Collecting and Describing Data
How data is gathered without bias, and how it is summarised honestly.
01Data CollectionPopulations and samples, the main sampling methods and how to compute a stratified or systematic sample, the sources of bias, types of data, and the principles of good questionnaire and experiment design.100 questions02Describing DataMean, median and mode; range, interquartile range, variance and standard deviation; stem-and-leaf diagrams and box plots; identifying outliers and describing skewness; and the effect of coding on the mean and standard deviation.100 questions