Measures of central tendency (English subtitles available)

The programme uses a story of the training of a basketball team to introduce the measures of central tendency. In appointing a team captain, they consider the averages of the heights of the team members. The heights are used as a set of ungrouped data for calculating the averages which include the mean, the median and the mode. These three averages are the measures of the central tendency of their heights. The programme uses various daily-life experiences such as the mean cost of a meal, the median of salaries and the mode of shoe sizes to illustrate the calculation of mean, median and mode. It focuses on the understanding and interpretation of statistical information. Pupils are led to explore the effect of the central tendency of a set of the data when adding a common constant to the whole set of data; or multiplying the whole set of data by a common constant. The programme brings forth a common example of a set of grouped data collected from an ordinary survey. As an extension of the content of another ETV programme on “Statistical Diagrams & Graphs”, this programme further introduces the constructions of frequency distribution table, cumulative frequency distribution table and cumulative frequency curve. The calculation of mean, median and mode of a set of grouped data is then elaborated. Finally, the programme encourages the enquiry on the characteristics, appropriateness and effectiveness of the uses of different averages in different situations.
Please click here for the Chinese version.