Suppose that there are two (2) candidates (i.e., Jones and Johns) in the upcoming presidential election. Sara notes that she has discussed the presidential election candidates with 21 friends, and 14 said that they are voting for candidate Jones. Sara is therefore convinced that candidate Jones will win the election because Jones gets more than 50% of votes.
Answer the following questions in the space provided below:
- Based on what you now know about statistical inference and using a one-tail alpha (0.025), is Sara’s conclusion a logical conclusion? Why or why not?
- Compute the 95% confidence interval?
- What role does the margin of error play in determining how many individuals should be sampled if we desired a margin of error plus or minus .000001?
- How would you explain your conclusion to Sara without using any statistical jargon? In other words, is her original sample size sufficient or should she interview more people to obtain an accurate prediction.
- What inference test should she use?
- Based on the result obtained:
- What z-score did she obtain?
- What should her conclusion state?