U-statistics generalizes the concept of mean of independent identically distributed (i.i.d.) random variables and is widely utilized in many estimating and testing problems. The standard empirical likelihood (EL) for U-statistics is computationally expensive because of its onlinear constraint. The jackknife empirical likelihood method largely relieves computation burden by circumventing the construction of the nonlinear constraint. In this thesis, we adopt a new jackknife empirical likelihood method to make inference for the general volume under the ROC surface (VUS), which is one typical kind of U-statistics. Monte Carlo simulations are conducted to show that the EL confidence intervals perform well in terms of the coverage probability and average length for various sample sizes.

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In the early 1990s Graham Nuthall and Adrianne Alton-Lee developed a model of the learning and remembering process which has profound implications for teaching and learning at all levels. Using their model they were able to predict what selected primary school students would and would not learn and remember from the teaching of a series of Science and Social Studies units and to do so with an accuracy of between 80 to 85 per cent. The Nuthall model states that for a student to learn and remember a new fact or concept he or she needs three to four learning opportunities with the complete set of information needed to learn the new fact or concept, and a gap of no more than two days between any pair of those two learning opportunities. It had always been Graham Nuthall's intention to test the model he developed with Adrienne Alton-Lee in a series of experiments. Tragically, Professor Graham Nuthall died before this was possible. The ten experiments in this thesis put the Nuthall model to the test.

Service screening with mammography was implemented in Northern Sweden between 1989 and 1998, covering 190,000 women aged 40-74 years constituting the target population in the area. The aim of this thesis was the evaluation of mammography screening in Northern Sweden with special focus on selected screening performance indicators and on the disease outcome. We analysed interval cancer (IC) incidence and episode sensitivity in the Norrbotten Mammography Screening Programme (NMSP) for the period 1989-2002. An overall IC rate at 1.1/1000 and IC rate ratio at 38% was found and epsiode sensitivity was estimated at 62-73%, in concert with reference values of the European guidelines. Radiological classification of the IC cases in three rounds of the NMSP showed that true, occult, missed and minimal signs IC, were present in 48%, 10%, 14% and 28% of the cases. We analysed early death from breast cancer (n=342) in Northern Sweden during the first five years of mammography service screening. Most fatal cases were advanced and incurable on diagnosis. In a few screen-detected cases with favourable prognostic factors the fatal outcome was unexpected. We estimated breast cancer survival by detection mode in 5120 women with breast cancer. We found a significantly favourable survival among IC cases compared to cases among uninvited. We studied breast cancer mortality in relation to mammography screening. Our findings indicated a long-term reduction of breast cancer mortality by 26-30% among women invited to screening and by 31-35% among women screened compared to not screened. We conclude from our evaluation of the mammography screening in Northern Sweden that women benefited from this public health intervention in form of improved survival and reduced mortality.

The maintenance of equipment has been an important issue for companies for many years. For systems with hidden or unrevealed failures (i.e., failures are not self-announcing), a common practice is to regularly inspect the system looking for such failures. Examples of these systems include protective devices, emergency devices, standby units, underwater devices etc. If no periodical inspection is scheduled, and a hidden failure has already occurred, severe consequences may result. Research on periodical inspection seeks to establish the optimal inspection interval (Failure Finding Interval) of systems to maximize availability and/or minimize expected cost. Research also focuses on important system parameters such as unavailability. Most research in this area considers non-negligible downtime due to repair/replacement but ignores the downtime caused by inspections. In many situations, however, inspection time is non-negligible. We address this gap by proposing an optimal failure finding interval (FFI) considering both non-negligible inspection time and repair/replacement time. A novel feature of this work is the development of models for both age-based and calendar-based inspection policies with random/constant inspection time and random/constant repair/replacement time. More specifically, we first study instantaneous availability for constant inspection and repair/replacement times. We start with the assumption of renewal of the system at each inspection. We then consider models with the assumption of renewal only after failure. We also develop limiting average availability models for random inspection and repair/replacement times, considering both age-based and calendar-based inspection policies. We optimize these availability models to obtain an optimal FFI in order to maximize the system’s availability. Finally, we develop several cost models for both age-based and calendar-based inspection policies with random inspection time and repair/replacement time. We formulate the model for constant inspection time and repair/replacement time as a special case. We investigate the optimization of cost models for each case to obtain optimal FFI in order to minimize the expected cost. The numerical examples and case study presented in the dissertation demonstrate the importance of considering non-negligible downtime due to inspection.

The maintenance of equipment has been an important issue for companies for many years. For systems with hidden or unrevealed failures (i.e., failures are not self-announcing), a common practice is to regularly inspect the system looking for such failures. Examples of these systems include protective devices, emergency devices, standby units, underwater devices etc. If no periodical inspection is scheduled, and a hidden failure has already occurred, severe consequences may result. Research on periodical inspection seeks to establish the optimal inspection interval (Failure Finding Interval) of systems to maximize availability and/or minimize expected cost. Research also focuses on important system parameters such as unavailability. Most research in this area considers non-negligible downtime due to repair/replacement but ignores the downtime caused by inspections. In many situations, however, inspection time is non-negligible. We address this gap by proposing an optimal failure finding interval (FFI) considering both non-negligible inspection time and repair/replacement time. A novel feature of this work is the development of models for both age-based and calendar-based inspection policies with random/constant inspection time and random/constant repair/replacement time. More specifically, we first study instantaneous availability for constant inspection and repair/replacement times. We start with the assumption of renewal of the system at each inspection. We then consider models with the assumption of renewal only after failure. We also develop limiting average availability models for random inspection and repair/replacement times, considering both age-based and calendar-based inspection policies. We optimize these availability models to obtain an optimal FFI in order to maximize the system’s availability. Finally, we develop several cost models for both age-based and calendar-based inspection policies with random inspection time and repair/replacement time. We formulate the model for constant inspection time and repair/replacement time as a special case. We investigate the optimization of cost models for each case to obtain optimal FFI in order to minimize the expected cost. The numerical examples and case study presented in the dissertation demonstrate the importance of considering non-negligible downtime due to inspection.

