In a survey on corporate ethics, a poll split a sample at random, asking

533

faculty and corporate recruiters the question: "Generally speaking, do you believe that MBAs are more or less aware of ethical issues in business today than five yearsago?" The other half were asked: "Generally speaking, do you believe that MBAs are less or more aware of ethical issues in business today than five years ago?" These may seem like the same question, but sometimes the order of the choices matters. In response to the first question,

56%

thought MBA graduates were more aware of ethical issues, but when the question was phrased differently, this proportion dropped to

43%.

Complete parts a through c.

a) What kind of bias may be present here?

A.

Nonresponse bias

B.

Response bias

C.

Voluntary response bias

b) Each group consisted of

533

respondents. If we combine them, considering the overall group to be one larger random sample, what is a

99%

confidence interval for the proportion of the faculty and corporate recruiters that believe MBAs are more aware of ethical issues today?

%,%

(Round to one decimal place as needed.)

c) How does the margin of error based on this pooled sample compare with the margins of error from the separate groups? Why?

A.

The margin of error based on the pooled sample is larger since the sample size is larger.

B.

The margin of error based on the pooled sample is smaller since the sample size is larger.

C.

The margin of error based on the pooled sample falls between the margins of error for the separate groups since its sample proportion is the mean of the two separate groups' sample proportions.