S5-1: Plan and conduct surveys and experiments using the statistical enquiry cycle: determining appropriate variables and measures; considering sources of variation; gathering and cleaning data; using multiple displays, and re-categorising data to find
This means that students will use the statistical enquiry cycle to plan and conduct investigations. The cycle has five phases that relate to each other. Some enquiries follow these phases in sequence but often new considerations mean that a statistician must go back to previous phases and rethink. The phases are:
- Summary, for example, what is the normal height of a 14-year-old female?
- Comparitive, for example, do males do more exercise than females?
- Relational, for example, is there a relationship between television watching and lack of exercise?
Students should analyse the data by comparing distributions visually using multiple graph types, preferably generated by technology. They should use informal inference to look for differences between distributions, for example, the median of one group is higher than the upper quartile of the other. Students should choose the most appropriate data display to report their findings and draw conclusions from the data related to their investigative question. They should recognise that all findings from the analysis of samples must be interpreted with uncertainty and be cautious in generalizing the results to whole.