In discussions with leading educators from many different fields, MAA's CRAFTY (Curriculum Renewal Across the First Two Years) committee found that one of the most common mathematical themes in those other disciplines is the idea of fitting a function to a set of data in the least squares sense. The representatives of those partner disciplines…

This article reports on the action taken by Texas officials to maintain the integrity of their testing program. Responding to a potential cheating scandal uncovered by a recent newspaper investigation, Texas officials announced a sweeping review of test security and plans for a new monitoring scheme for the state accountability system, which has…

Multiple regression and correlation (MRC) methods form a flexible family of statistical techniques that can address a wide variety of different types of research questions of interest to rehabilitation professionals. In this article, we review basic concepts and terms, with an emphasis on interpretation of findings relevant to research questions…

Most reading time studies using naturalistic texts yield data sets characterized by a multilevel structure: Sentences (sentence level) are nested within persons (person level). In contrast to analysis of variance and multiple regression techniques, hierarchical linear models take the multilevel structure of reading time data into account. They…

An enzymatic laboratory experiment based on the analysis of serum is described that is suitable for students of clinical chemistry. The experiment incorporates an introduction to mathematical method-comparison techniques in which three different clinical glucose analysis methods are compared using linear regression and Bland-Altman difference…

SigrafW is Windows-compatible software developed using the Microsoft[R] Visual Basic Studio program that uses the simplified Hill equation for fitting kinetic data from allosteric and Michaelian enzymes. SigrafW uses a modified Fibonacci search to calculate maximal velocity (V), the Hill coefficient (n), and the enzyme-substrate apparent…

The intergenerational earnings regression in Canada suggest that credit limits educational choice. Nonlinearities in earnings regressions cannot be used as evidence of binding credit constraints, and concave regressions do not follow from credit constraints.

In this article, the authors describe a mixed-methods study designed to explore perceived family support, acculturation, and life satisfaction among 266 Mexican American adolescents. Specifically, the authors conducted a thematic analysis of open-ended responses to a question about life satisfaction to understand participants' perceptions of…

Modeling data behavior is differentiated from statistically determining a best-fit regression function, as it allows students to develop functions that hold certain attributes in respect to a set of data. Three techniques for developing polynomial models are demonstrated that afford students optional methods for determining appropriate polynomial…

No previous studies compare the prevalence of physiological hearing loss among older adults by nonmetro/metro residence. Also, there is little information on their relative successes in accommodating hearing loss with a hearing aid. This study sought to bridge these gaps by analyzing the 8,222 respondents to Wave 1 (1993?1994) of the national…

We consider the question of how variation in the number and reliability of indicators affects the power to reject the hypothesis that the regression coefficients are zero in latent linear regression analysis. We show that power remains constant as long as the coefficient of determination remains unchanged. Any increase in the number of indicators…

This article illustrates a method for fitting straight lines to data that is resistant to outliers and might therefore sometimes be preferred to the customary least squares procedure.

Purpose: This article examines factors that distinguish nursing facilities with very high and very low nursing assistant turnover rates from a middle referent group, exploring the possibility that high and low turnover are discrete phenomena with different antecedents. Design and Methods: Data from a stratified sample of facilities in eight…

This study is a quantitative analysis designed to compare two groups of factually innocent capital defendants: those who were exonerated and those who were executed. There are a total of 97 cases in the sample, including 81 exonerations and 16 executions. The primary objective of the authors is to identify factors that may predict case outcomes…

This article re-examines the question of what makes some grammatical structures more difficult to learn than others, arguing that this question can only be properly understood and investigated with reference to the distinction between implicit and explicit knowledge of a second language. Using a battery of tests that were designed to measure…