Basic knowledge of ideas of causal inference can help students to think beyond data, that is, to think more clearly about the data generating process. Especially for (maybe big) observational data, qualitative assumptions are important for the conclusions drawn and interpretation of the quantitative results. Concepts of causal inference can also…

This article revisits how the end points of plotted line segments should be selected when graphing interactions involving a continuous target predictor variable. Under the standard approach, end points are chosen at ±1 or 2 standard deviations from the target predictor mean. However, when the target predictor and moderator are correlated or the…

The article serves as a guide for researchers in developing evidence of validity using bivariate correlations, specifically construct validity. The authors outline the steps for calculating and interpreting bivariate correlations. Additionally, they provide an illustrative example and discuss the implications.

Advances in validity theory and alacrity in validation practice have suffered because the term "validity" has been used to refer to two incompatible concerns: (1) the degree of support for specified interpretations of test scores (i.e. intended score meaning) and (2) the degree of support for specified applications (i.e. intended test…

We describe a semester-long project for an introductory statistics class that studies the broken windows theory of policing and the related issues of race, policing, and criminal justice. The most impactful feature of the project is the data-collection phase, in which students attend and observe a public arraignment court session. This "Court…

"Educational Research: Planning, Conducting, and Evaluating Quantitative and Qualitative Research" offers a truly balanced, inclusive, and integrated overview of the processes involved in educational research. This text first examines the general steps in the research process and then details the procedures for conducting specific types…

Every day, students collect, organize, and analyze data to make decisions. In this data-driven world, people need to assess how much trust they can place in summary statistics. The results of every survey and the safety of every drug that undergoes a clinical trial depend on the correct application of appropriate statistics. Recognizing the…

The learning sequence described in this article was developed to provide students with a demonstration of the development of box plots from authentic data as an illustration of the advantages gained from using multiple forms of data representation. The sequence follows an authentic process that starts with a problem to which data representations…

The National Early Literacy Panel (2008) report identified early predictors of reading achievement as good targets for instruction, and many of those skills are related to decoding. In this article, the authors suggest that the developmental trajectories of rapidly developing skills pose problems for traditional statistical analyses. Rapidly…

It is curious that so many people are accepting of statistics despite Disraeli's famous aphorism concerning "three kinds of lies." This acceptance certainly seems to hold for education statistics, especially when they imply something negative about American public schools. Sometimes people accept statistics because they are not in a position to…

Seven approaches to averaging reliability coefficients are presented. Each approach starts with a unique definition of the concept of "average," and no approach is more correct than the others. Six of the approaches are applicable to internal consistency coefficients. The seventh approach is specific to alternate-forms coefficients. Although the…

Multicollinearity is a well-known general problem, but it also seriously threatens valid interpretations in structural equation models. Illustrating this problem, J. Pietsch, R. Walker, and E. Chapman (2003) found paths leading to achievement were apparently much larger for self-efficacy (.55) than self-concept (-.05), suggesting--erroneously, as…

This paper presents findings from an historical investigation of visual literacy, a unique aspect being that the approach relied on the marriage of two disciplines--geography and history--which study change over time. Maps and their interpretation of data by cartographers tend to provide a foundational context that can illuminate past and present…

Describes two QuickBASIC programs that provide students direct experience with interpreting correlation scatter-plots. Maintains that the programs can be used in classroom exercises to highlight factors that influence the size of a Pearson correlation coefficient. (CFR)

Describes a QuickBASIC program for demonstrating the differences between main effects and interactions in factorial designs. The program can be used in conjunction with a traditional lecture to improve student understanding and develop skills in recognizing main effects and interactions from graphic displays. (CFR)