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On September 25, 2011 Michael Vick, the quarterback for the Philadelphia Eagles broke his non-throwing hand in a football game against the New York Giants. ESPN then posted a poll on their website.

The poll asked viewers to predict which team would win the NFC East Division. The Eagles play in the NFC East Division. By 4:15 pm, 914 fans had voted. 25% of them thought the Eagles would still win the division.


What can we conclude from a 95% confidence interval about the opinions of ESPN viewers?


A. We are 95% confident that between about 22% and 28% of fans thought the Eagles would still win the division

B. nothing because the count of successes is too small

C. nothing because the sample was not randomly selected

D. We are 95% confident that between about 22% and 28% of ESPN Viewers thought the Eagles would still win the division.

User SeanA
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Final answer:

The ESPN poll indicated that 25% of a sample of 914 fans believed the Philadelphia Eagles would still win their division. Without actual z-score calculations for the 95% confidence interval, we can't select a correct answer with certainty, but possible sample bias suggests that conclusions might not be representative of the entire population of viewers.

Step-by-step explanation:

Based on the poll conducted by ESPN, where 25% of 914 fans thought the Philadelphia Eagles would win the NFC East Division after Michael Vick's injury, we can calculate a confidence interval to estimate the opinion of all ESPN viewers. To calculate a 95% confidence interval, we need the point estimate, which is the sample proportion (p), and the error bound. The point estimate is 0.25 since 25% of the sample group believes the Eagles will win. Assuming a normal distribution, the error bound (E) for a 95% confidence interval is typically calculated using a z-score for the desired level of confidence and the sample proportion.

The formula for the error margin in a proportion is: E = z * sqrt((p * (1 - p)) / n), where z is the z-score corresponding to the 95% confidence level, p is the sample proportion, and n is the sample size. However, without the actual computation it is impossible to verify which confidence interval, from the provided options, is correct. Therefore, without further calculations, the most reasonable choice would be to conclude nothing since the chosen answer should be driven by these calculations.

It is important to note that the sampled opinions may not be representative of the entire population, especially because the sample was not randomly selected. This could introduce bias, as only interested viewers who happened to visit the ESPN website at the time of the poll would have participated.

User Gassa
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