The manager of a local cell phone company wants to conduct a survey to determine what kind of musical ring tones people typically use. Which method should she choose – and why?
A. survey the listeners of a rock radio station
B. survey a group of people standing in line
for a symphony
C. Suppose she decides to mail a survey to every 100th household in the area.
Kathy wants to know how many students in her city use the internet for learning purposes. She used an email poll. Based on the replies to her poll, she found that 83% of those surveyed used the internet.
Is this Biased or unbiased? Why?