The low number of college graduates with science degrees--particularly among underrepresented minorities--is of growing concern. We examine differences across universities in graduating students in different fields. Using student-level data on the University of California system during a period in which racial preferences were in place, we show…

A multilevel latent transition analysis (LTA) with a mixture IRT measurement model (MixIRTM) is described for investigating the effectiveness of an intervention. The addition of a MixIRTM to the multilevel LTA permits consideration of both potential heterogeneity in students' response to instructional intervention as well as a methodology for…

Gaps in achievement test scores continue to exist in students depending upon race, gender, income, and ethnicity according to the Center on Education Policy (CEP), an advocate for public schools. School districts and schools are struggling to close the achievement gap that exists. In the 2010-2011 school years, 34.4% of African American students…

This brief shows how middle and high school teachers in a Time-Technology Swap school model, with or without Multi-Classroom Leaders, may earn more while reaching more students, sustainably. In this model, students alternate between learning with teachers and working in a digital learning lab, where they learn online and engage in offline skill…

In education randomized control trials (RCTs), the misreporting of student outcome data could lead to biased estimates of average treatment effects (ATEs) and their standard errors. This article discusses a statistical model that adjusts for misreported binary outcomes for two-level, school-based RCTs, where it is assumed that misreporting could…

A great number of teachers in the United States have found themselves wrestling with an internal conflict between their teaching beliefs and a need to revert back to traditional modes of teaching in order to have their students demonstrate proficiency on high-stakes tests. While they want to include more non-traditional methods in their repertoire…

This third edition of the best-selling "Mathematics in Nursery Education" provides an accessible introduction to the teaching of mathematics in the early years. Covering all areas of mathematics learning--number and counting, calculation, pattern, shape, measures and data handling--it summarises the research findings and underlying key concepts…

This paper investigates the contribution of mathematical knowledge for teaching (MKT) and curriculum materials to the mathematical quality of instruction by comparing the enactment of a fractions problem taught by two teachers with differing MKT. It was found that MKT seem to support teachers' precise use of mathematical language and to prevent…

Multisite trials can clarify the average impact of a new program and the heterogeneity of impacts across sites. Unfortunately, in many applications, compliance with treatment assignment is imperfect. For these applications, we propose an instrumental variable (IV) model with person-specific and site-specific random coefficients. Site-specific IV…

We develop a variational theory of hot nuclear matter in neutron stars and supernovae. It can also be used to study charged, hot nuclear matter which may be produced in heavy-ion collisions. This theory is a generalization of the variational theory of cold nuclear and neutron star matter based on realistic models of nuclear forces and pair…

The Cox proportional hazards model and the accelerated failure time model are frequently used in survival data analysis. They are powerful, yet have limitation due to their model assumptions. Quantile regression offers a semiparametric approach to model data with possible heterogeneity. It is particularly powerful for censored responses, where the…

Data compression is the art of using encoding techniques to represent data symbols using less storage space compared to the original data representation. The encoding process builds a relationship between the entropy of the data and the certainty of the system. The theoretical limits of this relationship are defined by the theory of entropy in…

A clear view of the ocean may be used to measure the radius of the Earth. To an observer looking out at the ocean, the horizon will always form some angle [theta] with the local horizontal plane. As the observer's elevation "h" increases, so does the angle [theta]. From measurements of the elevation "h" and the angle [theta],…

This cross-sectional study using direct motion monitoring evaluated whether short epochs increased estimates of moderate or vigorous physical activity (MPA or VPA) and enhanced differences in daily VPA comparing overweight (OW) and nonoverweight (NOW) children. Seventy-seven children (ages 8-10 years) wore accelerometers for 7 days. We calculated…

The study of intraindividual variability is central to the study of individuals in psychology. Previous research has related the variance observed in repeated measurements (time series) of individuals to traitlike measures that are logically related. Intraindividual measures, such as intraindividual standard deviation or the coefficient of…