Use of the arithmetic mean: An investigation of four properties issues and preliminary results

Our investigation utilised Strauss and Bichler's conceptual organisation of the properties of the mean, and had three purposes: (1) to investigate what happens developmentally to those statistical properties that were not mastered by age 12-14; (2) to examine the qualities of the statistical properties, including their relative conceptual difficulty and their relative ability to evoke the concept of the mean; and (3) to determine the relative effectiveness of different testing formats in assessing subjects' knowledge about the component properties of the mean.