The goal of the research project was to assess the effect of a written intervention on the state anxiety of new mathematics teachers. Twenty-eight beginning mathematics teachers in Washington, Oregon, and California were randomly assigned to treatment or control groups. Treatment was a survival guide, Green Broke, carefully designed to meet the needs of beginning mathematics teachers. A Delphi panel determined topics for the guide, beginning with suggestions from the literature. The panel included mathematics teachers in grades 7 to 12 from all three Pacific states, and both urban and rural areas. School administration and college mathematics education were also represented on the panel. A subset of the panel and a writer edited the guide. Trait anxiety of subjects was determined prior to the 1989-90 school year using the trait anxiety portion of Spielberger's State-Trait Anxiety Inventory. The state anxiety inventory was administered at that same time and again three times during the school year. All subjects also completed a teacher report twice during the year regarding their teaching experiences. In addition, the treatment group was asked to complete two questionnaires regarding the effectiveness of Green Broke. Subjects perceived that they were part of two studies, one involving the guide and one involving anxiety inventories. Analysis of covariance for repeated measures was used to assess differences between groups in state anxiety, using trait anxiety as covariate. Level of significance was set at .05. There was no significant main effect, but a significant interaction effect was found. The nearly linear relationship between state and trait anxiety found in the control group disappeared for the group having the guide. Mini case studies, using responses to the teacher reports, were done for seven subjects, including those with very high state anxiety. In addition, a subgroup of the treatment group, for which a linear relationship between state and trait anxiety did exist, was examined for common characteristics. Locus of control was hypothesized to be a variable that would differentiate this group. Other suggestions for further study include use of audio-visual forms of the survival guide, extension to other subject areas, and replication of the study. / Graduation date: 1991

Longitudinal substance abuse research has often been compromised by high rates of attrition, thought to be the result of the lifestyle that often accompanies addiction. Several studies have used a standardized follow-up protocol to minimize attrition, however it is unclear whether this protocol is equally effective for participants struggling with varying levels of housing stability, support for sobriety, and substance abuse severity. The current study extends research supporting the effectiveness of this protocol by demonstrating the importance of two central aspects of the follow-up protocol: locator form completion and continual verification contacts. Results indicated that each additional piece of locator form information and verification contact significantly and independently increased the odds for completing a follow-up interview, and that these effects were not moderated by participant characteristics. Practical and theoretical implications for longitudinal substance abuse research are discussed.

The GARVEE Transportation Program started by the Idaho Transportation Department has improved parts of I-84 in Boise, Idaho. These desired improvements led to the widening of a bridge over the New York Canal (NYC) in 2009. To support the wider road, additional bridge columns were installed. The new bridge columns had a larger diameter than the existing columns and raised the number of columns from 28 to 60. Construction was completed just before the irrigation season began. During the first irrigation season it was observed that waves and oscillations were occurring within the canal immediately adjacent to the bridge structure. Throughout the irrigation season, it was observed that the intensity of the oscillations would vary. It was also observed that the wave oscillations propagated upstream and downstream from the bridge structure. Both longitudinal and transverse waves were observed. The waves appeared to originate in the section of the canal that was under the I-84 Bridge. A physical model was built in 2010 at Utah State University's (USU) Utah Water Research Laboratory (UWRL) in an attempt to simulate the oscillation phenomenon and to develop potential solutions to the problem. During the original modeling work, a thorough investigation to the causes of this phenomenon was not accomplished due to time constraints. The objective of the follow-up research presented in this thesis was to qualitatively determine the causes of the oscillations. Laboratory tests were performed using the original physical model used in the original 2010 testing.

Considerable amounts of event history data are collected through longitudinal surveys. These surveys have many particularities or features that are the results of the dynamic nature of the population under study and of the fact that data collected through longitudinal surveys involve the use of complex survey designs, with clustering and stratification. These particularities include: attrition, seam-effect, censoring, left-truncation and complications in the variance estimation due to the use of complex survey designs. This thesis focuses on the last two points. Statistical methods based on the stratified Cox proportional hazards model that account for intra-cluster dependence, when the sampling design is uninformative, are proposed. This is achieved using the theory of estimating equations in conjunction with empirical process theory. Issues concerning analytic inference from survey data and the use of weighted versus unweighted procedures are also discussed. The proposed methodology is applied to data from the U. S. Survey of Income and Program Participation (SIPP) and data from the Canadian Survey of Labour and Income Dynamics (SLID). Finally, different statistical methods for handling left-truncated sojourns are explored and compared. These include the conditional partial likelihood and other methods, based on the Exponential or the Weibull distributions.

Data from longitudinal surveys give rise to many statistical challenges. They often come from a vast, heterogeneous population and from a complex sampling design. Further, they are usually collected retrospectively at intermittent interviews spaced over a long period of time, which gives rise to missing information and loss to follow-up. As a result, duration data from this kind of surveys are subject to dependent censoring, which needs to be taken into account to prevent biased analysis. Methods for point and variance estimation are developed using Inverse Probability of Censoring (IPC) weights. These methods account for the random nature of the IPC weights and can be applied in the analysis of duration data in survey and non-survey settings. The IPC estimation techniques are based on parametric estimating function theory and involve the estimation of dropout models. Survival distributions without covariates are estimated via a weighted Kaplan-Meier method and regression modeling through the Cox Proportional Hazards model and other models is based on weighted estimating functions. The observational frameworks from Statistics Canada's Survey of Labour and Income Dynamics (SLID) and the UK Millenium Cohort Study are used as motivation, and durations of jobless spells from SLID are analyzed as an illustration of the methodology. Issues regarding missing information from longitudinal surveys are also discussed.

