Teri Reed Rhoads

The statistics concept inventory: a pilot study

The statistics concept inventory (SCI) is a multiple choice testing instrument that is being developed to assess student understanding of fundamental statistics concepts and to identify commonly held misconceptions. This study pilot tested the SCI with four different introductory statistics courses with students from a broad range of disciplines. The effects of discipline and gender on performance on the SCI were investigated along with the relationship of mathematics experience, statistics experience, and attitude toward statistics as measured with the survey of attitudes toward statistics (SATS) [Schau, C. et al., 2002]. The results of this study indicate that discipline has a small effect on performance on the SCI. Mathematics majors performed significantly better than social science majors, but no other pair of majors performed significantly different. The effect of gender on performance was significant with males outperforming females. SCI scores were positively correlated with mathematics experience and with attitude scores obtained on the SATS. SCI scores were not found to be correlated with statistics experience.

Assessment of repairable-system reliability using proportional intensity models: a review

This paper provides an overview of methods, and surveys the literature on engineering applications of proportional intensity (PI) models with explanatory variables (covariates), for repairable systems reliability assessment. The semi-parametric PI method relaxes the assumption of an underlying distribution, and is potentially useful in engineering practice, where the underlying information for a failure process is usually not available. PI semi-parametric models initially proposed for clinical studies in medical applications include PWP (Prentice, Williams, and Peterson), AG (Andersen, and Gill), and WLW (Wei, Lin, and Weissfeld). Abundant funding received in medical research has advanced PI models to become well developed, and widely referenced in the biostatistics field. This paper reviews both the available methods for repairable-system reliability assessment, and the published engineering application case studies. An engineering application example that applies PI model to a maintainability process used in US Army M1A2 Arams Main Battle Tank is presented.

Semi-parametric proportional intensity models robustness for right-censored recurrent failure data

This paper reports the robustness of the four proportional intensity (PI) models: Prentice–Williams–Peterson-gap time (PWP-GT), PWP-total time (PWP-TT), Andersen–Gill (AG), and Wei–Lin–Weissfeld (WLW), for right-censored recurrent failure event data. The results are beneficial to practitioners in anticipating the more favorable engineering application domains and selecting appropriate PI models. The PWP-GT and AG prove to be models of choice over ranges of sample sizes, shape parameters, and censoring severity. At the smaller sample size (U=60), where there are 30 per class for a two-level covariate, the PWP-GT proves to perform well for moderate right-censoring (Pc≤0.8), where 80% of the units have some censoring, and moderately decreasing, constant, and moderately increasing rates of occurrence of failures (power-law NHPP shape parameter in the range of 0.8≤δ≤1.8). For the large sample size (U=180), the PWP-GT performs well for severe right-censoring (0.8<Pc≤1.0), where 100% of the units have some censoring, and moderately decreasing, constant, and moderately increasing rates of occurrence of failures (power-law NHPP shape parameter in the range of 0.8≤δ≤2.0). The AG model proves to outperform the PWP-TT and WLW for stationary processes (HPP) across a wide range of right-censorship (0.0≤Pc≤1.0) and for sample sizes of 60 or more.

Gender Equity in Industrial Engineering: A Pilot Study

We report on findings from a pilot study focused on the Industrial Engineering Department at University of Oklahoma where gender equity has been achieved. The study identifies factors that may contribute to gender parity in engineering and science fields.

Proportional Intensity Models Robustness with Overhaul Intervals

The class of semi-parametric proportional intensity (PI) models applies to recurrent failure event modeling for a repairable system with explanatory variables (covariates). Certain repairable systems (e.g. aircraft and electrical power generating plants) experience a substantial period of downtime due to performing maintenance (i.e. major overhaul) at scheduled intervals or following a major failure. Other systems (e.g. emergency power units) experience extended periods of non-operating dormancy. These discontinuities in observation time have potential effects on the accuracy of estimation for covariate effects, particularly where calendar time is the life metric. This paper examines the robustness of two PI methods (Prentice–Williams–Peterson gap time (PWP-GT) and Andersen–Gill (AG)) as a function of the overhaul or dormancy duration. The PWP-GT model proves to perform well for sample size of 60 (30 per level of a class covariate), constant or moderately decreasing/increasing rate of occurrence of failures, and relative overhaul (dormancy) durations less than half of the immediately preceding interval between failures. The AG model performs consistently well for a small sample size of 20 (10 per level of a class covariate) for homogeneous Poisson processes, regardless of the relative overhaul (dormancy) duration. Copyright

A laptop College of Engineering at the University of Oklahoma

Since 1998 every entering freshman entering the College of Engineering at the University of Oklahoma (OU) has been required to have use of a laptop computer. The first engineering course, Introduction to Engineering, was redesigned to use laptops. Attempts to extend the laptop to other years and other courses revealed the need for a total infrastructure approach to the use of laptops. This paper describes the steps that the OU College of Engineering has taken to effectively integrate laptop computing into the curriculum. The College developed a vision and strategy for its laptop program, which affects most aspects of its undergraduate education. Specific actions have included the refurbishing of classrooms to be laptop compatible, the evaluation of tradeoffs between wired and wireless communication for the laptops (and between wireless protocols), the training of instructors in use of the laptops for education, and the training of students to use them. Assessment of the laptop program has been made by surveying students and faculty and by assessing the costs and benefits of the program. Barriers to more extensive use of laptops have been assessed and actions planned to address them.

Colleges of engineering and education: partniering for effective community outreach

With the growing influence and increasing complexity of technology, the public must have a certain level of technological understanding to make informed decisions and to attain a reasonable quality of life. It is crucial that current and future teachers have the resources, skills, knowledge and support to empower students to make informed decisions as citizens, consumers, and as members of the workforce. Colleges of Engineering and Education can take a leadership role in providing effective outreach programs for the pre-college community. This panel session will feature: 1) a summary of Deans Summit II: Fostering Campus Collaborations attended by deans and faculty from colleges of education and engineering, 2) representatives from colleges of education and engineering describing successful campus collaborations between Colleges of Engineering and Education that have resulted in effective outreach programs to the pre-college community, 3) pre-college educators who have participated in these collaborative programs, and 4) a representative from industry discussing the potential role of the business community in these collaborations. Index Terms – Collaborations, Colleges of Engineering and Education, Community Outreach, Technological Literacy,