Variability and comparing data sets stand in the heart of statistics theory and practice. "Variation is the reason why people have had to develop sophisticated statistical methods to filter out any messages in data from the surrounding noise" (Wild & Pfannkuch, 1999, p. 236). Concepts and judgments involved in comparing groups have been found to be a productive vehicle for motivating learners to reason statistically and are critical for building the intuitive foundation for inferential reasoning (Watson & Moritz, 1999; Konold and Higgins, 2003). Thus, both variation and comparing groups deserve attention from the statistics education community.<br><br>The focus in this paper is on the emergence of beginners' reasoning about variation in a comparing groups situation during their encounters with Exploratory Data Analysis (EDA) curriculum in a technological environment. The current study is offered as a contribution to understanding the process of constructing meanings and appreciation for variability within a distribution and between distributions and the mechanisms involved therein. It concentrates on the qualitative analysis of the ways by which two seventh grade students started to develop views (and tools to support them) of variability in comparing groups using various numerical, tabular and graphical statistical representations. In the light of the analysis, a description of what it may mean to begin reasoning about variability in comparing distributions is proposed, and implications are drawn.
The CAUSE Research Group is supported in part by a member initiative grant from the American Statistical Association’s Section on Statistics and Data Science Education