Kappa (Cohen, 1960) is a popular agreement statistic used to estimate the accuracy of observers. The response of kappa to differing baserates was examined and methods for estimating the accuracy of observers presented. Results suggest that setting a single value of kappa as "minimally acceptable" (i.e., a criterion value) is not useful in ensuring…

The concept of risk has entered into physics courses in various guises. It is treated explicitly in the "Advancing Physics" [1] course and implicitly at GCSE through "Ideas and Evidence" discussions. This could easily lead to such ideas as the balance between treatment and risk in radiotherapy and the likelihood of an asteroid strike. In this…

The absorbance decay of hexacyanoferrate(III) as a function of time shows a progressive deviation from zero to first order. This variation follows an experimental rate law that has been analyzed. The change in reaction order is due to a change in the relative rate of substrate oxidation with respect to that of catalyst regeneration. (Contains 2…

This article describes the combinatorial thinking involved in computing one's score in the game of cribbage. It deals only with counting the hand; it does not describe the game in its entirety.

This article employs the Archimedean method of estimating the value of pi within an inscribed pentagon. We show how to write these approximations in terms of the golden ration.

Methods for planning sample size (SS) for the standardized mean difference so that a narrow confidence interval (CI) can be obtained via the accuracy in parameter estimation (AIPE) approach are developed. One method plans SS so that the expected width of the CI is sufficiently narrow. A modification adjusts the SS so that the obtained CI is no…

Accurate and accessible expressions for the probability of having a matching birthday are obtained by using Stirling's formula and Taylor series. For interest, the results are applied to the planets of our solar system.

This article discusses the challenges students face in making sense of zero as a number. A range of different student responses to a computation problem involving zero reveal students' different understandings of zero.

A Lattice Energy Spreadsheet by Christopher King, which can help instructors and students to easily calculate crystal lattice energies in many binary compounds, is introduced.

This article examines a wide range of parish school indicators that can be used to predict long-term viability. The study reported in this article explored the relationship between demographic variables, financial variables, and parish grade school closures in the Archdiocese of Saint Louis. Specifically, this study investigated whether…

This article considers models involving a single structural equation with latent explanatory and/or latent dependent variables where discrete items are used to measure the latent variables. Our primary focus is the use of scores as proxies for the latent variables and carrying out ordinary least squares (OLS) regression on such scores to estimate…

We introduce a computer exercise that bridges spectroscopy and thermodynamics using statistical mechanics and the experimental data taken from the commonly used laboratory exercise involving the rotational-vibrational spectrum of HCl. Based on the results from the analysis of their HCl spectrum, students calculate bulk thermodynamic properties…

Diezmann presents a series of classroom number-sense activities that encourage young students to use and refine their estimation, prediction, and observation skills. The activities explore the relationships between the number of objects in an opaque container and (1) its fullness and (2) the size of the objects in the container. Informal,…

This article investigates the utility of various estimates of mathematics proficiency. The participants were 432 students in Grades 2 through 5. The delayed alternate form reliability of multiskill probes, retention probes, slopes of student growth, and trials to criterion were computed. The fluency probes were found to be both sufficiently…

This paper focuses on the changes in thinking involved in the transition from school mathematics to formal proof in pure mathematics at university. School mathematics is seen as a combination of visual representations, including geometry and graphs, together with symbolic calculations and manipulations. Pure mathematics in university shifts…