Question

In 2010, National Public Radio (NPR) conducted a survey of preferences and habits of its Facebook fans by recruiting respondents through messages posted on its Facebook page. The survey was conducted online and deployed July 12-19. A total of 40,043 respondents began the survey, with 33, 304 completing all questions. It was found that people accessed NPR on the radio, at NPR.org, through iPhone apps, and several other platforms. Asked about time spent with NPR, about 20% of respondents indicated that they spent more than three hours per day, including radio listening, (a) This is what NPR says about the survey methodology: "Respondents were self-selected and the resulting sample is non-random -- therefore a margin of error cannot be calculated, and the survey results cannot be projected to any population other than the sample itself." Why can't inference about any population be made? The sample randomly selected. (b) Suppose that people who spent more time with NPR were more likely to respond to the survey. Do you think the true percentage of NPR's Facebook fans who spend more than three hours with NPR is higher or lower than the 20% found from the survey? Explain why, Select the best explanation for your response to this question. The true percentage is most likely higher. People who don't often spend time with NPR probably don't visit the NPR Facebook page. The true percentage is most likely higher. People who don't often spend time with NPR probably don't visit the NPR Facebook page. The true percentage is most likely lower People who don't often spend time with NPR probably don't visit the NPR Facebook page. The true percentage is most likely lower. People who don't often spend time with NPR are probably not on Facebook

only B

Answer 1

a)

Sample is not randomly selected as it was mentioned in the above survey methodology that sampling is non-random, so there would be some biasedness in the data due which we can't estimate the population.

b)

Option (C) would be the most suitable options amongst all.

Reason- Refer the q's again and look at it what the respondants say about the NPR survey, that is why it is most likely to be lower, because they didn't visit the facebook page.

NOTE- As only B is asked that is why, i have done this else i wanted to confirm that answer you have selected in the image B is correct.