Statistical models for disaggregation and reaggregation of natural gas consumption data

In this paper, we present a unified framework for natural gas consumption modeling and forecasting. This consists of models of GAM class and their nonlinear extension, tailored for easy estimation, aggregation and treatment of the delayed relationship between temperature and consumption. Since the consumption data for households and small commercial customers are routinely available in many countries only as long-term sum meter readings, their disaggregation and possibly reaggregation to different time intervals is necessary for a variety of purposes. We show some examples of specific models based on the presented framework and then we demonstrate their use in practice, especially for the disaggregation and reaggregation tasks.     

Puerto Rican injection drug users: Prevention implications in Massachusetts and Puerto Rico

This study examines whether place of residence is a factor associated with reporting a positive HIV/AIDS, Hepatitis C (HCV), or Sexually Transmitted Disease (STD) status in a sample of 400 injection drug users (IDUs) residing on the Island of Puerto Rico (N=139) and in western Massachusetts (N=261). Logistic regression models revealed that IDUs residing in western Massachusetts were 66% less likely to be HIV positive compared to IDUs residing in Puerto Rico (p<.000) while IDUs residing in western Massachusetts were about 67% less likely to have a positive STD status than those residing in Puerto Rico (p<.000). Place of residence was not significantly associated with HCV status. Results indicate the need to develop prevention programs tailored to the unique socio-cultural context of Puerto Rican IDUs residing on the Island of Puerto Rico whose circumstances differ from those in the mainland US. To reduce drug use, HIV/AIDS, HCV, and STDs among Puerto Ricans in both locales, the Capacity Enhancement Model is proposed in order to develop more effective prevention programs.     

Are Irrational Beliefs and Depressive Mood More Common Among Problem Gamblers than Non-Gamblers? A Survey Study of Swedish Problem Gamblers and Controls

This study tests the hypothesis that problem gamblers are more prone to have irrational beliefs and depressed mood than non-gamblers. Irrational beliefs refer to fallacious opinions about probabilities. Gamblers like to believe that chance games (i.e., roulette and lottery) can be controlled and that the outcome of such games is dependent on the patterns of previous outcomes. The empirical material consists of responses to a survey that 302 individuals have answered. Half of the respondents were deemed to be problem gamblers. The results showed that compared to the controls, the problem gamblers were more inclined to show illusion of control due to their skill and reported more depressive mood. The results are discussed in terms of difficulties to know the “hen and the egg” regarding depressive mood, and in terms of intermittent reinforcement to continue gambling.     

Athletic involvement and its relevance to hazardous alcohol use and drinking game participation in female college athletes: a preliminary investigation

OBJECTIVE AND PARTICIPANTS: The authors designed this cross-sectional study to examine sports team differences in hazardous alcohol use and drinking game participation, as well as the social correlates of these behaviors among female college athletes (N = 176; M age = 19.9 years, SD = 1.24, range = 18-22). METHODS: Respondents completed self-report surveys in small groups. They reported drinking behaviors, frequency of team social events involving alcohol use, and team cohesion. RESULTS: The authors found significant differences across sports teams with regard to hazardous alcohol use and participation in drinking games with teammates. Findings also revealed that a high frequency of team social events involving alcohol use was associated with elevated use and an increased likelihood of drinking game participation. CONCLUSIONS: The authors discuss future research directions and implications.     

International Migration and the Education of Children: Evidence from Lima,Peru

The issue of whether emigration has consequences for the education of children who remain behind in the country of origin occupies an increasingly prominent place in the agendas of both scholars and policy makers. The conventional wisdom is that the emigration of family members may benefit children by relaxing budget constraints through remittances that can be used to cover educational expenses. However, the empirical evidence on the overall effect of migration is inconclusive. This is due in part to a substantive emphasis on remittances in the literature, as well as the inability of some studies to deal satisfactorily with the endogeneity of household migration decisions in comparing outcomes across migrant and non-migrant households. Using Peruvian data from the Latin American Migration Project (LAMP), we apply an innovative instrumental variable technique to evaluate the overall effect of migration on educational attainment and schooling disruption among the children of immigrants. In contrast to conventional wisdom, our results suggest that a higher household risk of immigration has deleterious consequences for the education of children who remain behind.     

Education as a Positional Good: A Life Satisfaction Approach

In this paper we empirically investigate the direct effects of education on utility. Besides investment aspects of education, the focus is placed on its consumption component and on education positional concerns. We use data from the World Values Survey (WVS) and adopt a life satisfaction approach. First, we find that education shows a significant effect on life satisfaction independent of its effect on income, thus identifying a consumption component of education. Furthermore, given that the contribution of education to individual wellbeing might depend partly on relative position rather than absolute levels, we next study whether education can be considered as a positional good. To this end we analyse the relationship between education and life satisfaction for people in different income groups in which the reference levels of education may differ. Additionally, we control for occupational status since benefits from education could appear via occupational benefits. Our results indicate that the contribution of education to subjective wellbeing is stronger as less people attain a given level of education, thus suggesting that this contribution is partly due to positional concerns.     

Asymptotic hypothesis test to compare likelihood ratios of multiple diagnostic tests in unpaired designs

The accuracy of a binary diagnostic test is usually measured in terms of its sensitivity and its specificity. Other measures of the performance of a diagnostic test are the positive and negative likelihood ratios, which quantify the increase in knowledge about the presence of the disease through the application of a diagnostic test, and which depend on the sensitivity and specificity of the diagnostic test. In this article, we construct an asymptotic hypothesis test to simultaneously compare the positive and negative likelihood ratios of two or more diagnostic tests in unpaired designs. The hypothesis test is based on the logarithmic transformation of the likelihood ratios and on the chi-square distribution. Simulation experiments have been carried out to study the type I error and the power of the constructed hypothesis test when comparing two and three binary diagnostic tests. The method has been extended to the case of multiple multi-level diagnostic tests.     

School counseling practices related to postsecondary STEM participation

This qualitative exploratory cross-case analysis analyzed the beliefs and practices of high school counselors related to science, technology, engineering, and mathematics (STEM) academic advisement, postsecondary planning, and career participation. Interviews were conducted with high school counselors (N = 13) who were purposively sampled to represent a diversity of schools in terms of demographic variables. Findings indicated that high school counselors perceived that (a) sociocultural factors influenced student preparation for STEM, career planning, and decision making; (b) students’ STEM-related career goals and academic behaviors were sometimes misaligned, and academic advisement often mediated this tension; and (c) their professional STEM knowledge, beliefs, and practices were influenced by professional preparation, workplace characteristics, and their academic experiences. Implications include the need for early, sustained high school STEM counseling and academic advisement; accessible professional development in STEM preparation and careers to promote multiple pathways and reduce school counselor bias; and encouraging family involvement in STEM career decision making.     

On Terrel's characterization of uniform distribution

Terrel (1983) (The Annals of Probability, Vol. 11, No. 3, 823–826) showed that the coefficient of correlation between the smaller and larger of a sample of size two is at most one-half, and this upper bound is attained only for continuous uniform distributions. His proof is of computational nature and is based on the properties of Legendre polynomials. We give an easier proof of Terrel's characterization and we show how our method can be used for obtaining sharper bounds within the class of discrete distributions onN points and also a characterization of the equidistant uniform distribution.