From Sharing to Balancing – No Mean Feat!

This article suggests how to move from the primary school notion of the average being ‘fair shares for all’ to the secondary school idea of the mean being a ‘balancing point’.     

The Royal Statistical Society Centre For Statistical Education

We present our vision for the Centre’s role in raising statistical standards in the new millennium, particularly in relation to schools.     

Making the failure more productive: scaffolding the invention process to improve inquiry behaviors and outcomes in invention activities

Invention activities are Productive Failure activities in which students attempt (and often fail) to invent methods that capture deep properties of a construct before being taught expert solutions. The current study evaluates the effect of scaffolding on the invention processes and outcomes, given that students are not expected to succeed in their inquiry and that all students receive subsequent instruction. While socio-cognitive theories of learning advocate for scaffolding in inquiry activities, reducing students’ agency, and possibly their failure rate, may be counter-productive in this context. Two Invention activities related to data analysis concepts were given to 87 undergraduate students in a first-year physics lab course using an interactive learning environment. Guided Invention students outperformed Unguided Invention students on measures of conceptual understanding of the structures of the constructs in an assessment two months after the learning period. There was no effect, however, on measures of procedural knowledge or conceptual understanding of the overall goals of the constructs. In addition, Guided Invention students were more likely to invent multiple methods during the Invention process. These results suggest that the domain-general scaffolding in Invention activities, when followed by instruction, can help students encode deep features of the domain and build on their failures during Productive Failure. These results further suggest not all failures are equally productive, and that some forms of support help students learn form their failed attempts.     

Use of the probit model to estimate school performance in student attainment of achievement testing standards

In the USA, trends in educational accountability have driven several models attempting to provide quality data for decision making at the national, state, and local levels, regarding the success of schools in meeting standards for competence. Statistical methods to generate data for such decisions have generally included (a) status models that examine simple indications of number of students meeting a criterion level of achievement, (b) growth models that explore change over the course of one or more years, and (c) value-added models that attempt to control for factors deemed relevant to student achievement patterns. This study examined a new strategy for student and school achievement modeling that augments the field through the use of the probit model to estimate the likelihood of students meeting an established level standard and estimating the proportion of individuals within a school meeting the standard. Results of the study showed that the probit model was an effective tool both for providing such adjustments, as well as for adjusting them based upon salient demographic variables. Implications of these results and suggestions for further use of the model are discussed.     

Deformability-based red blood cell separation in deterministic lateral displacement devices—A simulation study

We show, via three-dimensional immersed-boundary-finite-element-lattice-Boltzmann simulations, that deformability-based red blood cell (RBC) separation in deterministic lateral displacement (DLD) devices is possible. This is due to the deformability-dependent lateral extension of RBCs and enables us to predict a priori which RBCs will be displaced in a given DLD geometry. Several diseases affect the deformability of human cells. Malaria-infected RBCs, for example, tend to become stiffer than their healthy counterparts. It is therefore desirable to design microfluidic devices which can detect diseases based on the cells'' deformability fingerprint, rather than preparing samples using expensive and time-consuming biochemical preparation steps. Our findings should be helpful in the development of new methods for sorting cells and particles by deformability.     

A Substrata Analysis of Spelling Ability for Elements of Auditory Images

ABSTRACT. Two groups of middle school students were taught U.S. colonial history during a 5-week period using 2 different instructional strategies. In the experimental group, concepts and problem-solving strategies were explicitly taught; in the control group, content was presented using lectures and reading. All students took a pretest and several posttests. Declarative knowledge tasks measured factual content knowledge and domain vocabulary acquisition; procedural knowledge was measured with problem-solving essays. Whereas performance was not statistically different between the 2 groups on the fact tests, significant differences were found on the vocabulary tests and problem-solving essays. These findings support using direct instruction for relational thinking and problem solving with explicit reference to concepts and attributes.     

Physical Discipline Use and Child Behavior Problems in Low-Income,High-Risk African American Families

This article has been retracted.     

Valid and Reliable Science Content Assessments for Science Teachers

Science teachers’ content knowledge is an important influence on student learning, highlighting an ongoing need for programs, and assessments of those programs, designed to support teacher learning of science. Valid and reliable assessments of teacher science knowledge are needed for direct measurement of this crucial variable. This paper describes multiple sources of validity and reliability (Cronbach’s alpha greater than 0.8) evidence for physical, life, and earth/space science assessments—part of the Diagnostic Teacher Assessments of Mathematics and Science (DTAMS) project. Validity was strengthened by systematic synthesis of relevant documents, extensive use of external reviewers, and field tests with 900 teachers during assessment development process. Subsequent results from 4,400 teachers, analyzed with Rasch IRT modeling techniques, offer construct and concurrent validity evidence.