Question

Administrators at a school are interested in whether or not the location of a student's locker impacts how often they visit the locker during the school day. They decide to randomly select fifteen occupied lockers from each floor (for a total of ninety lockers) and interview the students who use those lockers. Explain why this does not meet the criteria for a simple random sample.

a) It does meet the criteria for a simple random sample.
b) It introduces selection bias based on locker locations.
c) It ensures a diverse and representative sample.
d) It guarantees accurate results.

Answer 1

The sampling method used by the school administrators introduces selection bias based on locker location and does not provide an equal chance for all occupied lockers to be selected, thus not meeting the criteria for a simple random sample.

Step-by-step explanation:

The selection method used by the administrators at the school does not meet the criteria for a simple random sample. The criteria for such a sample require that each individual has an equal chance of being chosen at any stage of the sampling process. In this case, because lockers are randomly selected from different floors rather than from the entire group of all occupied lockers without considering location, the method introduces a selection bias based on locker location. Each student's locker has a different probability of being chosen depending on which floor it is on, rather than all students having the same chance irrespective of their locker location.

Therefore, the correct answer is: b) It introduces selection bias based on locker locations.