Which of the following polls is most likely to have the most valid results?
A)A survey regarding presidential candidate preference conducted within a discussion group in which the participants already know each other (a church group, a group culled from the same office, etc.)
B)An online poll asking about presidential candidate preference
C)An exit poll conducted one-on-one with people who have just voted in a presidential election
D)A telephone survey about presidential candidate preference that is conducted at 6 p.m. each evening for one week

Question

Quizplus · Accepted Answer

A one-on-one exit poll about the candidate for whom a recent voter just cast their ballot is the poll that would have the most validity. The opinions of the participants are relevant to the poll's subject because they just voted. Voters are more likely to decline to participate in the poll than they are to lie about a subject as straightforward as choosing between two or three candidates. In any pre-voting poll, the participants must be "likely" or "intended" voters for the results to be reliable; assessing that quality is more difficult than determining whether or not someone walking out of a voting station just voted. Group responses are likely to be skewed by the involvement of multiple people, particularly when the respondents know each other personally. In online polls, especially those that are competitive, it is difficult to limit each voter to one vote or to assure the sample is diverse. Telephone surveys at 6 p.m. exclude people without phones, people who only have cellphones, and people who are working outside their home at that time of day (a disproportionately high number of blue collar workers).

Which of the Following Polls Is Most Likely to Have