Thirty students wrote a statistics examination having a maximum of 50 marks. Refer to the previous question. The following is a stem-plot of the birth weights of male babies born to the smoking group. The stems are in units of kg. Refer to the previous question.
Pie charts are better than bar graphs for comparing relative sizes.
Data that are nominal scale are presented using frequency tables. Means and standard deviation of ordinal data are meaningless. The scatter-plot is the basic graphic tool for investigating relationships between two interval or ratio scaled variables. Box-plots are a good choice for comparing the distribution of values among groups. The scatterplot is the basic graphical tool for investigating relationships between two continuous interval or ratio scaled variables.