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At Wake Forest University, a student who is blind enrolled in a second course in statistics. The course covered simple and multiple regression, model diagnostics, model selection, data visualization, and elementary logistic regression. These topics required that the student both interpret and produce three sets of materials: mathematical writing, computer programming, and visual displays of data. While we did find scattered resources for blind students taking mathematics courses or introductory statistics courses, we found no complete account of teaching statistical modeling to students who are blind. We also discovered some challenges in stitching together multiple partial solutions. This paper outlines our specific approach. We relied heavily on integrating the use of multiple existing technologies. Specifically, this paper will detail the extensive use of screen readers, LATEX, a modified use of R and the BrailleR package, a desktop Braille embosser, and a modified classroom approach.

Technology Engineering is an innovative component of a much larger arena of teaching that effectively uses interactive technology as a method of enhancing learning and the learning environment. Using this method to teach science and math content empowers the teacher and enhances the curriculum as the classroom becomes more efficient and effective. Although the most modern technology--enhanced content is available for classroom deployment, this study suggests that various challenges arise that can delay a fully productive and successful integration of technology in the science classroom. In this study, seven urban school science teachers, incorporated technology-enhanced inquiry-based modules into their lesson plans to determine the overall effectiveness of technology integration in their classrooms. This paper examines how Technology Engineering helps students to understand scientific phenomena, despite hindrances within the instructional environment.

In 2009, the North Carolina Community College System (NCCCS) began the process of redesigning developmental mathematics (DMA) courses. The first classes were offered in 2012 with final state implementation in fall 2013. The purpose of this study was to examine the subsequent gateway course success rates achieved by former DMA students in relation to the delivery method (i.e., teacher-centered, student-centered, and computer-centered) used in the redesigned North Carolina DMA courses. Students included in this study took a gateway math course and a developmental math course during the same or previous academic year. Students who participated in student-centered and computer-centered instruction in their DMA course had a statistically significant pass rate in subsequent gateway courses compared with students receiving teacher-centered instruction. Along with the findings, this paper discusses considerations for redesign, including the choice of delivery methods and instructional techniques, and recommendations for further research.

In a recidivism prediction context, there is no consensus on which modeling strategy should be followed for obtaining an optimal prediction model. In previous papers, a range of statistical and machine learning techniques were benchmarked on recidivism data with a binary outcome. However, two important tree ensemble methods, namely gradient boosting and random forests were not extensively evaluated. In this paper, we further explore the modeling potential of these techniques in the binary outcome criminal prediction context. Additionally, we explore the predictive potential of classical statistical and machine learning methods for censored time-to-event data. A range of statistical manually specified statistical and (semi-)automatic machine learning models is fitted on Dutch recidivism data, both for the binary outcome case and censored outcome case. To enhance generalizability of results, the same models are applied to two historical American data sets, the North Carolina prison data. For all datasets, (semi-) automatic modeling in the binary case seems to provide no improvement over an appropriately manually specified traditional statistical model. There is however evidence of slightly improved performance of gradient boosting in survival data. Results on the reconviction data from two sources suggest that both statistical and machine learning should be tried out for obtaining an optimal model. Even if a flexible black-box model does not improve upon the predictions of a manually specified model, it can serve as a test whether important interactions are missing or other misspecification of the model are present and can thus provide more security in the modeling process. [ABSTRACT FROM AUTHOR]

National reports have documented deficiencies in the vertical alignment of mathematical learning in K-12 education. Many students fail to master requisite concepts before advancing to more complex ideas, leaving them ill-prepared to succeed in higher level Science, Technology, Engineering, and Mathematics (STEM) coursework. In this paper, we model elementary and middle school students’ performance in mathematics over time as a stochastic process to forecast their proficiency by the eighth grade. We conduct an extensive examination of tens of thousands of student records and extract useful information. We use this data to present a longitudinal analysis of student performance on the North Carolina End-of-Grade mathematics exam and use Markov chain models to probabilistically characterize the movement of students’ scores from one grade level to the next. This work is the first step in developing a framework to forecast individual students’ development of mathematical knowledge over time. [ABSTRACT FROM AUTHOR]

