Question

Prior to the mayoral election discussed in Exercise 33, the newspaper also conducted a poll. The paper surveyed a random sample of registered voters stratified by political party, age, sex, and area of residence. This poll predicted that Amabo would win the election with 52% of the vote. The newspaper was wrong: Amabo lost, getting only 46% of the vote. Do you think the newspaper’s faulty prediction is more likely to be a result of bias or sampling error?

Answer 1

Sampling error arises when the estimated statistic does not provide the true of the population under study. The bias is one of the reasons that sampling error occurs while conducting the study. The other reason of sampling error is that the sample does not gets selected on random basis.

It is given that the paper surveyed a random sample of registered voters stratified by political party, age, sex, and area of residence and predicted that Amabo would win the election with 52% of the vote. But the prediction appeared to be wrong as Amabo got only 46% of the vote, so he lost the election by 6% of the vote. The faulty prediction of the newspaper is more likely to be the result of sampling error as the sample selected by newspaper is based on convenience of the researcher which does not represent the exact mood of the registered voters. The other reason might be the stratification done on the basis of political party, age, sex, and area of residence is not done properly.

Therefore, the correct answer is sampling error.