Sample, Random and Variation: The Vocabulary of Statistical Literacy

This paper considers the development of school students’ ability to define three terms that are fundamental to statistical literacy: sample, random, and variation. A total of 738 students in grades 3, 5, 7, and 9 were asked in a survey to define and give an example for the word “sample.” Of these, 379 students in grades 7 and 9 were also asked about the words “random” and “variation.” Responses were used to describe developmental levels overall and to document differences across grades on the understanding of these terms. Changes in performance were also monitored after lessons on chance and data, emphasizing variation for 335 students. After 2 years, 132 of these students and a further 209 students who were surveyed originally but did not take part in specialized lessons, were surveyed again. The difference after 2 years between the performance of students who experienced the specialized lessons and those who did not was considered, revealing no differences in performance longitudinally. For students in grades 7 and 9, the association of performance on the three terms was explored. Implications for mathematics and literacy educators are discussed.