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Age and video games Refer to Exercise 41. The study also estimated that 67% of adults aged 1829play video games, but only 25%of adults aged 65and older play video games.

a. Explain why you do not have enough information to give confidence intervals for these two age groups separately.

b. Do you think a 95% confidence interval for adults aged 1829 would have a larger or smaller margin of error than the estimate from Exercise 41? Explain your answer.

Short Answer

Expert verified

a. Sample sizes are unknown and sample proportions are given. It is not possible to give confidence levels.

b. It would have larger margin of error than estimate.

Step by step solution

01

Given Information

Sample size is decreasing and adults in sample is less than all individuals.

02

Why we do not have enough information to give confidence intervals for two age groups separately.

We should have knowledge of sample proportion and sample size to construct confidence interval. So, we do not have enough information to give confidence intervals for two age groups separately.

03

To check if 95% confidence interval for adults would have smaller or larger margin of error than estimate.

As number of adults are less than that in sample, we are decreasing sample size.

We have less information about population and less accurate estimates are obtained. Hence, estimate is far from true value and confidence interval has to be wider. Margin of error is larger as it is half of confidence interval.

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Most popular questions from this chapter

The researcher is deciding between a 95% confidence level and a 99% confidence level. Compared with a 95% confidence interval, a 99% confidence interval will be

a. narrower and would involve a larger risk of being incorrect.

b. wider and would involve a smaller risk of being incorrect.

c. narrower and would involve a smaller risk of being incorrect.

d. wider and would involve a larger risk of being incorrect.

e. wider and would have the same risk of being incorrect.

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a. Construct and interpret a 99%confidence interval for the proportion of all U.S. adults who think that organic produce is better for health than conventionally grown produce.

b. Does the interval from part (a) provide convincing evidence that a majority of all U.S. adults think that organic produce is better for health? Explain your answer.

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a. 0.0008

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