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The focus of precision medicine is on decision support, often in the form of dynamic treatment regimes (DTRs), which are sequences of decision rules. At each decision point, the decision rules determine the next treatment according to the patient's baseline characteristics, the information on treatments and responses accrued by that point, and the patient's current health status, including symptom severity and other measures. However, DTR estimation with ordinal outcomes is rarely studied, and rarer still in the context of interference - where one patient's treatment may affect another's outcome. In this paper, we introduce the weighted proportional odds model (WPOM): a regression-based, approximate doubly-robust approach to single-stage DTR estimation for ordinal outcomes. This method also accounts for the possibility of interference between individuals sharing a household through the use of covariate balancing weights derived from joint propensity scores. Examining different types of balancing weights, we verify the approximate double robustness of WPOM with our adjusted weights via simulation studies. We further extend WPOM to multi-stage DTR estimation with household interference, namely dWPOM (dynamic WPOM). Lastly, we demonstrate our proposed methodology in the analysis of longitudinal survey data from the Population Assessment of Tobacco and Health study, which motivates this work. Furthermore, considering interference, we provide optimal treatment strategies for households to achieve smoking cessation of the pair in the household.

In precision medicine, Dynamic Treatment Regimes (DTRs) are treatment protocols that adapt over time in response to a patient's observed characteristics. A DTR is a set of decision functions that takes an individual patient's information as arguments and outputs an action to be taken. Building on observed data, the aim is to identify the DTR that optimizes expected patient outcomes. Multiple methods have been proposed for optimal DTR estimation with continuous outcomes. However, optimal DTR estimation with binary outcomes is more complicated and has received comparatively little attention. Solving a system of weighted generalized estimating equations, we propose a new balancing weight criterion to overcome the misspecification of generalized linear models' nuisance components. We construct binary pseudo-outcomes, and develop a doubly-robust and easy-to-use method to estimate an optimal DTR with binary outcomes. We also outline the underlying theory, which relies on the balancing property of the weights; provide simulation studies that verify the double-robustness of our method; and illustrate the method in studying the effects of e-cigarette usage on smoking cessation, using observational data from the Population Assessment of Tobacco and Health (PATH) study.

The R software has become popular among researchers due to its flexibility and open-source nature. However, researchers in the fields of public health and epidemiological studies are more customary to commercial statistical softwares such as SAS, SPSS and Stata. This paper provides a comprehensive comparison on analysis of health survey data using the R survey package, SAS, SPSS and Stata. We describe detailed R codes and procedures for other software packages on commonly encountered statistical analyses, such as estimation of population means and regression analysis, using datasets from the Canadian Longitudinal Study on Aging (CLSA). It is hoped that the paper stimulates interest among health science researchers to carry data analysis using R and also serves as a cookbook for statistical analysis using different software packages., Comment: There is a data usage issue with the paper and it is requested by the data owner (CLSA) to withdraw the paper at this time

In this paper, we propose new nonparametric approach to network inference that may be viewed as a fusion of block sampling procedures for temporally and spatially dependent processes with the classical network methodology. We develop estimation and uncertainty quantification procedures for network mean degree using a "patchwork" sample and nonparametric bootstrap, under the assumption of unknown degree distribution. We investigate asymptotic properties of the proposed patchwork bootstrap procedure and present cross-validation methodology for selecting an optimal patch size. We validate the new patchwork bootstrap on simulated networks with short and long tailed mean degree distributions, and revisit the Erdos collaboration data to illustrate the proposed methodology., Comment: The paper has been withdrawn by the authors: a general revision of methodology is needed

Discussion of Conditional growth charts [math.ST/0702634], Comment: Published at http://dx.doi.org/10.1214/009053606000000650 in the Annals of Statistics (http://www.imstat.org/aos/) by the Institute of Mathematical Statistics (http://www.imstat.org)

This longitudinal study focused on predicting student outcomes through multiple test scores and vocational preferences using standardized instruments and self-reports of career plans. A total of 444 students in the class of 1986 were enrolled in either a non-vocational or vocational curriculum at one of 4 high schools in a small, rural, working-class school district during the 4 academic years between 1982-83 and 1985-86 and completed from 1 to 4 standardized tests as part of the district's comprehensive testing program. Three hundred and fourteen of these students actually graduated in 1986; these graduates were all administered the Differential Aptitude Test, Ohio Vocational Interest Survey, California Achievement Test, and Stanford Achievement Test; and they were mailed a follow-up questionnaire. Using the stepwise method of discriminant analysis to predict group membership, classification efficiency ranged from 61% to 74%, indicating that a significant portion of the class might have benefited from an alternative curriculum. Career choice and actual plans were more likely influenced by socioeconomic status, rural location, and expressed vocational preference than by actual test scores. Results suggest that some of the non-vocational students might have been more successful in a vocational curriculum. School counselors must help students achieve more congruence between test scores, expressed vocational choice, and their mitigating environmental circumstances. Four data tables and a 23-item list of references are included. (Author/TJH)

