A city planner is studying two characteristics of households:
• D : “the household owns at least one dog”
• N : “the household subscribes to a printed daily newspaper.”
a. (i) Explain clearly what it means to say that the events D and N are independent.
b. (ii) Give two plausible real-world reasons why the assumption of independence between D and N might fail.
c. (iii) Describe, in words only, how survey data collected from a random sample of households could be used to test whether D and N are independent.