A researcher took a random sample of 64 individuals across the country to investigate the relation between hours worked per week and income earned per year. For each individual, the hours worked per week and yearly income (measured in ‘000’s dollars) were recorded. In addition to the variables of hours worked and income earned, the individuals were also asked to respond to survey questions concerning other variables (e.g. location, age, etc).
First, the researcher categorised the data into six location groups and six age groups and calculated the frequencies as presented in the tables below