Sixty-one examiners provided a rating of whether a significant change in performance of handicapped individuals occurred across the baseline and treatment phases of six graphs of hypothetical data from single-subject designs. Results revealed considerable interrater disagreement on four graphs, especially those involving change in variability or…

The technique developed in this research paper for analyzing the information in charts and graphs is designed to reveal design flaws in the display that may prevent them from conveying information effectively. This analytic scheme requires isolating four types of constituents in a display and specifying their structure and interrelations at the…

The focus of this study was on the visual analysis of time series data for evaluating educational programs. Two characteristics of the data--changes in slope and variability--and two characteristics of evaluation--training in data utilization and the use of aimlines/decision rules--were manipulated. A total of 51 students and/or teachers in…