None of the techniques -- sorting, scatter graphs, grouping, or calculating means -- that are highlighted in this work are particularly sophisticated, and yet their simplicity is often more than adequate for displaying the trends in data or for making comparisons in a convincing way. These are strategies that are easy to introduce to students and…

A two-year project was conducted, mainly with two goals, to make the students fluent in addition and subtraction and to have the students develop an understanding of computation that was strong enough to solve more than routine problems. The most common method for teaching children computation is teaching the standard procedures and then giving…

The calculations of uncertainties in the formula or molar masses of compounds are streamlined. Three rules of increasing complexity are proposed, which overestimate the uncertainty so there is little if any risk that the true values are missed.

In European countries, field studies investigate how citizens acquire knowledge of the new currency, the euro. In 3 laboratory experiments, the authors recruited 168 undergraduates to examine whether such accurate knowledge is acquired from learning prices in the new currency. The results show fast learning of prices of duration of cellular phone…

A family of integrals over infinite intervals appears frequently in the statistical literature on non-parametric regression. This note presents two simple transform methods, based on beta function and Parseval identity, to explicitly evaluate these integrals. These methods will benefit researchers and practitioners working in non-parametric…

A common type of problem encountered in mathematics is optimizing nonlinear functions. Many popular algorithms that are currently available for finding nonlinear least squares estimators, a special class of nonlinear problems, are sometimes inadequate. They might not converge to an optimal value, or if they do, it could be to a local rather than…

Is it possible to learn the relation between 2 nonadjacent events? M. Pena, L. L. Bonatti, M. Nespor, and J. Mehler (2002) claimed this to be possible, but only in conditions suggesting the involvement of algebraic-like computations. The present article reports simulation studies and experimental data showing that the observations on which Pe?a et…

This article introduces a procedure for estimating reliability in which equivalent halves of a given test are systematically created and then administered a few days apart so that transient error can be included in the error calculus. The procedure not only estimates complete reliability (taking into account both specific-factor error and…

The author describes a card trick that failed when he tried it with the student chapter at his university. Computations show that the chance of this happening is about 1 in 25.

This article discusses prime numbers, defined as integers greater than 1 that are divisible only by only themselves and the number 1. A positive integer greater than 1 that is not a prime is called composite. The number 1 itself is considered neither prime nor composite. As the name suggests, prime numbers are one of the most basic but important…

This study provides an in-depth analysis of children's use of a taught mental calculation strategy. Three children (aged eight to nine years) who demonstrated contrasting spontaneous calculation approaches, were interviewed following the direct instruction of a calculation strategy. Their responses are explored in relation to constructivist and…

Some simple, nonoptimized coefficients (e.g., correlation weights, equal weights) were pitted against regression in extensive prediction competitions. After drawing calibration samples from large supersets of real and synthetic data, the researchers observed which set of sample-derived coefficients made the best predictions when applied back to…

This article presents two methods of estimating a study's replicability that researchers should consider reporting along with their statistical significant and effect size findings. One method of estimating the replicability of the findings deals with replication in the exact same system. The second method, which may contain subjective probability…

The emerging field of Evolutionary Computation (EC), inspired by neo-Darwinian principles (e.g. natural selection, mutation, etc.), offers developmental psychologists a wide array of mathematical tools for simulating ontogenetic processes. In this brief review, I begin by highlighting three of the approaches that EC researchers employ (Artificial…

We investigate the pendulum equation [theta] + [lambda][squared] sin [theta] = 0 and two approximations for it. On the one hand, we suggest that the third and fifth-order Taylor series approximations for sin [theta] do not yield very good differential equations to approximate the solution of the pendulum equation unless the initial conditions are…