A survey of a random sample of U.S. adults by The pew Research Center for the People and the Press conducted in early January 2010 recorded each participant’s highest level of education completed and whether they knew that responding to the Census was required by law. Of the 973 participants who had some college or less, 271 knew that responding to the Census was required by law. Of the 526 participants who had a college degree or more, 195 knew that responding to the Census was required by law. Is there an association between a person’s level of education and her/his Census awareness?
a. Organize the data in an appropriate well-labeled 2 × 2 table.
b. Find the observed difference in the conditional proportion of those who knew that responding to the Census was required by law between those who had a college degree or more and those with some college or less.
c. Give two possible explanations for the observed difference in conditional proportions as reported in part (b).
d. Is this an experiment or an observational study? Explain how you are deciding.