Question

Q.1 Last month the NY Times published an article about an unusual of Iranian public opinion survey. They respondents were asked, "Are you willing to give up on the ability to produce nuclear weapons in the future for the full removal of economic sanctions?" They found that 40 percent of the respondents were willing. One of the factors that makes the survey unusual is that it was conducted by Israelis who telephoned 530 Iranian respondents in May and June. The random survey was conducted across Iran, the respondents were evenly divided between men and women, and the response rate was 27%.

1.Identify two possible sources of sampling error in this study and briefly describe why each could lead to sampling error. You'll be awarded one point for each correct source of error the associated description.
2.Identify two possible sources of non-sampling error in this study and briefly describe why each could lead to non-sampling error. You'll be awarded one point for each correct source of error the associated description.
3. Name the sampling method that they used to ensure that the respondents were equally divided between men and women. Briefly describe how they would have conducted this type of sample.

Answer 1

Possible sources of sampling error include non-response bias and sampling frame bias. Possible sources of non-sampling error include response bias and question wording bias. The researchers used stratified random sampling to ensure an equal division between men and women in the sample.

Step-by-step explanation:

1. Identifying possible sources of sampling error:

1. Non-response bias: This occurs when the individuals who choose not to respond to the survey have different characteristics or opinions compared to those who do respond. In this study, the low response rate of 27% could lead to non-response bias. The opinions and characteristics of the non-respondents may differ from those who participated, which can introduce bias into the results.
2. Sampling frame bias: This occurs when the sampling frame, or the list of individuals from which the sample is selected, is not representative of the target population. In this study, the use of telephone directories may not capture the entire population of Iranians, as some individuals may not have landlines or be listed in the directories.

2. Identifying possible sources of non-sampling error:

1. Response bias: This occurs when the respondents provide inaccurate or biased answers. In this study, the use of Israeli researchers conducting the survey may influence the respondents' willingness to answer truthfully. The respondents may be concerned about sharing their opinions with individuals from a potential adversary.
2. Question wording bias: This occurs when the wording of the survey questions influences the respondents' answers. In this study, the wording of the question itself could introduce bias, as it presents a trade-off between nuclear weapons and economic sanctions. The phrasing may influence the way respondents think about the issue and, subsequently, their willingness to give up nuclear weapons.

3. Sampling method used to ensure equal division between men and women:

The sampling method used in this study to ensure equal division between men and women is stratified random sampling. The researchers divided the population into two strata: men and women. They then randomly selected respondents from each stratum to ensure equal representation of both genders. This method helps to ensure that the sample accurately reflects the gender distribution of the population.