A discussion of the debate over multicultural education in colleges and universities looks at the evolution of the movement and examines some myths about it that threaten its effectiveness. An effective approach to multiculturalism is seen to have implications for institutional philosophy, structure, operations, and academic programs. Concrete administrative actions are suggested. (MSE)

Reports on a study of effects of teaching styles, student cognitive styles, matched and mismatched conditions, and student age and gender in relation to the course grades of 207 community college students. Indicates that concrete sequential teachers assigned the lowest grades and that students over 24 attained higher grades than younger students except when matched with concrete random teachers. (25 references) (MAB)

Considerable study has been focused on relationships between learning styles and other characteristics and conditions, such as teaching styles, achievement, student age, and student gender. In 1991, a study was conducted on two campuses of a comprehensive community college in the southeast to measure the effect on course grades of the relationship between matched and mismatched teaching and learning styles, and between learning styles and student age and gender. The Gregorc Style Delineator (GSD) was employed to determine the dominant styles of both teachers (N=16) and students (N=207). GSD uses a quaternary design to place study subjects in one of the following learning styles: Concrete Sequential (CS), Abstract Sequential (AS), Abstract Random (AR), and Concrete Random (CR). Data from the study were analyzed using two analysis of variance (ANOVA) models. In the first ANOVA model, significant main effects were manifested in regard to teaching style and age group. In addition, significant interaction effects were observed between teaching style and student age group (i.e., CS, AS, and AR teachers assigned higher grades to students 25 years of age and older, while the pattern for grades assigned by CR teachers was reversed). Similar effects were observed between teaching style and student gender. In the second ANOVA model, no significant main effects were present for either student learning style or matched and mismatched conditions. However, analysis of data suggested that students whose learning styles were mismatched with the styles of their teachers tended to receive higher grades. A 24-item bibliography is included. (JMC)

We have developed and deployed a distributed-parallel storage system (DPSS) in several high speed asynchronous transfer mode (ATM) wide area networks (WAN) testbeds to support several different types of data-intensive applications. Architecturally, the DPSS is a network striped disk array, but is fairly unique in that its implementation allows applications complete freedom to determine optimal data layout, replication and/or coding redundancy strategy, security policy, and dynamic reconfiguration. In conjunction with the DPSS, we have developed a 'top-to-bottom, end-to-end' performance monitoring and analysis methodology that has allowed us to characterize all aspects of the DPSS operating in high speed ATM networks. In particular, we have run a variety of performance monitoring experiments involving the DPSS in the MAGIC testbed, which is a large scale, high speed, ATM network and we describe our experience using the monitoring methodology to identify and correct problems that limit the performance of high speed distributed applications. Finally, the DPSS is part of an overall architecture for using high speed, WAN's for enabling the routine, location independent use of large data-objects. Since this is part of the motivation for a distributed storage system, we describe this architecture.

Current developments in the preparation of college teachers were examined based on interviews, first-hand observations, and review of program details and individual student reactions to them. An overview of the circumstances that focus attention on college teaching and issues specific to the Doctor of Arts degree are presented. Alternatives to the Doctor of Arts program, including multiple track PhDs and the EdD and other less than doctoral level offerings, are considered as a basis for suggesting improvements. Basic considerations involved in developing a degree for college teaching and the overall characteristics of a teaching degree, with particular attention to the substantive requirements, are discussed. Additional topics include: the needs and requirements in the professional area, practices and problems defining and carrying out effective internships, the problems of examinations and evaluation and their role in a teacher preparation program; and views of Doctor of Arts candidates and degree recipients. A bibliography is included. (SW)

A change process described in the work of Yochelson and Samenow was adapted to students committed as delinquents to a state correctional facility. Their criminal profile accurately described the majority of the offenders. While minor problems continued, their frequency was reduced by as much as nine times. Serious incidents occurred only after the student terminated his contract. Meeting with the change agents almost daily and being held accountable for all choices seemed to act as an effective, immediate deterrent. (BN)

Since the early 1980s, blue ribbon commissions and task forces have focused their attention upon identifying problems and suggesting solutions to shortcomings within the public educational system. Some of the questions that can be raised include the following: (1) Who are these citizens interested in educational practices? (2) What solutions have they proposed? and (3) How is public education linked with the health of the American economy? This paper addresses these questions as well as providing a view of the educational reform movement from the perspective of a vocational educator. Successful practices within the field of vocational education are identified with special emphasis upon the cooperative education method. The paper is organized in four sections. The first section provides a definitional focus for examining the educational reform movement. Section 2 contains a summary of 11 commission findings and recommendations. The effects of reform recommendations upon practices in public schools are reviewed in the third section. In the final section, strategies for implementing recommendations, including an expansion and updating of cooperative vocational programs, are proposed. (KC)