Konold et al. (2002)

We interviewed 7 and 9 grade students to explore how they summarized and reasoned about data. The students were near the end of an eight-week collaborative research project in which they analyzed data they had collected on the types and frequencies of animals killed on town roads. During our interviews, students worked with data similar to those they had collected to answer questions we posed about conditions that might affect the number of animals struck by cars. To summarize their data, students tended to use a "modal clump", a range of data in the heart of a distribution of values. These clumps appear to allow students to express simultaneously what is average and how variable the data are. Modal clumps may provide useful beginning points for explorations of more formal statistical ideas of center.