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Television stations sometimes solicit feedback volunteered by viewers about a televised event. Following a televised debate between Barack Obama and Mitt Romney in the 2012 presidential election campaign, a TV station conducted a telephone poll to determine the "winner." Callers were given two phone numbers, one for Obama and the other for Romney, to register their opinions automatically. (a) Comment on whether or not this was a random sample. (b) How might this poll have been improved?

Short Answer

Expert verified
Part a) No, this was not a random sample as people who responded voluntarily might not represent the entire demographic watching the debate. Part b) The poll could have been improved by implementing a system for random selection of respondents, for instance by randomly selecting phone numbers or email addresses from their subscriber database and assuring respondents of their anonymity to reduce bias.

Step by step solution

01

Analysing the sampling method

From the information given, we understand that the TV station allowed viewers to actively phone-in and register their opinions using different numbers for Obama and Romney, which is a form of voluntary response sample. This sample is not a random sample because every individual in the population does not have a known, non-zero chance of being selected. Only the viewers who felt strongly about the event probably called, thus the sample is not representative of the entire population's opinion.
02

Suggesting improvement in polling method

To improve this poll, the sample selection process could be changed to better represent the entire population. The best method would be to use a simple random sampling procedure, where every person or viewer has an equal chance of being selected. This might involve randomly selecting viewers' telephone numbers, or randomly emailing a certain number of viewers and asking them to answer. Also, ensuring anonymity would reduce bias and improve response rates.

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Key Concepts

These are the key concepts you need to understand to accurately answer the question.

Voluntary Response Sample
A voluntary response sample is a type of sampling method where participants choose to participate in the survey on their own, rather than being randomly selected by the researcher. This method can be quick and easy to implement because it does not require selecting or contacting participants individually. However, it often results in a sample that is not representative of the entire population.

The reason why this sampling method tends to be flawed is that it can attract participants who have strong opinions, leading to a bias in the results. For instance, in our exercise, people who felt intensely about the televised debate might have been more inclined to call in. This doesn't necessarily reflect the broader, more neutral views of the entire population.

Overall, while voluntary response samples can be useful for quick feedback, they should be used with caution. The results can be heavily skewed due to a lack of random selection, leading to conclusions that aren't entirely accurate.
Random Sampling
Random sampling is a method used to ensure that each member of a population has an equal chance of being chosen for the sample. This approach is highly valued in research because it significantly reduces bias and improves the representativeness of the sample.

In random sampling, you might gather a full list of the population and use a random number generator to select participants. By doing so, you help ensure that the sample reflects the diverse opinions and traits present in the whole group, not just those of individuals who choose to participate of their own accord.

For the TV station poll, switching to a random sampling method would mean every viewer would have had an equal chance of being contacted to provide their opinion on the debate. This would likely have yielded more reliable results, providing a more accurate measure of public opinion.
Non-representative Sample
When a sample is non-representative, it does not accurately reflect the characteristics of the larger population it is meant to represent. This often occurs in voluntary response samples and other non-random sampling methods, resulting in biased outcomes.

In the context of our exercise, the TV station's use of telephone numbers for voting might have attracted participants who were already motivated to express their views. As a result, the responses collected were likely unrepresentative of the general population. For example, those without strong feelings may have not bothered to call, skewing the results.

Ensuring a representative sample involves selecting participants in a way that mirrors the broader population. This can help to produce data that more closely aligns with the true opinions and traits of the entire group.
Bias in Surveys
Bias in surveys is a concern that researchers aim to minimize because it can significantly distort the results. Bias can enter a survey in multiple ways, including through the sampling method, question phrasing, and survey administration.

A major source of bias is the sampling process, as observed in voluntary response surveys. When participants choose to respond on their own, those with strong opinions might overshadow others, leading to biased findings.

In the TV station poll scenario, bias likely arose from the self-selection of participants, who were emotionally invested in the debate outcome. To mitigate such bias, using random sampling would provide every individual an equal chance to share their opinion, smoothing out any extreme perspectives and leading to a more accurate reflection of the population's views.

Ultimately, minimizing bias in surveys involves careful consideration of how participants are selected and how questions are framed. By doing so, researchers can ensure that survey results are as objective and informative as possible.

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Most popular questions from this chapter

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