It has been shown that a high level of aerobic fitness is important for athletes participating in intermittent (team) sports. The majority of studies investigating the effects of traditional and sport-specific aerobic interval exercise on physiological measures and performance have involved field-based team sports. In some instances the effectiveness of sport-specific aerobic training has been questioned. To date, no study has investigated the influence of a sport-specific training approach in the sport of basketball. Purpose: The aim of the present study was to evaluate the effectiveness of a basketball specific endurance circuit on improving measures of aerobic fitness. Methods: Ten male high school basketball players, age 16.4 ± 1.2 years, ranked by fitness level and randomly assigned to a training group (N = 6) or control group (N = 4) participated in the study. The sport-specific aerobic endurance training replaced the fitness component of regular training and was performed during the competitive season. The sport-specific training consisted of interval training using a basketball specific endurance circuit, four times 4 min at 90-95% HRpeak with a 3 min recovery at 60-70% HRpeak, twice per week for 6 weeks. During this time the control group performed regular basketball training. Results: For both the training and control groups the actual mean training intensity for total training duration were 77.4 ± 2.9% HRpeak and 74.1 ± 6.7% HRpeak, respectively. The actual mean training intensity during the work intervals in the training group was 84.1 ± 2.3% HRpeak. There were no clear differences between effects of the two training approaches for measures of maximal oxygen uptake (3.3%; 90% confidence limits, ± 19.3%), running economy (-3.3%; 90% confidence limits, ± 14.2%), repeated sprint ability (0.6%; 90% confidence limits, ± 5.7%) and anaerobic power maintenance during the repeated sprints (-13.7%; 90% confidence limits, ± 49.0%). However, a clear non-trivial effect on sub-maximal heart rate was observed (-7.3%; 90% confidence limits, ± 2.0%) suggesting a beneficial training effect after training. Some evidence for attenuation of speed (-1.8 to -2.8%; 90% confidence limits, ± 3.4 to 5.7%) and power (-1.7%; 90% confidence limits, ± 17.1%) was apparent. Conclusion: Although clear changes in sub-maximal HR responses were observed in the training group, the data in the present study suggests that a basketball specific endurance circuit has little effect on other laboratory and field-based measures of aerobic fitness. In fact, the basketball specific endurance circuit may lead to reduced improvements in jumping and sprinting performances. Further research is required to clarify the effect of aerobic training approaches on basketball-specific fitness and performance.

The purpose of this study was to assess the efficacy of two different modes of exercise in an overweight and obese population over a 12-week period. Subjects: Forty-four overweight or obese individuals were recruited from a weight loss organisation. Participants were randomised into one of two groups which were matched according to age, gender and body mass index (BMI). The interventions consisted of either intermittent interval exercise (INT group), or intermittent steady-state exercise (SS group). Participants in both groups were on an identical strict caloric diet during the intervention period. Methods: Baseline and post-intervention testing consisted of the assessment of aerobic fitness, blood lipid profile, resting metabolism, body composition, vascular function, quality of life and activity levels. The exercise regime for the INT group consisted of a 1:2 min ratio of moderate intensity (70 75% V&O2peak) to low intensity exercise (40 45% V&O2peak), while the SS group exercised continuously between 50 55% V&O2peak. Total work per session was the same per group. Exercise consisted of walking/jogging twice daily for 15 mins five days per week. Eighteen participants dropped out of the study leaving 12 in the INT group and 14 in the SS group. Results: Peak oxygen uptake and exercise time to exhaustion increased significantly over time in the interventions (P < 0.001). Significant positive changes occurred in several blood tests, including liver function, insulin like growth factor (IGF- 1) and lipid levels (cholesterol, triglyceride, low density lipoprotein (LDL) and very low density lipoprotein (VLDL) and coronary risk ratio, all P < 0.05 over time). Additionally, uric acid and VLDL levels significantly decreased over time in the SS and INT groups, respectively (P < 0.05), whereas IGF-1 levels significantly increased in the SS group over time (P < 0.05). Body composition measures, including BMI, body mass, fat mass, percent of body fat, gynoid obesity and hip circumference, as well as waist circumference decreased significantly over time (P < 0.05). Several components of the SF-36 quality of life questionnaire (physical function, role physical, bodily pain, general health, vitality, social function and mental health) improved significantly over time (P < 0.05), while mental health also significantly improved over time in the SS group (P < 0.01). Finally, anxiety and depression levels were significantly reduced over time (P < 0.05). However, none of these changes over time significantly differed between the two groups. Conclusion: Both exercise interventions resulted in significant improvement over time in numerous health and fitness variables in an overweight and obese population. No significant differences were found, in the interaction term during a 2-way ANOVA, between the two groups at post-intervention. A longer intervention period, or changes to interval duration and intensities may result in more significant differences between the two training methods.

Thesis (M.S.)--University of Missouri--Rolla, 2007. / Vita. The entire thesis text is included in file. Title from title screen of thesis/dissertation PDF file (viewed March 27, 2008) Includes bibliographical references (p. 86-89).

Thesis (Ph. D.)--University of Missouri-Columbia, 2004. / Typescript. Vita. Includes bibliographical references (leaves 46-54). Also available on the Internet.