Investigates 10th grade students' ability to handle data and interpretation by using a variety of tasks. Discusses the importance of developing student discussion as a route to better conceptual understanding of data presented in graphical form. (Contains 15 references.) (Author/YDS)

The present article presents a tutorial on how to estimate and interpret various effect sizes. The 5th edition of the Publication Manual of the American Psychological Association (2001) described the failure to report effect sizes as a "defect" (p. 5), and 23 journals have published author guidelines requiring effect size reporting. Although…

As a tour de force, data mining is likely to gain wider use in the next few years. To facilitate this transition, we make several recommendations addressed to both institutional research professionals and the Association of Institutional Research.

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…

Schools today are more data rich than ever, requiring staff members to develop their data literacy--that is, their knowledge of how to use assessment data with other types of data to identify areas of effectiveness and to target instructional improvement efforts. Administrators and teachers are expected to use combinations of data (diagnostic and…

Organizing the work of instructional improvement around a process that has specific, manageable steps helps educators build confidence and skill in using data. A process that includes eight distinct steps can take school leaders to use their assessment data effectively, and organized these steps into three phases: Prepare, Inquire, and Act. The…

The academy schools programme in England is presented by Government as the means by which increased diversity and private participation in the provision of public education can be used to solve educational and wider social problems. The entrepreneurial features of academy schools are examined, through a study of the sponsors and the ethos, values…

This paper analyses technology-based instruction on data-analysis with box plots. Examples of instruction taken from the research literature inform a study of two classes of 17 year-old students (upper secondary) in which the mathematical relationships that their teachers targeted are distinguished as being, or not being, relevant to statistical…

The role of curriculum-based data in educational decision making, particularly with regard to the assistive technology (AT) consideration process, has become increasingly important. The No Child Left Behind Act of 2001 (NCLB) and other demands for school accountability require teachers to be more thoughtful about all decisions regarding students…

Describes an activity that (1) illustrates the classical experiment as a research tool; (2) demonstrates the interplay among hypotheses, methods, and data; and (3) nurtures the excitement of a method of study. (BSR)

Examines national Current Population Survey data to indicate the impact of sample size on the standard error of subpopulations in the sample and to show how these errors can influence policy conclusions. Examines the unemployment rate cross-sectionally for 11 states to demonstrate that the monthly unemployment rate should not be used to make fine…

Test validity refers to the degree to which the inferences based on test scores are meaningful, useful, and appropriate. Thus, test validity is a characteristic of a test when it is administered to a particular population. This article introduces the modern concepts of validity advanced by S. Messick (1989, 1996, 1996). Traditionally, the means of…

Calculated power for 6,155 statistical tests in 221 journal articles published in 1982 volumes of "Journal of Abnormal Psychology,""Journal of Consulting and Clinical Psychology," and "Journal of Personality and Social Psychology." Power to detect small, medium, and large effects was .17, .57, and .83, respectively. Concluded that power of…

Examines the comparability of various types of income inequality data used in cross-national research. Focuses on more stringent definition and measurement of income. Presents income distribution data (quintile distributions and Gini coefficients) for 61 nations that meet these stricter requirements. Contains 37 references. (SV)

Meta-analysis synthesizes related research by considering three major factors: sample size, magnitude of significance, and statistical test used. These factors produce an effect size, expressed as a correlation or as a difference between means, divided by the standard deviation. Discusses ways to use effect size when results are not consistent and…