Background: Concurrent sexual partnerships (partnerships that overlap in time) may contribute to higher rates of HIV transmission in African Americans. Attitudes toward a behavior constitute an important component of most models of health-related behavior and behavioral change. We have developed a scale, employing realistic vignettes that appear to reliably measure attitudes about concurrency in young African American adults. Methods: Vignette-based items to assess attitudes about concurrency were developed following focus groups and cognitive testing of items adapted from existing scales assessing psychosocial constructs surrounding related sexual behaviors. The new items were included in a telephone survey of African American adults (18–34 years old) in Eastern North Carolina immediately before and after a radio campaign designed to discourage concurrency. We performed an exploratory factor analysis on each sample (pre- and post-campaign) to cross-validate results. We retained factors with a primary loading of ≥0.50 and no secondary loading >0.30. Cronbach’s coefficient alpha was used to evaluate internal reliability. Associations in the predicted direction between the mean responses to items on the final factor and known correlates of concurrency validated the scale. Results: Factor analysis in a random pre-campaign subsample yielded a one-factor 6-item scale with acceptable internal consistency (Cronbach’s α = 0.79). As expected, the attitude factor was positively associated with participation in concurrent partnerships, whether assessed by self-report (r = 0.298, p<0.0001) or deduced from dates of recent sexual partnerships (r = 0.298, p<0.0001). The factor was also positively associated with alcohol (r = 0.216, p<0.0001) and drug use (r = 0.225, p<0.0001) and negatively associated with increasing age (r = -0.088, p- = 0.02) and female gender (r = -0.232, p<0.0001). Factor analyses repeated in the second random pre-campaign subsample and post-campaign sample confirmed these results. Conclusion: A vignette-based scale may be an effective measure of key attitudes related to concurrency and potentially a useful tool to evaluate interventions addressing this network pattern. [ABSTRACT FROM AUTHOR]

The article discusses research which was conducted to investigate the magnitude of dehydration and acute weight gain in mixed martial arts fighters before a competition. Researchers evaluated 40 fighters. They found that on average the fighters gained 4.4% of their body weight before a competition and that 39% appeared to have significant or serious dehydration.

This study investigated within group differences between African American female and male students who participated in the 2009 National Assessment of Educational Progress mathematics assessment. Using results from participating states, we compare average scale scores of African American students based on home regulatory environment and interest in mathematics. Results indicated that African American male students who discussed studies 2-3 times a week scored higher than African American female students who discussed studies every day. In three states (Connecticut, Florida, and New Jersey), African American males who never or hardly ever discussed studies at home scored higher than African American males who never or hardly ever discussed studies at home in the state of Arkansas. In two states (Florida and New Jersey), African American males who discussed studies every few weeks scored higher than African American males who discussed studies every few weeks in Arkansas. In four states (Connecticut, Florida, Illinois, and New Jersey), the overall scale scores of African American males was higher than those of African American males in Arkansas. As a result of the findings, we present practical implications for parents of African American students. [ABSTRACT FROM AUTHOR]

Javelin throwing is technically demanding. Sequences of upper and lower extremity motions are important for javelin throwing performance. The purpose of this study was to determine the general sequences of upper and lower extremity motions of elite male and female javelin throwers. Three-dimensional kinematic data were collected for 32 female and 30 male elite javelin throwers during competitions. Shoulder, elbow, wrist, hip, knee, ankle, lower trunk, and upper trunk joint and segment angles were reduced for the best trial of each participant. Beginning times of 6 upper extremity and 10 lower extremity joint and segment angular motions were identified. Sequences of the upper and lower extremity motions were determined through statistical analyses. Upper and lower extremity motions of the male and female elite javelin throwers followed specific sequences (P ≤ 0.050). Upper extremity motions of the male and female elite javelin throwers did not follow a proximal-to-distal sequence as suggested in the literature. Male and female elite javelin throwers apparently employed different sequences for upper and lower extremity motions (P < 0.001). Further studies are needed to determine the effects of sequences of upper and lower extremity motions on javelin throwing performance. [ABSTRACT FROM AUTHOR]

Background: Chronic disease prevalence amongst Canadian Arctic populations is increasing, but the literature amongst Inuvialuit is limited. The present study aimed to provide baseline data that could be used to monitor changes in chronic disease risk factors and long-term health in the Arctic by determining prevalence and risk factors of self-reported chronic disease amongst adult Inuvialuit in remote communities. Methods: Self-reported demographics and history of chronic disease (hypertension, heart disease, diabetes and cancer) were collected in three communities between July 2007 and July 2008 in the Northwest Territories. Food frequency questionnaires recorded dietary intake, International Physical Activity Questionnaires recorded physical activity and anthropometric measures of height and weight were obtained. Results: Response rates ranged from 65–85%. More than 20% of the 228 participants aged 19–84 years reported having a chronic disease. Age-adjusted prevalence was 28, 9, 9 and 6 per 100 for hypertension, heart disease, diabetes and cancer, respectively. Compared with non-cases, participants reporting hypertension were more likely to have a higher body mass index and a lower level of education. Hypertension was more common amongst participants reporting heart disease and diabetes than Inuvialuit not reporting these morbidities. Conclusions: Inuvialuit participants in this study were most affected by hypertension and diabetes compared with heart disease or any cancer. Female participants had a higher prevalence of heart disease compared with the Canadian average. Primary preventive strategies are necessary to mitigate the increasing rates of chronic disease risk factors in this population. Further studies with a larger sample size and measured chronic disease are necessary to confirm the findings obtained in the present study. [ABSTRACT FROM AUTHOR]

