Use the Following Information for Following Questions

Multiple Choice

Use the following information for following questions:. A researcher wonders whether speed of
service at a diner is affected by whether a male customer is wearing a suit jacket. The researcher used the
following study design to collect data: The researcher chose five diners in a large city and recorded the
number of male customers who wore a suit jacket during a two week period. He also records how long it
took a waiter or waitress to address the customer. He finds that male customers who wear suit jackets
were addressed by the wait staff faster than male customers who did not wear a suit jacket.
-Choose the statement that correctly explains why we can or cannot generalize these results to a larger population.

A) This was an observational study so results can be generalized to a larger population.
B) The male customers (and diners) were not selected from a larger population, so the results cannot be generalized beyond the sample.
C) The male customers were randomly selected to participate in the study so the results can be generalized to the larger population.
D) The male customers were randomly assigned to wear a suit jacket so the results cannot be generalized to beyond the sample.