Typical longitudinal growth models assume constant functional growth over time. However, there are often conditions where trajectories may not be constant over time. For example, trajectories of psychological behaviors may vary based on a participant's age, or conversely, participants may experience an intervention that causes trajectories to…

The present guide provides a practical guide to conducting latent profile analysis (LPA) in the Mplus software system. This guide is intended for researchers familiar with some latent variable modeling but not LPA specifically. A general procedure for conducting LPA is provided in six steps: (a) data inspection, (b) iterative evaluation of models,…

The multilevel social relations model (SRM) is a commonly used statistical method for the analysis of social networks. In this article and accompanying supplemental materials, we demonstrate the estimation and interpretation of the SRM using Stat-JR software. Multiple software templates permit the analysis of different response types, including…

Data collected in many biology laboratory classes are on ratio or interval scales where the size interval between adjacent units on the scale is constant, which is a critical requirement for analysis with parametric statistics such as t-tests or analysis of variance. In other cases, such as ratings of disease or behavior, data are collected on…

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…

Describes the way a relational database management system manages a large historical data collection project. Shows that such databases are practical to construct. States that the programing tasks involved are not for beginners, but the rewards of having data organized are worthwhile. (GG)

This study explored some practical issues for single-case researchers who rely on visual analysis of graphed data, but who also may consider supplemental use of promising statistical analysis techniques. The study sought to answer three major questions: (a) What is a typical range of effect sizes from these analytic techniques for data from…

Since the first edition of "Schools and Data", the No Child Left Behind Act has swept the country, and data-based decision making is no longer an option for educators. Today's educational climate makes it imperative for all schools to collect data and use statistical analysis to help create clear goals and recognize strategies for…

A live demonstration of how a typical set of educational data can be examined using quantitative statistical software was conducted. The topic of tutorial support was chosen. Setting up a hypothetical research scenario, the researcher created 300 cases from random data generation adjusted to correct obvious error. Each case represented a student…

This document is the users' guide for Version 1.0 of the Public-Use data tapes compiled by the National Assessment of Educational Progress (NAEP), 1985-86. The Public-Use tapes are produced to allow outside researchers access to the NAEP data. The tapes accompanying this guide, one for grade 3/age 9, one for grade 7/age 13, and one for grade…

Educators' fear of statistics stems from various factors, including deficiencies in their preparation programs: insufficient relevance, inadequately integrated technologies, and stress on inferential statistics. Attendance statistics are worthless unless principals and superintendents can interpret them and incorporate them into their…