Background: Validation of a quantitative food frequency questionnaire (QFFQ) developed specifically for Inuit is necessary to determine its usefulness in assessing dietary intake and adequacy and in identifying dietary risk factors for chronic disease in this population. Methods: Seventy-five randomly selected Inuit adults in Nunavut, Canada, were recruited. Mean daily intake of nutrients from one to three 24-h recalls was used as the reference to measure QFFQ validity. Crude and energy-adjusted Spearman rank correlations (ρ), cross classification and weighted kappa were computed as measures of concordance. Bland–Altman plotting was used for additional assessment. Results: Excluding four participants with daily energy intake of >25.1 MJ, 71 participants were included in the analysis. For all nutrients, mean daily intake from the QFFQ was higher than the recall. ρ’s for macronutrients were in the range 0.71 for carbohydrate to 0.25 for protein. The best ρ amongst micronutrients was observed for vitamin C (0.66). Overall correlation between the two dietary tools improved after correction for within-person variance (from 0.46 to 0.49), although adjusting for energy did not improve the overall coefficient. When nutrient intakes were categorised into quartiles, the QFFQ and 24-h recalls indicated relative agreement proportion (same or adjacent quartiles) of 83% for energy, 94% for total sugar, 83% for macronutrients and 77% for micronutrients. Bland–Altman plots showed a tendency for increased scatter of the differences in nutrients at higher intakes. Conclusions: The QFFQ developed is valid and can be used to assess usual dietary intake and dietary adequacy, determine the contribution of foods to specific nutrient intakes, and identify dietary risk factors for chronic disease amongst this population. [ABSTRACT FROM AUTHOR]

Background: The estimation of dietary intake in population-based studies is often assessed by a food frequency questionnaire (FFQ). This present study aimed to establish the validity of a 142-item quantitative FFQ (QFFQ) developed to assess dietary intake in a population living in the Northwest Territories, Canada, and undergoing rapid nutrition transition. Methods: Sixty-four randomly selected Inuvialuit adults were recruited. The mean of one to three 24-h recalls was used as the reference to measure the validity of the QFFQ. Spearman rank correlations (ρ), cross-classification and weighted kappa were computed as measures of concordance, adjusting for the daily dietary intake variations in the recalls. Bland – Altman plots were used for additional assessment. Results: Four participants with daily energy intake of >25.1 MJ were not included in the analysis. For all nutrients, mean daily intake estimations were higher from the QFFQ than from the recalls. De-attenuated ρ’s for macronutrients ranged from 0.33 (protein) to 0.45 (carbohydrate). The best de-attenuated ρ amongst micronutrients was observed for vitamin C (0.53). Overall correlation between the two dietary tools improved after correction for within-person variance (from 0.32 to 0.35). When nutrient intakes were categorised into quartiles, the QFFQ and 24-h recalls indicated relative agreement (same or adjacent quartiles) for 77% for energy and macronutrients, 86% for total sugar and 72% for micronutrients. Bland–Altman plots showed a tendency for increased scatter of the differences at higher intakes. Conclusions: The QFFQ developed is valid and can be used to assess usual dietary intake and dietary adequacy, determine the contribution of foods to specific nutrient intakes, and identify dietary risk factors for chronic disease amongst Inuvialuit. [ABSTRACT FROM AUTHOR]

A lethal defect-wear model of mortality is presented which rationalizes the assumption of independent risks when death may be due to more than a single condition. Under this model, it is shown how competing risk theory and standard categorical data methods may be merged in a unified approach to the analysis of multiple-cause mortality data. The methodology is used to analyze linkages among diseases in the mortality data and evaluate the implication of the elimination of patterns of morbid states for multiple-cause mortality data from deaths occurring in 1969 in North Carolina. [ABSTRACT FROM AUTHOR]