In a large city school system with 20 elementary schools, the school board is considering the adoption of a new policy that would require elementary students to pass a test in order to be promoted to the next grade. The PTA wants to find out whether parents agree with this plan.
a) If they put a big ad in the newspaper asking people to log their opinions on the PTA Web site what kind of bias might they encounter?
A. response bias due to desire to give acceptable answers
B. nonresponse bias
C. bias due to the use of a voluntary response sample
D. bias due to a poor sampling frame resulting in undercoverage
E. no bias
