Statistical Literacy: From Idiosyncratic to Critical Thinking

This paper follows earlier research using a survey instrument devised to measure statistical literacy understanding at the school level. Based on partial credit Rasch analysis, the performance of 673 students in Grades 5 to 10 is reported both overall and for three subgroups of items reflecting strands within statistical understanding. The three strands are the basic measurement of average and chance, the related ideas of sampling and inference, and the representation of data and variation. A hierarchy of six levels of understanding is presented, with differing trends across the grades discussed and an example of individual student performance at each level given. Some of these examples illustrate student differences in understanding for the different strands. Implications for the school curriculum are considered with respect to potential development across the years of schooling and realistic expectations for students at various grade levels. Issues for further consideration and research are raised in the final section.