this paper, heavy-tail modelling, widely used as a conservative approach to risk assessment and corresponding to a worst-case risk analysis, is applied to the study of sloshing. Multivariate heavy-tailed distributions are considered, with Sloshing pressures investigated by means of small-scale replica tanks instrumented with d >1 sensors. When attempting to fit such nonparametric statistical models, one naturally faces computational issues inherent in the phenomenon of dimensionality. The primary purpose of this article is to overcome this barrier by introducing a novel methodology. For d-dimensional heavy-tailed distributions, the structure of extremal dependence is entirely characterised by the angular measure, a positive measure on the intersection of a sphere with the positive orthant in Rd. As d increases, the mutual extremal dependence between variables becomes difficult to assess. Based on a spectral clustering approach, we show here how a low dimensional approximation to the angular measure may be found. The nonparametric method proposed for model sloshing has been successfully applied to pressure data. The parsimonious representation thus obtained proves to be very convenient for the simulation of multivariate heavy-tailed distributions, allowing for the implementation of Monte-Carlo simulation schemes in estimating the probability of failure. Besides confirming its performance on artificial data, the methodology has been implemented on a real data set specifically collected for risk assessment of sloshing in the LNG shipping industry

Seat of Choice: The Advantages of Flexible Seating

The focus of this Capstone Project is the advantages of Flexible Seating. This is important because students thrive off of choice in the classroom and Flexible Seating offers many ways for a student’s success. It is argued that teachers should implement Flexible Seating because of the increase in collaboration, student engagement, and overall success. The primary stakeholder perspective chosen was a veteran teacher who has implemented Flexible Seating and their fifth grade class, this is because of their experiences with this classroom design. Three themes emerged from an analysis of the data and were explored as ways to address the issue presented. Based on an analysis of the interviews and the relevant research literature, the researcher used what they learned to formulate an action that responded in a way that inspires, informs, or involves a particular audience

Redefining Women's Work: Female Entrepreneurs on the South Side of Indianapolis, 1880-1920

Indiana University-Purdue University Indianapolis (IUPUI)Research on the roles of women in the past commonly focuses on either the demure or the radical. This study of female entrepreneurs shows an area in which women occupied a more central position in their communities. Female entrepreneurs were able to possess a certain degree of independence without being viewed, or viewing themselves, as rebellious. This thesis focuses exclusively on the women who owned businesses on a two-block length of one street, South Meridian, in Indianapolis, over a forty-year period. Even with this limited focus, there is substantial variation in the motivations of the women. Some entered in to business with the support of their wealthy families, while others were obligated to work to support their families. The stories of these women can be revealed through their presence in official documents, city directories, and newspapers of the time. In addition to the individual stories of female entrepreneurs, these sources provide information about who the businesswomen of the time were as a group. The majority were born in the United States and among that group most were born in the state of Indiana. The most common businesses owned by women were millinery shops, dress shops, and boarding houses. Other demographic characteristics, such as age, marital status, and time in business, do not form a pattern across the group. These sources also show how women compared to men who were in business in the same location over the same period. Most of the female entrepreneurs of the South Side of Indianapolis around the turn of the century worked in fields that could fit under the heading of “women’s work,” but this categorization ignores the intricacies of their positions as business people. These women were not solely providing a service or producing a good, similar to what they would be expected to do in the home as wives, mothers, or daughters. They were also responsible for the other aspects of business ownership, including finding and maintaining premises, purchasing products and materials, and managing finances. It is these details that, for example, set apart the owner of a dress shop from a woman making clothes for her family

Clinical assessment of the infant and child following perinatal brachial plexus injury.

STUDY DESIGN: Literature review. INTRODUCTION: After perinatal brachial plexus injury (PBPI), clinicians play an important role in injury classification as well as the assessment of recovery and secondary conditions. Early assessment guides the initial plan of care and influences follow-up and long-term outcome. PURPOSE: To review methods used to assess, classify and monitor the extent and influence of PBPI with an emphasis on guidelines for clinicians. METHODS: We use The International Classification of Functioning, Disability, and Health (ICF) model to provide a guide to assessment after PBPI for rehabilitation clinicians. DISCUSSION: With information gained from targeted assessments, clinicians can design interventions to increase the opportunities infants and children have for optimal recovery and to attain skills that allow participation in areas of interest