In this paper, we revisit, theoretically and experimentally, the fall of a folded U-chain and of a pile-chain. The model calculation implies the division of the whole system into two subsystems of variable mass, allowing us to explore the role of tensional contact forces at the boundary of the subsystems. This justifies, for instance, that the…

Objective: The goal of the study was to assess the validity and feasibility of a digital diet estimation method for use with preschool children in "Head Start." Methods: Preschool children and their caregivers participated in validation (n = 22) and feasibility (n = 24) pilot studies. Validity was determined in the metabolic research unit using…

This study empirically examines a prominent justification for public subsidies of emerging technologies: that stimulating demand for them provides opportunities for learning by doing. Even if firms learn from their experience, subsidies are still second best to pricing negative externalities if firms can appropriate the benefits of learning. I…

Subitizing is traditionally described as the rapid, preattentive and automatic enumeration of up to four items. Counting, by contrast, describes the enumeration of larger sets of items and requires slower serial shifts of attention. Although recent research has called into question the preattentive nature of subitizing, whether or not numerosities…

The likelihood for generalized linear models with covariate measurement error cannot in general be expressed in closed form, which makes maximum likelihood estimation taxing. A popular alternative is regression calibration which is computationally efficient at the cost of inconsistent estimation. We propose an improved regression calibration…

A simple activity using cheap and readily available materials is described that allows students to experience first hand many of the concepts of measurement, uncertainty and graph drawing without laborious measuring or calculation. (Contains 9 figures.)

This note describes how to theoretically calculate and experimentally measure the moment of inertia of a Ping-Pong[R] ball. The theoretical calculation results are in good agreement with the experimental measurements that can be reproduced in an introductory physics laboratory.

This study demonstrates how the stability of Mantel-Haenszel (MH) DIF (differential item functioning) methods can be improved by integrating information across multiple test administrations using Bayesian updating (BU). The authors conducted a simulation that showed that this approach, which is based on earlier work by Zwick, Thayer, and Lewis,…

The purpose of this research was to determine if recognizable error types exist in the work of preservice teachers required to create story problems for specific fraction operations. Students were given a particular single-operation fraction expression and asked to do the calculation and then create a story problem that would require the use of…

Although clinical practitioners often express concerns about the mathematical functioning of children with autism spectrum disorder (ASD), the field of mathematics remains a relatively unexplored topic in individuals with ASD. Moreover, research findings are fragmentary and hold inconclusive results. The present study aimed to examine whether…

Number sense is one's ability to understand what numbers mean, perform mental mathematics, and look at the world and make comparisons. Researchers show instruction that teaches children how to classify numbers, put numbers in sequence, conserve numbers effectively, and count builds their number sense skills. Targeted instruction that teaches…

This paper analyses the returns to education of specific occupations in Canada. The purpose is to scrutinize whether and in how far academic and vocational education do differ in monetary benefits regarding individual returns. Therefore, two different methodologies of calculation are used to compute the concrete returns to education. As a result…

The use of collaborative problem solving within mathematics education is imperative in this day and age of integrative science. The formation of interdisciplinary teams of mathematicians and scientists to investigate crucial problems is on the rise, as greater insight can be gained from an interdisciplinary perspective. Mathematical modelling, in…

Teacher value-added models (VAMs) must isolate teachers' contributions to student achievement to be valid. Well-known VAMs use different specifications, however, leaving policymakers with little clear guidance for constructing a valid model. We examine the sensitivity of teacher value-added estimates under different models based on whether they…

The purpose of this mixed method study was to investigate future special education teachers' preparation for effectively teaching mathematics. During the last semester of their program, pre-service special education teachers completed elementary level mathematics computation and problem solving assessments, a mathematics efficacy beliefs survey,…