Background: Across North America, smoking prevalence is highest among young adults (YAs). Understanding the cessation behaviours of YAs is critical given their higher smoking rates; however, there is a paucity of prospective studies on YA cessation from a population-based sample of smokers. Objectives: This study characterizes younger and older adult smokers as well as identifies the rate of making a quit attempt (QA) and smoking cessation among a representative sample of younger and older adult smokers. Guided by the Social Cognitive Theory (SCT), this study also examines the interpersonal predictors of moving toward smoking cessation among YAs. Methods: Self-report data on 592 YA and 2777 older adult smokers were compiled from the Ontario Tobacco Survey baseline and six-month follow-up interviews. Smoking cessation behaviour was measured as an ordinal variable: made no attempt to quit, made a QA that lasted for less than 30 days, and successfully quit for 30 days or longer. Design-based analyses examined the characteristics of young and older adult smokers. Making a QA and smoking cessation during a six-month follow-up period were modeled according to the SCT constructs while accounting for the complex study design. Results: Young adult smokers were more likely to be men with lower levels of addiction but greater self-efficacy and an intention to quit than their older counterparts. While YA smokers were more likely to make a QA than their older counterparts (25% vs. 17%, respectively), they were no more likely to succeed (14% vs. 10%, respectively). Having an intention to quit smoking and having made two or more lifetime number of QAs predicted making a QA; the use of smoking cessation aids or resources and having knowledge that stop smoking medications make quitting a lot easier also contributed to making an attempt to quit. Self-efficacy, use of smoking cessation aids or resources and having someone to support one‘s QA were positive predictors of quitting whereas having high levels of addiction was a negative predictor of cessation. Conclusions: Young and older adults are distinct types of smokers with different personal and smoking characteristics. Different factors predicted making a QA and smoking cessation among YAs. Smoking cessation interventions for YAs should provide social support and skills to build and maintain self-efficacy to quit. It is critical to ensure YA smokers have effective smoking cessation aids and services that are easily accessible and appropriate for this population. Future research is needed to understand long-term smoking cessation and relapse in this vulnerable population.

Data obtained from longitudinal surveys using complex multi-stage sampling designs contain cross-sectional dependencies among units caused by inherent hierarchies in the data, and within subject correlation arising due to repeated measurements. The statistical methods used for analyzing such data should account for stratification, clustering and unequal probability of selection as well as within-subject correlations due to repeated measurements. <p>The complex multi-stage design approach has been used in the longitudinal National Population Health Survey (NPHS). This on-going survey collects information on health determinants and outcomes in a sample of the general Canadian population. <p>This dissertation compares the model-based and design-based approaches used to determine the risk factors of asthma prevalence in the Canadian female population of the NPHS (marginal model). Weighted, unweighted and robust statistical methods were used to examine the risk factors of the incidence of asthma (event history analysis) and of recurrent asthma episodes (recurrent survival analysis). Missing data analysis was used to study the bias associated with incomplete data. To determine the risk factors of asthma prevalence, the Generalized Estimating Equations (GEE) approach was used for marginal modeling (model-based approach) followed by Taylor Linearization and bootstrap estimation of standard errors (design-based approach). The incidence of asthma (event history analysis) was estimated using weighted, unweighted and robust methods. Recurrent event history analysis was conducted using Anderson and Gill, Wei, Lin and Weissfeld (WLW) and Prentice, Williams and Peterson (PWP) approaches. To assess the presence of bias associated with missing data, the weighted GEE and pattern-mixture models were used.<p>The prevalence of asthma in the Canadian female population was 6.9% (6.1-7.7) at the end of Cycle 5. When comparing model-based and design- based approaches for asthma prevalence, design-based method provided unbiased estimates of standard errors. The overall incidence of asthma in this population, excluding those with asthma at baseline, was 10.5/1000/year (9.2-12.1). For the event history analysis, the robust method provided the most stable estimates and standard errors. <p>For recurrent event history, the WLW method provided stable standard error estimates. Finally, for the missing data approach, the pattern-mixture model produced the most stable standard errors <p>To conclude, design-based approaches should be preferred over model-based approaches for analyzing complex survey data, as the former provides the most unbiased parameter estimates and standard errors.

none

In optical disk systems, a semiconductor laser is used to read out the data recorded on the disc. Since the laser is the first noise source, there are strictly rated values for laser's noise in various optical disk systems to ensure the normal operation of the system. Among different laser noises, the worst one is the optical feedback noise. The feedback light will disturb the longitudinal modes of the laser and induce huge fluctuation in Laser's output. In our work, we study the effect of optical feedback on Laser's modes and relative intensity noises under various driving current and chop temperature. We try to find out methods that can suppress the Laser's noise and try to give some suggestions for the design of disc driven. Some experiments about a commercialized optical disk driver are also reported as well.

In this day and age, information technology to daily life is now universal. The Internet is a global system that provides innovative services. This study focused on treating the feelings and intentions of new users that has not been used at the hedonic website. As well as expectations and intentions during and after a month of usage. Through this study, the self-developed innovative website has created called iMemory. During the first survey, the subjects were on display for users. After measuring the hearts of users show the expected feelings and intentions.A month later, the same measure by measuring the extent of use, the use of feelings and intentions. In this study, based on technology acceptance model, by adding perceived enjoyment that the period of one month longitudinal study. To compare the differences between two results. The results showed that the second measurement of the use of feelings and intentions are will be the first to use measurements of the feelings and intentions significant impact on the use of the past month and the remarkable degree of influence. The second measure of perceived ease of use and perceived usefulness of intent with the impact is not significant, but perceived enjoyment of intent are still significantly affected. Finally, this study based on data analysis for discussion.