Question 1
Selection bias can result from data samples
◦ that are not random.
◦ that compare groups engaged in different activities.
◦ from people who make different choices.
◦ All of these.
Question 2
Survivor bias
◦ is a type of selection bias.
◦ can only occur in studies involving people of significant age difference.
◦ is relatively insignificant with respect to economic research.
◦ All of these