Identifying impediments to learning probability and statistics from an assessment of instructional software

A detailed multisite evaluation of instructional software designed to help students conceptualize introductory probability and statistics yielded patterns of error on several assessment items. Whereas two of the patterns appeared to be consistent with misconceptions associated with deterministic reasoning, other patterns indicated that prior knowledge may cause students to misinterpret certain concepts and displays. Misconceptions included interpreting the y-axis on a histogram as if it were a y-axis on a scatter plot and confusing the values a variable might take on by misinterpreting plots of normal probability distributions. These kinds of misconceptions are especially important to consider in light of the increased emphasis on computing and displays in statistics education.