TESTING

Hypothesis testing is one of the key concepts in statistics, yet it is also one of the least understood concepts. The purpose of this study was to investigate teachers’ understandings of early forms of hypothesis testing in an effort to generate insights into ways of supporting their design of effective strategies for teaching hypothesis testing. To this end, we conducted a professional development seminar and interviews with 8 high school statistics teachers in 2001 in the southeast US in which we attempted to unpack the difficulties and conceptual obstacles teachers encountered as they thought about methods by which they could test the validity of a claim made about a population that is based on a single sample. We found that teachers ’ difficulties in such situations were rooted in their non-stochastic conceptions of probability and in their lack of understanding of the logic of indirect argument. We conclude by offering promising pedagogical approaches for developing teachers ' understandings of data-based inference. Liu & Thompson Proto-hypothesis Testin