Focusing on structural features of a scenario: An activity on expected frequencies, deviations, and chi-square contributions

Abstract

In this paper, I present a way to teach statistics by helping students reuse structural features of a problem to interpret those features. It consists of explaining concepts by presenting corresponding analogical examples following a given story. Expected frequencies, deviations and chi-square contributions are presented in relation to a story where six people found tokens on a geocaching course. The activity prepares students to gradually interpret these three elements of the chi-square statistic test on their own. The activity also allows for a discussion about benefits of the chi-square test of independence, namely its added value compared to proportions that can show spurious results